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Human Biology – Notes
Please note: these are not all the notes from the semester. You are responsible for any
articles, handouts and textbook work that we did in class. You are also responsible for all
diagrams that we did – look at your quests to help you out.
The Human Body . . . Facts
1. In what part of the human body are more than half the bones located? Hands and Feet
2. What is the fastest recorded ‘sneeze speed?’ 165 km/h
3. About how many times does the average heart beat in a lifetime? 3 billion
4. A full-grown adult has 206 bones. How many does a newborn have? 350
5. Which organ in your body is liquid? blood
6. True or False? Everyone is color blind at birth? true
7. True or False? The surface area of your small intestine is about the same size as a tennis court? true
8. True or False? Food will get to your stomach, even if you are standing on your head. True
9. What is the largest organ in the human body? skin
10. How many cells are there in the average adult? 100 trillion
11. How many bones in the skull and upper jaw? 21
12. True or False? There are no bones in/around your throat? False (hyoid)
13. About what fraction or % of the body’s mass is muscle? 50%
14. True or False? Muscles push on bones to produce movement. False
Abiotic or Biotic
Abiotic – this includes all objects that are not alive and have never been alive.
Biotic – this includes all organisms that are living AND that were once living (i.e. dead ones are included)
What Makes Something living?
1. Made of Cells
2. Obtain and use energy (food)
3. Grow and develop
4. Respond (reaction) to their environment (when plants/grass dry up when it is very hot for long periods of time – trying to
conserve water)
5. Reproduce
6. Adapt to their environment (rabbits changing color for winter/spring for protection; squirrels collecting nuts for the winter)
*An object must show ALL of the above characteristics in order to be considered ‘living’
Activity:
For each of the following, decide if it is:
a) living
b) non-living, but was once part of a living thing
c) non-living and was never part of a living thing
 silk – b
 leather – b
 steel knife – c
 rubber – b
 beans – a/b
 cotton – a/b
 water – c
 sugar – b
 block of wood – b
 sand – c
Unit I: Nutrition
What is Nutrition?
Nutrition is the study of different kinds of nutrients and how your body uses them.
What are Nutrients?
Nutrients are the chemicals in food that your body needs to supply your cells with energy.
There are 6 kids of Nutrients in food
Nutrient
How it is used
Sources
Carbohydrates
Provides the major source of fuels for the human
body.
Bread, pasta, cereals, rice …
Fat (lipids)
Reserve energy – stored as an extra energy source.
Nuts and seeds, oils, butter, cream, meat, milk
Protein
Makes body tissues such as blood and bone. Also
used for growth and repair.
Nuts, meat (pork, chicken, beef, fish), seeds and beans,
some veggies, milk, eggs, tofu, soy
Vitamins
Needed to release energy. Help growth, fight
diseases, maintain proper functions of the body.
Minerals
Help muscles work correctly and for proper
growth
Fruits (Vitamin C)
Carrots (Vitamin K)
Sunlight (Vitamin D) etc…
Calcium (milk and supplements)
Sodium/Chlorine (salt)
Potassium (bananas)
Water, food (watermelon, tomatoes, cucumber)
Water
Our bodies are ~60% water. It cools the body and
helps remove waste.
What is a Balanced Diet?
A balanced diet has the right amount of each nutrient.
Recommended Daily Allowance
The amount of each vitamin and mineral a person needs to stay in good health. Sometimes listed as IU (international units) or
in milligrams.
Average percentage of each nutrient in Males and Females
Nutrient
Male
Female
Carbohydrates
2%
2%
Fat
18%
30%
Protein
20%
18%
Water
60%
50%
What is a Calorie anyway?
A calorie is the energy contained in what we eat and drink. It is the amount of energy required to raise the temperature of one
gram of water by one degree celcius.
What is the recommended Caloric intake?
Women = 1940 calories a day
Men = 2550 calories a day
The amount of exercise you do, and your size, affect the number of calories you should have in your diet because the body burns
calories at a faster rate when you workout.
Nutrient
Total Fat
Saturated fat
Cholesterol
Sodium
Potassium
Carbohydrate
Fibre
Protein
Daily Values
65 g
20 g
300 mg
2400 mg
3500 mg
300 g
25 g
50 g
Table values based on a 2000 calorie diet; for
adults and children over 4 years old
Saturated Fats – fat that is found in foods from animal meats and skin, dairy products and some vegetables.
Cholesterol – a type of lipid (fat) found in food from animal sources. This means that eggs, meats, and whole dairy products
(including milk, cheese, and ice cream) are loaded with cholesterol – vegetables, fruits, and grains contain none.
Potassium – type of nutrient found in a variety of food from bananas, apples, broccoli and peas.
Fibre – The part of plant foods that the body cannot digest. It helps to move food waste out of the body more quickly. Fibre is found in
fruits, vegetables, dry beans and peas, nuts and seeds, and breads and cereals.
Unit II: The Cell and Digestion *All diagrams can be enlarged for a better look
The Cell
Organelle
Mitochondria
Appearance
Function
-powerhouse
-produces tons of energy needed for cell activities
Endoplasmic
Reticulum
- moves fluids/chemicals through cytoplasm
- smooth or rough (ribosomes – contain nucleic acids needed for protein sysnthesis
Golgi
Apparatus
-produces/accepts lipids/enzymes and packages them for export (to be used by cell)
Lysosome
-digest large molecules
-can destroy cell if membrane is broken and contents escape
Vacuole
Nucleus
Bubble like
- contain water and help maintain water balance
- may contain wastes or food
- directs cell activity
- stores genetic material (center = nucleolus)
Cell
membrane
- boundary for the cell
- controls passage of materials in and out of the cell
Cytoplasm
- supplies cell needs
- removes wastes
Centrioles
-organization of spindles which attach to chromosomes during cell division (needed
for reproduction)
Microvilli
- increase cell surface area for more efficient absorption of materials into the cell
Cilia
-help move particles along the surface of the cell
Pinocytes
-help with moving larger particles across the cell membrane
Digestion: The breaking down of food molecules into small enough pieces to be absorbed by cells. Digestion takes place in the
digestive tract, a long curvy tube (more than 9 m long) which includes the mouth, esophagus, stomach, small intestine and large
intestine.
