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THE NERVOUS SYSTEM
FUNCTION:
The nervous system controls & coordinates everything
in the body. This includes all movement and all of
the activities of the organs & organ systems.
MAJOR PARTS OF THE NERVOUS SYSTEM
1.
2.
3.
Brain: The controls center of the nervous system, and
the whole body
Spinal cord: Carries messages to and from the brain.
Neurons (nerves) are the special cells that carry the
messages through the body.
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A neuron is long and thin to send messages through the
body
The nervous system sends electrical signals throughout
the body.
A signal travels through several neurons to the brain.
The brain then sends messages back out to the rest of
the body.
Brain
Spinal Cord
Nerves
The Circulatory System:
Function:
The circulatory system & respiratory system work
together to supply cells with the oxygen and nutrients
they need to stay alive.
The Main Parts:
1. The heart
a)
Atria: 2 upper chambers, receive blood from the body
b) Ventricles: 2 lower chambers, pump blood out of
heart
c)
Valves: Regulate the flow of blood through the heart
2. Blood vessels:
a) Arteries: Carry oxygenated blood to the heart
b) Veins: Carry deoxygenated blood to the heart
c)
Capillaries: The smallest, bring nutrients & oxygen to
the tissues & absorb carbon dioxide & other waste
products from them
3. Blood:
a)
Red blood cells: Contain hemoglobin & carry oxygen
b) White blood cells: Infection fighters
c)
Platelets: Clot blood
d) Plasma: The liquid part of blood
The Flow of Blood Through the Body:
Heart  Arteries  Capillaries  Veins  back to heart
Diagram the Flow of Blood:
The Respiratory System
Function:
The basic function of the human respiratory system is the
exchange of oxygen & carbon dioxide between the
blood, air and tissues. In addition, air entering the
respiratory system is warmed, moistened & cleaned
before it enters the lungs.
Main Parts:
1.
Nose (& mouth): air enters here
2.
Pharynx: serves as a passageway for both AIR & food
3.
Epiglottis covers the entrance to the trachea when
you swallow (so food does not go into lungs
Define:
1. Gas exchange: Oxygen diffuses into the blood &
carbon dioxide diffuses from the blood out into the
lung
2.
Breathing: The taking in of oxygen and release of
carbon dioxide waste into the air
3.
Diaphragm: Muscle that controls breathing by
moving up & down
Flow of air through the body:
Nose Trachea  Bronchi  Bronchioles
 Alveoli of the lungs
4.
5.
6.
7.
Larynx: contains two elastic folds of tissue called
vocal cords
Trachea: also known as the windpipe
Bronchi: two large passageways in the chest cavity,
each bronchus leads into one the lungs
Alveoli of lungs: tiny air sacs (like grapes) where gas
is exchanged
Nose
Mouth
Label the Diagram of the Respiratory System:
A
I
F
E
B
Nose
Bronchioles
Trachea
Larynx
Mouth
J
C
H
D
G
Diaphragm
Pharynx
Bronchus
Epiglottis
Lungs
The Reproductive Systems:
 The main function of the reproductive
systems is to make egg and sperm cells
which will combine to make a zygote
(offspring)
Male Reproduction
 The function of the male reproductive
system is to produce and deliver sperm.
 Sperm are made in the testes through the
process of meiosis.
 In human males, sperm are haploid & have 23
chromosomes
 testes: 2 walnut sized organs that make sperm
 scrotum: 2 pouches that each contain one testis outside
the body.
 vas deferens – tube that sperm travel through when they
are released from each testis.
 urethra – tube that connects the 2 vas deferens and travels
through the penis.
 Both sperm & urine travel through the urethra
 During ejaculation (sperm being released from the penis)
sperm mix with a seminal fluid-
together sperm and fluid make up semen.
• Male Reproductive System
Urinary bladder
Vas deferens
Pubic bone
Seminal vesicle
Urethra
Rectum
Penis
Prostate gland
Epididymis
Testis
Scrotum
Bulbourethral
gland
1.
2.
3.
THREE FUNCTIONS OF THE
FEMALE REPRODUCTIVE SYSTEM
To produce eggs
To receive sperm
Provide an environment that a baby can develop in
How are eggs produced & released in females?
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ovaries: 2 ovaries are where eggs are made through
meiosis. 1 egg is released each month called
ovulation
fallopian tube: tube the egg travels through one it is
released from the ovary. (also called oviduct) there
are 2 fallopian tubes.
uterus: fist sized organ where an embryo grows.
vagina: passageway to the outside of the body
- baby is born through this passageway and
sperm are deposited here
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cervix: small opening at the bottom of the uterus
which leads into the vagina. Opens when a baby is
born. Otherwise small so menstrual blood can exit
the body.