Digestive System: The group of organs involved in the digestion process plus the ‘helper’ organs and glands (ex: liver, pancreas, bile
duct)
Two Types of Digestion
1) Mechanical digestion (physical): food is broken down into smaller pieces by chewing, grinding etc
2) Chemical digestion: food changes form by reacting with acids and enzymes in the digestive tract
The Digestion Process
1) Step One: The MOUTH
a. Teeth and Tongue
b. Salivary glands and Saliva
c. Enzymes
d. Swallowing and the Epiglottis
A. Teeth: Necessary for initial breakdown of food. Teeth vary in size and shape; each has different roles. Humans usually get 2 sets of
teeth: primary (starting at ~6 months) and permanent (6-13 years, with wisdom teeth coming in around high school). Most adults have
32 teeth: 8 incisors, 4 canines, 8 premolars, and 12 molars
 Incisors: front of the mouth (4 top and 4 bottom), they are chisel shaped and are good for biting/cutting
 Canines (eye teeth): on either side of the incisors, more pointed in shape, they are for tearing and shredding food
 Premolars/molars: located at the side of the mouth behind the canines, square shaped, flattened on upper surface, for
grinding and chewing
Crown: the visible part of the tooth; the part above the gums
Enamel: the hardest substance in the body. It can’t be replaced
naturally if it gets chipped or worn away. Loss of enamel
exposes the dentine (bone-like material that forms most of the
tooth) which is sensitive to touch, temperature, acids, and
sugar
Root: is held in place by tissues which connect the tooth to the
jawbone
Tongue: acts as a taste organ and it also mixes
saliva with food and moves it toward the rear of
the mouth for swallowing
B. Salivary Glands: under the tongue by the lower jaw, they start to produce saliva when we sense or think about food. Saliva: needed
to help moisten food so that it’s easy to swallow
C. Enzymes: are chemicals found in saliva that helps to speed up digestion, they start to break down some of the carbohydrates in food
even before it leaves the mouth
D. Swallowing: moves the chewed up food into the throat (5 inches long), this is accomplished by muscle movements in the tongue
and mouth. Epiglottis: located in the throat behind the tongue, but in front of the larynx. The epiglottis closes off the windpipe while
opening the esophagus when we swallow.
2) Step Two: THE STOMACH
a. Esophagus and Pharynx
b. Cardiac Sphincter and Stomach
A) Esophagus:
 The esophagus is about 25 cm long and leads from the pharynx (part of the neck and throat) to the stomach
 The wall is made up of several layers
o Inside: thin lining covered in mucus (helps food move down easier)
o Second Layer: contains glands that produce the mucus
o External portion – two layers of muscles
 One layer is arranged in a circular fashion and passes around the esophagus
 The other layer is longitudinal, running the length of the tube
 Finally there is a thin sheet of tissue around the outside, which helps keep the esophagus in place

The food is squeezed along the digestive tract by wavelike movements of muscles/muscle contractions called peristalsis
o It works only in one direction, except when we are ill
B) Sphincter: at the end of the esophagus, a muscular ring called the sphincter lets food go into the stomach and then squeezes shut to
keep food/fluid from going back into the esophagus.
Stomach: stomach muscles churn and mix with acids/enzymes, breaking the food into a thick liquid called chyme
 When chyme is a the right consistency to pass into the small intestine, it does that in order to continue the digestion process,
so that the body can absorb the nutrients into the bloodstream
 Some things like water, salt, sugar and alcohol can be absorbed (used) directly through the stomach wall
3) Step Three: The INTESTINES
a) Small intestine
b) Large intestine and rectum

Most food we eat needs further digestion after the stomach, so it travels to the intestines where it’s turned into a form we can
absorb.
A) Small Intestine: it is about 7 m long and most digestion happens here. It’s coiled up inside the body cavity so that it can be that
long. There are three parts:
o Duodenum (25-30cm): bile and pancreatic juices are added to the chime to further digestion
o Jejunum (100-110 cm): maximum absorption of digested food minerals and water takes place here – it is deep red
because of all the blood vessels.
o Ileum (150-160 cm): specifically responsible for absorbing vitamin B12 and the re-absorption of bile salts.
B) Large Intestine (bowel): about 1.5 m long, but greater in diameter than the small intestine. This is where food that didn’t get
digested (fibre) is prepared for elimination.
o The large intestine reabsorbs water and maintains the fluid balance of the body
o It absorbs certain vitamins
Rectum: the last part of the large intestine and digestive tract. This is where all the non-digested food ends up before being expelled by
the anus.
Absorption: the movement of food from the digestive system to the blood.
 The inner wall of the small intestine is lined with 1000s of tiny bumps called villi
 Digested food surrounds each villus; the food leaves the small intestine through 2 types of tubes
o Capillaries, which carry blood (absorb all nutrients except fats)
o Lacteals, which carry a liquid called lymph (absorb digested fats)
o Although they are separate initially, lymph eventually empties into the blood stream (near the heart); thus the blood,
which circulates through the entire body, carries all the nutrients
Unit III: Excretion
Excretion vs. Elimination ppt
• Your body makes several kinds of waste, which fall into two groups:
– Undigested solid wastes
– Wastes made by cells
Elimination
• Undigested solid waste leaves your body through the large intestine
– Water is removed from the wastes in the large intestine, which allows for the formation of a solid (feces).
–
–
The solid wastes moves from the large intestine to the rectum.
From the rectum, the solid waste is excreted through the anus.
Excretion
• When waste products made by cells (water, heat, carbon dioxide, salts, urea) leave your body
• In many animals, CO2 leaves the body through the lungs
• The liquid waste, urine, is made in the kidneys
• Urine: made up of water, heat, harmful chemicals (urea), and some salts
• Perspiration: when heat, water, and salt are excreted by the body through skin (i.e. sweating)
The waste products are:
Skin = water, heat, salt
Large Intestine = solid waste
Lungs = carbon dioxide
Kidneys = harmful chemicals, heat, salt
The Excretory System
• The group of organs responsible for removing waste products from the body = the excretory system
• The main organs are:
– Lungs
– Kidneys
– Skin
Lungs
• When we breathe, we excrete CO2 waste, and small amounts of heat and water
• Fact: your lungs are capable of removing alcohol from the blood; this is how a breathalyzer is able to determine a person’s
blood alcohol level
Skin
• Largest organ; excretes most of the body’s waste heat
• Also removes some water, salts, and very small amounts of urea
• Perspiration: helps the body ‘cool off’
– When sweat evaporates from the skin, it cools the body, removing heat
Kidneys
• Fist sized, bean shaped (i.e. kidney bean) organs found on either side of the lower spine
• Main job is to filter out wastes from the blood, making them more concentrated in preparation for excretion and, in the
process of doing this, retaining as much water as possible
• The blood enters the kidney through the renal arteries; renal veins carry blood back from the kidneys to the body
•
A ureter connects each kidney to the urinary bladder; once urine has formed, the ureter carries the urine (produced after the
blood has been filtered for wastes) from the kidney to the bladder
•
•
Another tube, the urethra, carries the urine out of the body
In males, the urethra passes through the penis; in females, it lies between the pubic bone and the front wall of the vagina
Nephrons
• The filtration of the blood takes place in minute structures called nephrons, found in the cortex, which is the outer layer of the
kidney
• The nephrons estimate at more than 1 million per kidney
• In spite of their size, the kidneys filter more than 180 L of blood every 24 hours
– Most is reclaimed by the body, only 1.5 L of urine is passed each day
– Your blood passes through the kidneys 300 times per day
Liver
• A secondary organ of excretion
• Does not excrete wastes, but is important for excretion
• Handles cell wastes in several ways:
1) Breaks down dead red blood cells: pass into digestive tract, then eliminated with solid waste by the bowels
2) Weakens certain harmful substances
3) Changes some harmful substances
Ex: the liver makes bile from harmful substances – bile is important in fat digestion – after bile works on fat, it is
eliminated from the bowels
4) Combines certain harmful chemicals
Ex) liver combines ammonia and some CO2 – forms urea, which the blood carries to the kidneys where it becomes
part of the urine
Disorders Affecting the Excretory System
Urinary Tract Infections:
 Most common problems treated by doctors
 Caused by bacteria invading the kidneys, bladder or urinary tract
 Examples of infections include cystitis (sis-ti-tis), bladder infection, kidney infection and nephritis
 Common symptoms for urinary infections include pain or burning sensation during urination and a sense of needing to pass
urine frequently, although the volume passed may be small; urine may be cloudy, foul smelling or bloody; symptoms many
be accompanied by fever, chills, lower back pain ***it is possible to have an infection with no symptoms at all
 Doctors usually prescribe antibiotics or medication to reduce pain
Kidney Stones
 Sometimes some of the salts found in the urine form small crystals that are hard and insoluble called kidney stones
 They can form almost anywhere in the urinary tract, but are usually found in the kidneys
 When they are painful and obstruct the flow of urine they may have to be surgically removed
 Ultrasound is also used to shatter the stones so that the pieces may be passed with urine
 Using flexible fibre optics – a tube is passed up through the urethra or through a small hole in the kidney; optic fibres allow
the surgeon to see into the kidney and locate the stones, which can then be removed by suction
Note: Urine
 In addition to the wastes that we would expect to find in urine, some usable substances are present as well. Physicians use the
analysis of urine samples as a common diagnostic technique. The presence or absence of a particular substance in the urine
may direct the physicians attention to a problem or provide information about the malfunction of a particular organ
o Drug testing
o Pregnancy tests
Unit IV: Integumentary (Skin)
Important Vocabulary
 Skin – outer covering of the body
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Sebaceous gland – a gland that secretes an oily substance
Capillary – the smallest type of blood vessel with a wall once cell thick through which oxygen can pass
Vein – a blood vessel carrying blood to the heart from other tissues – deoxygenated blood
Artery – a blood vessel carrying blood from the heart to other tissues
Melanin – a brownish-black pigment that is found in the skin and the hair
Erector muscle – the tiny muscle that contracts to pull hair upright or erect
Keratin – a tough protein of hair, nails and other outgrowths of the skin
Capillary network – connecting system of capillaries branching to reach many cells, bringing food and oxygen to the skin
Skin: Epidermis and Dermis
Epidermis
• The epidermis is the outer layer of our skin
• It is made of several layers:
1. Stratum corneum
2. Stratum lucidum
3. Stratum granulosum
4. Stratum germinativum
Stratum corneum
• The stratum corneum is the layer we touch and care for; it is only dead cells
• This layer contains NO blood vessels (i.e. nutrients can’t be brought to the epidermis)
• When the cells die, they undergo a chemical process that changes them from soft, easily damaged cells into ones that are
harder and tougher.
•
Keratin is a protein that helps harden these cells and makes them waterproof, thereby helping to prevent water loss by the
body
• Although dead, these cells can pass on sensations such as pressure to the nerve endings in the layers below the epidermis
Stratum Germinativum
 The stratum germinativum (jer-min-a-tiv-um) is the bottom layer of cells in the epidermis, which is made up of cells which
divide to produce new cells (cell division)
• As new cells are produced, they push older cells above them toward the surface of the skin.
• The outer layer is constantly shedding dead cells
• The SG layer of the epidermis produces the pigment melanin which gives skin color, and allows the skin to tan
• Melanin production is stimulated by exposure to ultraviolet light; doses of sunlight cause the skin to tan
• Prolonged exposure to the sun may destroy several layers of epidermal cells and cause sunburn/blisters
• Freckles are caused by uneven distribution of melanin (small irregular patches)
Dermis
• Underneath the epidermis
• Contains living tissues which are specialized to monitor the changes that occur in the environment immediately around the
body
• Contain collagen fibres: limits how much the skin can be stretched
•
Contains elastic fibres: pulls the skin back after stretching
•
Contains blood vessels: for regulating body temperature in response to impulses from special heat/cold receptors
– There are also touch, pressure, and pain receptors; found within different levels of the dermis
– Contains many dermal papillae: blood in these dome-shaped structures nourish the germinative layer above
Between the Dermis and Epidermis
• Where the epidermis and the dermis meet, there is a wavelike layer formed of many tiny cones and ridges
• These patterns show through the surface of the skin on the hands and feet, some of them becoming fingerprints
• The patterns emerge while the baby is developing in the uterus and never change, except with respect to size
• Patterns on the skin of fingers can be classified into 10 basic arrangements of loops and whorls
• Even identical twins will have some differences (even if they are not obvious from facial feature, body size etc)
Nails, Moles, Warts, Skin Cancer, Birthmarks, and Wrinkles
Nails
• Nails are made of keratin (like hair!)
• Nails grow under the cuticle at the nail base.
• Extra keratin is added to the nail in the nail matrix.
• Nails grow 0.5mm each week. Fingernails grow faster than toe nails.
Common Nail Problems
• Ingrown Nail: when the nail curves down and into the skin, causing pain, and sometimes infection
• Nail Injury: when you drop something on your nail a bruise may appear under it; the nail may fall off, but a new one will
grow
• Nail Deformity: when the nail isn’t smooth on the surface.
• Hangnail: when a loose strip of dead skin hangs from the edge of a fingernail
Moles
• A mole is a flat or raised mark that varies in shape, colour and texture.
• It is the overproduction of skin pigment cells (melanocytes).
• Most people have between 10 – 20.
• Moles may become malignant and pose health risks. They should be seen by a doctor.