If a successful pregnancy is to occur, the egg must be
fertilized by the sperm in the fallopian tube/oviduct.
The fertilized egg is called a zygote and must then
implant into the uterus, where it will develop for 9
month
If fertilization hasn’t occurred, the egg then travels
into the uterus, through the cervix and into the vagina
and out the body.
cervix
THE MUSCULAR SYSTEM FUNCTIONS:
 Muscle allow organs & bones of the body to move.
 The fibers that make up muscle, “contract”. The
contraction makes the whole muscle shorter which
allows them to move organs and bones.
3 TYPES OF MUSCLE
1. Skeletal: Attaches to bone & allows for movement
2. Smooth: Found in the walls of the stomach, intestines
& blood vessels. Helps materials move through these
structures
3. Cardiac: Makes the heart
beat to send blood to the
body.
HOW DO MUSCLES MOVE BONES?
 Muscles contract and cause bones to move.
 Tendon: Attaches a muscle to a bone
 Muscles work in pairs to cause movement:
Ex: Bicep contracts & tricep relaxes  arm bends
Bicep relaxes & tricep contracts  arm straightens
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Functions of the skeletal System
- supports the body
- protects the organs
- allows the body to move
- makes blood cells
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Parts of the skeletal system
- bones
- ligaments
- tendons
- cartilage
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There are 206 bones in the human body.
Bones are living tissue that grow and need
blood.
Bones have blood vessels inside of them and
are made of cells
Types of Bone Tissue:
1. Compact: Layer of hard bone that covers all bone
2. Spongy: Surrounded by the compact bone, it has
many holes & spaces in it. Makes bones lighter.
3. Bone marrow: Soft tissue inside of bones makes
blood cells
WHAT ARE JOINTS?
A joint is where 2 or more bones meet & allow for
movement
 Ball & socket: Shoulder & hip
 Hinge joint:
Elbow
 Pivot joint:
Neck
Joints are held together by a tough band of tissue called
ligament
Tough & flexible cartilage might cover the ends of a bone
to allow for smooth movement between bones
The Digestive System:
Function:
The digestive system converts food into simpler
molecules that can be used by the cells of the body.
The Parts of the Digestive System:
1. Key organs
a) Mouth – food is chewed & mashed into paste and
salivary glands secrete saliva which contains
enzymes
B.
C.
D.
E.
Esophagus Muscular tube that contracts, pushing
food into the stomach
Stomach Muscular sac that churns, continuing the
breakdown of food mechanically & chemically with
enzymes
Small Intestine long tube where most of the nutrient
molecules are absorbed into cells
Large Intestine Removes water from
undigested food material. Also called
the colon
2.
Accessory Organs
a) Pancreas Secretes hormones to control blood
sugar (insulin) and enzymes to digest starch,
fat, protein.
b) Liver Produces bile which dissolves fat
c) Gall bladder Stores bile before entering small
intestine
Define:
1.
Mechanical digestion: Physical breakdown of food
into smaller pieces by the teeth & churning stomach
2.
Chemical digestion: Enzymes chemically break food
into smaller pieces in the mouth, stomach & small
intestine
3.
Villi: Finger-like projections in the small intestine
which increase the surface area so more nutrients
can be absorbed
The Excretory System:
Function:
The basic function of the human excretory system is the
removal of waste from the cells and body. The skin
excretes excess water and salts in the form of sweat.
The lungs excrete carbon dioxide. The kidneys play a
major role in excretion and remove waste products
from the blood, maintain blood pH and regulate the
water content of the blood and, therefore homeostasis.
THE MAIN PARTS:
1. Kidneys = located on either side of the backbone and
partially protected by the ribcage
2. Blood enters the kidney and is cleaned and filtered.
3. Urea (a toxic substance), excess salts, and water are
removed from the blood and form urine.
4.
Once filtered, clean blood leaves the kidney and
returns to circulation.
5. Nephrons = the functional, blood-filtering units of the
kidney
6. Ureters= 2 tubes, one leaving each kidney, carry urine
to the urinary bladder
7. Bladder= a saclike organ where urine is stored before
being excreted
8. Urethra= a tube that carries urine form the bladder &
releases it from the body
DEFINE:
Urea = Nitrogen containing waste made by the body
Dialysis = Blood is removed from the body, cleaned by a
machine & then returned to the body
UREA REMOVAL FROM THE BODY:
Kidneys  Ureter Bladder  Urethra released
from body
A DIAGRAM OF THE EXCRETORY SYSTEM:
D urethra
A kidney
B ureter
C urinary bladder