Warts
• Warts are a small growth caused by a viral infection of the Human Papilloma Virus (HPV)
• Causes the overgrowth of epidermal cells.
• Excess cells are pushed upward and cause a lump. Planters warts, on people’s feet, are flat and can cause pain.
Skin Cancer
• Basal Cell Carcinoma: fast dividing cells in the base of the epidermis are damaged by UV exposure and begin multiplying
out of control. Stays in epidermis.
• Malignant Melanoma: radiation damage to pigment-producing cells. A dark mass forms and some cells break into the
dermis and travel in the blood to other locations.
Birthmarks
• unusual patters of capillaries (red)
• heavily pigmented or bumpy layers of skin
• some disappear and some can be removed
• most are harmless
Wrinkles
• small folds in the skin that occurs as skin ages
• skin loses elasticity and does not snap back into place
• long exposure to sun and wind can cause wrinkles to occur quickly
Interesting Facts
• Your skin weighs between 2.5-3.5 kg (about 10 lbs)
• You have the same number of hair follicles as a chimpanzee
• Men and women have about the same number of hair, but female is finer
Senses in the Skin
• There are several different types of sensory nerve endings in the skin
• These endings are called receptors because they are the parts of the nervous system from which information is received
• The receptors are named according to their function
Touch Receptors (Meissner’s corpuscles)
• Located immediately below the epidermis
• Most numerous in the tongue and fingers
• They are stimulated by light pressure on the skin
• Allow a person to distinguish between rough, smooth, hard and soft
• A different touch receptor detects hair movement
Pressure Receptors (Pacinian corpuscle)
• Located beneath the dermis
• Stimulated by heavy pressure
Pain Receptors (Nociceptor)
• Located in the epidermis and dermis
• Evenly distributed throughout the skin
• They occur almost everywhere throughout the body except the brain
– This is why we can be awake during brain surgery and still feel sensation, but no pain
Temperature Receptors (thermoreceptors)
• There are separate hot and cold receptors
• They are stimulated by sudden changes in temperature
Sweat Glands
• Adults have over 2 million sweat glands
• There are two types:
1. The first kind is found everywhere on the body except on the lips. They produce a watery solution of salt and urea
which evaporates from the skin and cools the body
2. The second kind is found under the arms and in the groin area. They produce a thicker liquid. The bacteria on your
skin feed off this and produce substances that stink!
Unit V – The Skeletal System
Interesting Facts
 Babies have 350 bones
 An adult skeleton has 206 bones
 Girls who drink excessive amounts of colas, coffee, or other caffeine drinks are at greater risk of developing osteoporosis
(bone disease)
 Bone is not dead – it is constantly growing, changing, and developing; it is supplied with blood vessels and nerves
 You (students) do not yet have an adult skeleton. It won’t be complete until you at 25 years old
 There are 3 bones in each inner ear that transmit sound waves from your ear drum
 Over have your bones are in your hands and feet
Endo/Exo skeletons
 Humans, and other vertebrates have an internal skeleton called an endoskeleton
o The human skeleton is mostly made up of bone. It also has some softer tissues called cartilage (ears and tip of nose
are good examples)
 Some organisms, like crabs/insects, have an outer skeleton called an exoskeleton
Bone Formation and Parts of a bone
 The formation of bones starts when a fetus is ~2 mo. It develops bone cells called osteocytes. Once started, the process of
ossification (bone formation) occurs throughout life, although the major part occurs in the first 20 years.
 There are Four Main types of bone
o Flat: like those found in the skull; provide protection for soft tissues and points for muscle attachment
o Long: found in the arms and legs; provide strength and support
o Short: found in the wrists and ankles; not much longer than they are wide; provide flexibility
o Irregular: i.e. backbone, middle ear; have shapes related to a specialized function (ex: vertebra have small extensions
for muscle attachments and an opening for the spinal cord)

Parts of a Bone
o Periosteum: the layer that covers a bone; it is the membrane that controls the development of bone
o Two Tissues:
 Compact bone – the hardest part of the bone
 Spongy bone – lighter, full of tiny holes; contains many more blood vessels
o Bone Marrow: the center of bones; responsible for making red/white blood cells
Bone
Humerus
Upper or
Lower
Limb
Upper
Fibula
Metacarpals
Tibia
Radius
Clavicle
Patella
Tarsals
Femur
Carpals
Phalanges
Metatarsals
Ulna
Lower
Upper
Lower
Upper
Upper
Lower
Lower
Lower
Upper
Both
Lower
Upper
Common Name/Description
The bone of the upper arm; connects the scapula at the shoulder with the 2 bones of the lower arm at
the elbow
The other bone in the lower leg; provides stability (behind tibia)
Bones of the hand (palm)
Shin bone: larger of the 2 bones in the lower leg, connects with the femur
Beside the ulna; slightly shorter bone, which rotates around the ulna so that the hand can be turned
Collar bone: connects at one end of the sternum and at the other end with the scapula
Kneecap: flat, disc-shaped bone; protects the joint where the femur and tibia are connected
Ankle bones
Thigh bone; longest and strongest bone in the body
The small bones that make up the wrist
Fingers and toes
Larger bones of the foot (instep)
Main supporting bone of the forearm; attached to the humerus at one end and the bones of the wrist at
the other end
Organization of the Human Skeleton
Your skeleton is made up of two parts; the axial skeleton and the appendicular skeleton.
Axial: Forms the central axis of the body
Skull (including tiny bones in ears)
Vertebral column
Ribs (12 pairs)
Sternum
Sacrum
Coccyx
29
24
24
1
1
1
Total
80
Appendicular: makes body movement possible and protects the organs of digestion, excretion, and reproduction. The word
appendicular refers to anything attached to a major part of the body
Pectoral girdles (2x2)
4
Arms (3x2)
6
Wrists (8x2)
16
Hands (19x2)
38
Pelvis
2
Legs (4x2)
8
Ankles (7x2)
14
Feet (19x2)
38
Total
126
The adult skeleton has a total of 206 bones.
Functions of the Skeleton
 Supports the body (framework)
 Protects delicate internal organs and various parts of the body i.e. skull protects the brain / ribs protect the lungs
 Stores calcium
 Produces new red and white blood cells:
o Blood cell production: Bones have tube-like canals. They are filled with soft tissue called marrow. Red blood cells
and some white cells are made in bone marrow
 Helps with movement; provides areas of attachment for muscles
o Movement: some joints are moveable, some are not Ex) joints in skull are not moveable, but joints in hands, legs,
feet, arms are moveable. Most joints are held together by ligaments (tough connective tissues that hold bones
together at moveable joints) which stretch easily. This allows the bones to move easily. Bones and muscles work
together to produce movement.
Joints: A joint is a point in the skeleton where bones meet
Types of Joints
1. Immovable: bones fit tightly together (skull)
2. Hinge: permit back and forth movement (elbow, knee)
3. Ball and socket: allow movement in all directions (hip, shoulder)
4. Pivot: allow side to side, as well as up and down movement (base of skull)
5. Gliding: allow some bending and twisting movements (wrists, between each vertebra)
The Vertebral Column
 The spine
 Made up of 26 irregularly shaped bones
 Each vertebra has one round drum shaped body with 3 wing-like projections
 The vertebrae are held together by bands of ligaments
 There is a hole in the middle of each vertebra for the spinal cord
 The way our spine is made, it limits how much we can bend forward/backward
o Some people are more flexible than others
The Pelvis
 Resembles a bowl-shaped dish without a bottom
 Provides attachment for the bones of the lower limbs
 Extremely strong and bears most of the weight of the body, as well as the force of all leg movements (ex. Running, walking,
jumping…)
 Women have a wider and lighter pelvis than males, and the opening is significantly larger in females so that they can give
birth
The Sternum and Ribs
 12 pairs of ribs that are flat, curved bone
 First 7 pairs are attached by cartilage to the sternum (breast bone)
 Next 3 pairs lie below the sternum; each pair is attached by cartilage to the pair of ribs above
 The last 2 pairs are called floating ribs because they do not complete the circle and are not attached in front (these ribs are
easily broken)
The Lower Limbs
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Femur: longest and strongest bone; its round, smooth head fits into a socket formed in the pelvis
Patella: flat, disc-shaped bone just in front of the joint for protection. Loosely attached to allow movement
Tarsal bones: 7 of these bones make up the ankle; these provide a sliding joint which allows the foot to be extended and
flexed
The Upper Limbs
 Scapula: is loosely held in place by ligaments and muscles, so the arm has great freedom of movement in almost any
direction
 Wrist: is made up of 8 small bones (carpals) which are joined to the 5 metacarpals that form the hand
o The bones that make the fingers and thumb are called phalanges (there are 3 in each finger and 2 in each thumb)
Unit VI: Muscular System
Interesting Facts
 Muscle cells cannot partially contract. They act on the ‘all or none’ principle. They either contract 100% or do not contract at
all.
 When you are cold, your muscles produce rapid contractions to generate body heat (shivering).
 A cramp is a painful muscle contraction.
 Tetanus is a very severe type of contraction. It is a persistent contraction that can be caused by a bacterial infection.
Sometimes you get a ‘tetanus shot’ to prevent this. Tetanus can cause lockjaw.
 A spasm is rapid involuntary contraction of a muscle. You may have had one in your eye before - tick.
 You cannot turn fat into muscle by exercising.
 You cannot ‘spot reduce’ i.e. you cannot get rid of your spare tire by doing sit-ups.
Movement
 You are always moving. Even when you are sleeping, your muscles are working. Movement only stops when life stops.
 Movement within cells is caused by chemical reactions. All other body movements are caused by muscles.
 You have more than 600 muscles.
 Muscles make up 40% of your body mass.
 Muscles work by contracting. When a muscle contracts it shortens. Without your muscles, your bones could not move. When
a muscle contracts it pulls on a bone, producing movement. Muscles can only pull bone; they cannot push bones.
Types of Muscles
 Not all our muscles are used for locomotion. Some allow us to wink, swallow etc. There are three main types of muscles. At
the cellular level they all have the same function – to contract. When we move beyond the cellular level we see differences in
their functions:
Type 1: Skeletal Muscle
 Muscles that move your arms and legs
 These are the ones that you control – they move when you want them to
 They are attached to bone
 Often called voluntary muscles
 Under a microscope they look striped or striated so they are called striated muscles
Type 2: Smooth Muscle
 Often called involuntary muscles because you cannot control them
 These muscles form the wall of most of the digestive tract; they are also found in blood vessels and other internal organs
 Under a microscope they look smooth
Type 3: Cardiac Muscle
 This is the heart muscle
 Under a microscope, cardiac muscle appears striated like voluntary muscles BUT cardiac muscle is involuntary – you have
no control over your cardiac muscle
Muscle Attachment
 For one bone to move toward another bone, a muscle is needed. This muscle will have 2 points of attachment
1. Origin: The place at which a muscle is attached to the stationary (not moving) bone
2. Insertion: The place at which a muscle is attached to the movable bone
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Muscles are attached to bones by tendons.
Tendons are tough, inelastic bands of connective tissue – they are very strong
A tendon is the thickness of a pencil and can support a load of several thousand kilos
As the tendons are small, they can pass in groups over a joint or attach to very small areas for the muscle itself to find room
for attachment
 Although they are very tough, they are subject to wear and tear as they rub across bone surface
 Tendons may become inflamed (tendonitis) when athletes work out in cold weather without adequate warm clothing, or
without doing warm ups
Antagonistic Muscle Pairs
 Many muscles act in pairs
 This is necessary since a muscle can only pull by contracting
 When a bone moves, movement in the opposite direct can occur only if there is another muscle that can pull the bone in that
direction
 These muscles are called antagonistic pairs
Exercise
 There are two types of exercise:
 Type 1: Isotonic Exercise
 Results in movement
 Ex) running, lifting weights etc
 Type 2: Isometric
 Muscles are pitted against each other
 This is exercise that does NOT result in movement
 Ex) Pushing a wall; hooking fingers together and trying to pull hands apart
 Such exercises have been shown to increase strength and muscle size rapidly
Movement in Joints
1. Abduction: movement away from the side of the trunk or midline of the body Ex) raising arms to the side; swinging leg to the
side
2. Adduction: movement toward the trunk or midline (opposite of abduction)
3. Flexion: bending or bringing bones together Ex) bending elbow or knee
4. Extension: straightening Ex) straightening elbow or knee
5. Dorsal flexion: moving the foot towards the tibia (shin)
6. Plantar flexion: moving the foot away from the tibia. Ex) standing on your toes
7. Pronation: twisting the forearm by turning palm face down (when hand is held out front)
8. Supination: twisting the forearm by turning palm face up (when hand it held out front)
9.
Horizontal adduction: movement of humerus from side-horizontal to front-horizontal Ex) pushing a barbell during a bench
press
10. Horizontal abduction: movement of humerus from front-horizontal to side-horizontal Ex) rowing a boat
11. Elevation: movement upward Ex) shrugging the shoulders
12. Depression: movement downward
*These diagrams are not exactly like the one I gave you – these are only guides, use the diagram from the class
Unit VII: Circulation
• Circulation, or transportation of blood is a vital function; life can’t go on without it
• The Circulatory System is made up of:
– The heart
– The blood vessels
– The blood
Blood
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•
•
•
Physical Characteristics: red, sticky, distinctive taste/smell, dries quickly
Sometimes called ‘life stream’ – it flows through our bodies carrying necessities of life (oxygen, nutrients, chemical
messengers) to the cells, as well as transporting away the wastes produced by the cells (carbon dioxide, heat, extra water)
It only takes your blood 30 seconds to circulate through your entire body
The average human body contains about 5 litres of blood:
– 55% is made up of plasma (straw coloured fluid which is 90% water and carries many dissolved substances)
– 45% is solids (red and white blood cells, and platelets)
Red Blood Cells
• Called erythrocytes
• Produced in bone marrow
• Round with a hollow depression in each side
• It’s shape gives it a large surface area, while remaining small, allowing it to pass through very tiny blood vessels
• No nucleus
– An unusual characteristic for cells; they start off having one, but as the cells mature their nucleus shrinks and
disintegrates
• Oxygen carriers of the body
• Contain haemoglobin which is a compound containing iron
• The haemoglobin molecule can combine with four oxygen molecules creating the bright red compound called
oxyhaemoglobin
– It releases oxygen when your body needs it
• Red blood cells are responsible for a lot of work, so they wear out quickly – they only last 3-4 months
• Old red blood cells are broken down in the liver and spleen and the iron in them is returned to the bone marrow for new cells
to use
– The replacement rate is 1-2 million cells per second
White Blood Cells
• Called leukocytes
• Contain a nucleus
• Colorless, and although are usually spherical they can change shape
• Larger than red blood cells, but are far less numerous
• There is 1 white blood cell for every 600 red blood cells
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Most are produced in bone marrow, but some are also produced in lymph tissue at several sites in the body
Several types of white blood cells
Function – to protect the body from infection and disease-causing organisms (pathogens)
All white blood cells possess the following characteristics which help them perform their function:
• Amoeboid Action: can move independently; can change shape and squeeze through tiny pores to move into and out
of body tissue
– Phagocytes – can surround bacteria and digest their toxic proteins; can join together in order to surround large
products which must be removed from the body
– Chemical Properties – react to charged particles, proteins and other chemicals which may be present in areas of
injury and inflammation; some cells produce chemicals called antibodies (proteins) to neutralize the effects of
certain foreign chemicals
Platelets
• Much smaller than red blood cells – about 250 000 to 300 000 for each mm3
• Responsible for the initial stages of blood clotting, the process which prevents loss of blood from a wound. If blood doesn’t
clot, you would loose too much blood and die.
• No nucleus; not actual cells, but are tiny fragments of cells that contain a special enzyme that initiates clotting
Blood Types
• Determined by the presence or absence of certain antigens on the red blood cells
• Two types of antigens: A and B
• If A is present, type A blood; if B is present, type B blood; if both present, type AB; if neither are present, type O blood
• The antibodies found in blood are always the opposite of their antigen (blood type)
• For example, type A blood contains the A antigen, but the B antibody (needed to fight off foreign antigens . . .things other
than A
Type of Blood
Antigens Present on
Red Blood Cells
Antibodies Present in
Blood Plasma
A
A
B
B
B
A
AB
A and B
Neither A or B
O
Neither A or B
A and B
Rh factor
• This is an antigen (chemical) found on the red blood cells of most people
• If your blood has the chemical your blood is said to be Rh positive (Rh +)
• If your blood does not have it, your are Rh negative (Rh -)
• Connected to your blood type
• Ex) your blood may be AB+
• It is particularly important for expectant mothers to know their blood’s Rh factor – if it is the opposite to the baby’s this could
be a big problem and the baby’s life could be in danger since the mother’s blood may attack the baby’s
Moving Blood throughout the Body
• Blood flows through your body through a closed system of tubes called blood vessels
• Your body has three main types of blood vessels:
– Arteries
– Veins
– Capillaries
• Arteries
– Carry blood away from the heart
– Blood is rich in oxygen and nutrients
– Cary the materials needed by the cells
– Arterioles = small arteries
• Veins
– Carry blood from the body back to the heart
– Blood in the veins carries dissolved waste material
– Venules = smaller veins
• Capillaries
– Tiny and thin tubes that connect arterioles and venules
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Most of the blood vessels in your body are capillaries
The Heart
• Blood is pumped throughout your body by the heart
• The heart is located in the thoratic cavity, well-protected by the rib cage
• The heart is nestled between the lungs, with its lower end slightly toward the left side
• An adult heart is about the size of a large fist (300 g)
• It is not rigidly attached to any of the surrounding tissues, but is suspended by the large blood vessels attached to it
• This allows it to move loosely in place as it contracts
Parts of the Heart
• The heart muscle has two separate pumps
• Right side: responsible for collecting blood from the body and pumping it to the lungs
• Blood flows back from the head and arms to this side of the heart through a large vein called the superior vena cava, which
leads into the upper right-hand chamber called the right atrium
• Blood from the trunk and legs enters the same chamber via the inferior vena cava
• Both the right and left atria are thin-walled chambers which lie above the ventricles – their function is to collect blood and to
pass it to the ventricles (contracting vessels)
• Right ventricle – connected to the right atrium via the tricuspid valve, which prevents blood from flowing back into the
atrium when the ventricle contracts
• When the right ventricle contracts, it pushes blood into the pulmonary artery, which carries blood into the lungs where its
load of CO2 wastes are released and a fresh load of oxygen is absorbed
• The newly oxygenated blood flows into the left atrium through the four pulmonary veins – this portion of the circulatory
system (the heart to lungs and back) is called pulmonary circulation
• Contractions of the left atrium push the blood through the bicuspid valve into the left ventricle (largest and most heavily
muscled chamber of the heart), which forces blood to every part of the body as it contracts
• The blood is pushed out from the left ventricle to the largest blood vessel in the body, the aorta – this portion of the
circulatory system is called the systemic system since it supplies blood to the remaining body systems
Blood Pressure
• If the blood is to reach the hands and feet, the brain, and every part of the body, it must be pumped out of the heart under very
considerable pressure
• Highest pressure occurs in the aorta
• As blood passes into smaller vessels and the distance from the heart becomes greater, the pressure decreases
• The pressure in any vessel varies as a result of 5 major factors:
• The amount of blood – if there is loss of blood, the pressure in the system drops because of the decrease in volume
• The heart rate – the faster the heart pumps blood, the greater the pressure which is built up (there is more blood);
pressure falls as the heart rate decreases, especially during sleep/rest
• The size of the arteries – when arteries dilate (larger in diameter), the volume of the vessels increases and the
pressure falls (more room to flow). If the arteries constrict pressure is built up because of the extra resistance to
blood flow
• Elasticity – the walls of arteries must be flexible and elastic in order to expand as blood is forced out of the heart,
and then relax after the blood has flowed through. If they can’t stretch properly they are ‘hardened.’ This is common
in older people and results in high blood pressure
• The viscosity of blood – viscosity = thickness of blood; thick, sticky fluids flow less readily than thin, watery fluids
Measuring Blood Pressure
• Normal blood pressure is less than or equal to 120/80 mm Hg
• Systolic Pressure: numerator; the highest pressure generated when the ventricles contract
• Diastolic Pressure: denominator; when the ventricles relax and the elastic walls of the arteries offer the least resistance
Unit VIII: Genetics
Genetics is the study of heredity. It looks at understanding the biological properties that are transmitted from parent to offspring.
DNA (deoxyribonucleic acid) is the chemical structure of the chromosome. Within DNA is the genetic code.
 DNA is used by (almost) all living organisms. (some use RNA)
 There are 4 parts to DNA called nucleotides: A (adenine), T (thymine), C (cytosine) & G (guanine).
 A long sequence of these letters makes a gene.
 Our entire DNA is very long (would stretch over a metre), and so it is divided into chromosomes.
 Each cell in our bodies has exactly the same DNA, but only certain genes are “turned on” at a time.
 Ex: The genes that determine our hair colour are only “turned on” in our hair follicle cells. The genes that determine our
height are turned on in our bone and muscle cells.
A gene is a portion of the DNA responsible for a certain trait or characteristic.
 Ex: body part structure, hormones, proteins, eye color, hair color etc.
Chromosomes are small, rod shaped bodies in the nucleus that contain hereditary genetic material. Humans have 23 pairs of
chromosomes, 46 in total – 23 from our mother and 23 from our father.
Here’s how DNA is wound into chromosomes
Dominant and Recessive Traits
• Some genes are dominant and others are recessive.
• A dominant trait will ‘mask’ the recessive trait and will be the one expressed.
• A recessive trait is not expressed, though the person still ‘carries’ that trait.
• B = brown eyes (dominant) – we always use a capital letter for the dominant gene
• b = blue eyes (recessive) – we always use the small letter of the dominant gene for the recessive
ex) curly hair = dominant = C
straight hair = recessive = c
• If a person receives a brown eyed gene from her mother and a blue eyed gene from her father, she will be Bb, and she will
have brown eyes. She can still pass on blue eyes to her child though.
Genotypes are the combination of genes inherited from both parents which are responsible for a certain trait.
– A brown eyed person could be Bb or BB
– A blue eyed person would be bb
The phenotype is the visible expression of genes. Ex) The person has blue eyes or the person has brown eyes.
Homozygous – if both alleles (individual genes) are the same (BB or bb)
Heterozygous – if the alleles are different (Bb)
Some traits are controlled by a single gene:
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Tongue Rolling
Widow's Peak
Wet ear wax
L/R interlocking finger
Attached earlobes
Hitchhiker Thumb (r)
Chin fissure
Darwin tubercle
Dimples
Long eyelashes
Short big toe
Except for the Hitchhiker thumb, all of these genes are dominant.
Punnett’s Square – used to determine the probability of a child having a certain trait.
• Punnett’s squares allow us to cross the genes of the mother and father to determine the possible genotypes of the offspring.
• A Punnett’s square takes the alleles from each parent and examines the outcomes.
• If a heterozygous father with brown eyes and a heterozygous mother with brown eyes have a baby, could their child have
blue eyes? Draw the Punnett’s square, list the genotypes and the phenotypes.
Phenotypes:
____% will have brown eyes
____% will have blue eyes
Genotypes:
____% homozygous dominant
____% heterozygous dominant
____% homozygous recessive
Practice Punnett’s square: A homozygous man with attached earlobes (EE) and a heterozygous woman with attached earlobes (Ee) have a
baby. Fill in the Punnett’s square and list the phenotypes and genotypes.
Phenotypes:
Genotypes:
Complete the following questions using Punnett’s squares. List the phenotypes and genotypes for each.
1.
2.
3.
Both of your parents have dimples, which are dominant. They both have heterozygous genes.
Your mother has hitchhikers thumb which is recessive, you father doesn’t, but he carries the allele for it.
Your father has a homozygous widow’s peak, which is dominant. Your mother does not have one.
Unit IX: Respiration
The need for oxygen
Humans need oxygen to survive (250 mL/min). We can live several days without water, weeks without food, but only minutes
without oxygen
Composition of atmosphere: 78% nitrogen, 21% oxygen, 0.03% carbon dioxide
Cells obtain energy by breaking down sugars; oxygen is needed for this to happen
The process of breaking down sugars into energy is called cellular respiration:
C6H12O6 + 6O2 → 6H2O + 6CO2 + energy
The opposite is photosynthesis
Nasal/oral cavity
Air enters through the nasal cavities or the mouth. Three important things happen:
 Foreign particles are prevented from entering because of tiny hairs.
 Air is warmed and moistened as it enters the body.
Pharynx
From the nasal cavity, air travels through the pharynx (air filled channel in the mouth) into the larynx through the epiglottis.
Your tonsils are located in the pharynx
Epiglottis
The pharynx also opens into the esophagus where food travels to the stomach.
When food is chewed, it is forced to the top of the mouth, and pushed backwards. This forces the epiglottis to close, allowing
food to enter the esophagus, not the trachea.
If you swallow too fast, cilia (hair-like protein structures) push particles out of respiratory tract and force a violent cough.
Larynx
Air travels through the larynx, commonly called the voice box.
Elastic ligaments create sound when air from the lungs is forced towards the pharynx.
The larynx is protected by a thick band of cartilage, commonly called the Adam’s Apple. The growth of this cartilage and larynx
during puberty cause the deep voices of males.
Trachea -> bronchi -> bronchioles
Air travels through the trachea (12 cm longs) and through right and left bronchi. These structures contain cartilaginous rings for
support.
The bronchi lead to the right and left lung, leading air into the bronchioles.
Alveoli
The bronchioles lead to the alveoli.
The alveoli are surrounded by capillaries. It is here where oxygen and carbon dioxide exchange takes place.
The Lungs
Well protected by the ribs, sternum and spine
Contained within the pleura, 2 membranous sacs which surround the lungs
The pleura help to isolate each lung
For air to enter the lungs, 2 basic actions must occur:
1. The diaphragm – a thin, dome shaped sheet of muscle (~level with the bottom of the ribs), is curved upward in the middle,
like an upside down saucer – as we breathe in, the sheet is pulled downward (flattens it out)
2. The second action causes the rib cage to move upward and outward – this results in contraction of the intercostals muscles
which lie between the ribs
Inspiration (breathing in)
The volume of the lungs increases as the chest wall moves upward and outward, and the diaphragm moves downward
As the volume increases, pressure decreases; as the pressure decreases, air rushes in to equalize the pressure inside the lungs
The process of inspiration requires that muscles actively contract
Expiration (breathing out)
As the diaphragm relaxes, it pushes up to regain its shape
The intercostals muscles in the chest wall relax and the ribs move down and inward
These movements decrease the volume of the lungs, the pressure inside increases which pushes air out of the lungs until the
internal and external pressure are equal once more
Breathing out requires no muscle contraction – it is just the result of muscle relaxation
Lung Capacity
Healthy adult – average 14-20 breathes per minute
The amount of air moved by a normal individual breathing while at rest is called the tidal volume – this is only a portion of the
potential lung capacity
If you forcibly push out as much air as you can, the air you remove is called the expiratory reserve volume
Similarly the amount of extra air you can forcibly pull in is the inspiratory reserve volume
These three volumes together make up the vital capacity of the lungs
No matter how hard you try to push air out of the lungs, there will always be a small amount left in the spaces and tubes – called
residual air capacity
Structure and Function
The structure and function of the respiration tract is to maximize air exchange, and minimize foreign particles from entering the
lungs.
Repiratory system with the Circulatory System
Respiratory system brings oxygen into the body
Oxygen will cross the membranes, enter the bloodstream, and be transported to the cells which require oxygen for their activities
Unit X: HIV/AIDS
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The Human Immunodeficiency Virus (HIV) is the virus that causes Acquired Immunodeficiency Syndrome (AIDS).
HIV attacks the immune system
HIV leaves infected people vulnerable to opportunistic infections and cancers.
For most people, there are at least 10 years between when they get infected and when they get diagnosed.
HIV is spread by:
• Unprotected sexual intercourse (vaginal, anal, oral)
• Shared needles or equipment for injecting drugs
• Unsterilized needles for tattooing, skin piercing or acupuncture
• Pregnancy, delivery and breast feeding (from an HIV-infected mother to her infant)
• Occupational exposure in health care settings
HIV is NOT spread by:
• Casual, everyday contact
• Shaking hands, hugging, kissing
• Coughs, sneezes
• Giving blood
• Swimming pools, toilet seats
• Sharing eating utensils, water fountains
• Mosquitoes, other insects, or animals
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People with HIV can live for many years with no external sign or symptom of the disease, and may unknowingly infect others.
The only way to know if you have the virus is to have an HIV blood test.
When the body can no longer fight infection, the disease is known as AIDS
The infections associated with AIDS are called "opportunistic" because they take advantage of the body's weakened immune
system.
It is the opportunistic infection, and not AIDS, that causes death.
At the end of 2002, Health Canada estimated there were approximately 56,000 people in Canada living with HIV or AIDS
Almost a third of them were not aware that they were infected.
Geneticists have traced the arrival of AIDS in America to a single person who came from Haiti in 1969.
Unit XI: Reproduction
Female Anatomy
• Ovary
– Ova (eggs) produced here
• Females are born with all their eggs; they do not produce more after birth
– Estrogen, main female hormone produced here (as well as in the pituitary gland)
– Progesterone produced here (hormone of pregnancy)
• Fallopian Tubes
– Two thin tubes near, but not attached to the ovaries
– Where fertilization takes place
• Uterus
– Pear shaped organ with muscles that stretch to allow baby to develop.
– Lining of uterus (endometrium) thickens with blood-rich tissue each month to prepare for potential pregnancy. If this
doesn’t take place, the lining sheds during menstruation.
• Vagina
– Birth canal and where menstrual blood leaves the body.
– Muscular organ, able to stretch to allow for the baby to leave.
– Partially closed by a thin membrane (hymen) that may stretch or tear during first intercourse or physical activity.
• Cervix
– Opening of uterus into vagina.
– Located at inner end of the vagina
– Mucous located here to prevent bacteria and viruses from entering the uterus.
Hormones in Female Reproduction
• FSH (follicle stimulating hormone)
– produced in the pituitary gland at the base of the brain.
– Cause follicles/ovum (eggs) to mature
– Stimulate estrogen production
• LH (luteinizing hormone)
– Produced in the pituitary gland
– Causes the release of the ovum from the ovary
– Causes the production of progesterone
• Estrogen
– Increases the size of the oviducts, uterus and vagina
– Responsible for secondary sexual characteristics including fat in breasts and the development of a duct system,
broadening of the pelvis, soft and smooth skin, fat in buttocks and thighs, pubic hair and sexual desire.
• Progesterone
– Pregnancy hormone
– Thickens the lining of the uterus
– Calms muscular contractions of the uterus
• FSH is released at the beginning of the cycle, causing the ovum to mature.
• LH levels spike around the 13th day causing the release of the egg. This is ovulation.
• If fertilization does not take place, the lining of uterus will shed, with the egg, ending the cycle.
Male Reproductive Anatomy
• Penis
– Responsible for urination and sexual intercourse
– Contains spongy tissue that fills with blood when aroused. This causes the penis to harden.
– Foreskin is on the end of the penis. Some people have it removed in an operation called circumcision.
• Scrotum
– Contains two testes.
– Temperature sensitive to protect sperm
– Holds testes close to the body when cold and away when warm
– Has sweat glands
• Testes
– Sperm by the seminiferous tubules
– Leydig cells stimulate production of testostrone
– Testes formed in abdomen before birth. Descend during fetal or post-natal life. May take months to get to the right
place.
• Epididymis
– Store sperm until they are mature
• Vas deferens
– Tube that leads from epididymis to urethra.
• Prostate gland
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•
– Provides a fluid that protects sperm from harsh acids in the vagina
Seminial vesicles
– Produces fructose (sugar) for sperm
Copwer’s glad
– Produces a clear lubricating fluid
Hormones in Male Anatomy
• FSH (follicle stimulating hormone)
– Regulates sperm production
• LH
– Prompts the Leydig cells to produce testosterone
• Testosterone
– Causes the development of the male sex organs
– Responsible for facial, armpit and pubic hair; bone growth; and, muscle development