Download Unit 3: Cells to Systems

UNIT 3: CELLS TO
SYSTEMS
Lesson 1:
What are
Cells?
Cells
A cell is the basic unit of structure and
function in a living thing.
 Very small, so a microscope is used to see them.
Organisms, or living things, can be made of
one cell or many cells.
 If there are more than one cell, the cells are
specialized and perform special jobs.
Cell Theory Scientists
Robert Hooke (1665) was one of the first
scientists to use a microscope.
 He observed a slice of cork and thought it looked
like it had tiny rooms, so he named them cells.
Matthias Schleiden (1838) – all plants are
made of cells.
Theodor Schwann (1839) – all animals are
also made of cells.
Cell Theory
 The cell theory has three parts:
1. All living things are made of cells.
2. All the processes of life take place in the cells.
3. New cells come from existing cells.
UNIT 3: CELLS TO
SYSTEMS
Lesson 1:
Cell Parts
What are cells made of?
Cells are made up of even smaller structures
called organelles.
Plants and animals share many of the same
organelles, but they have some that are special.
This is not the full list of organelles, but they
perform a great deal of the cell’s functions.
Shared Organelles
Cell membrane: thin covering surrounding the
cell and holding the parts of the cell together.
Nucleus: controls the cell’s activity (like a brain);
cell growth and reproduction
 Contains chromosomes, which holds an organism’s DNA.
Shared Organelles
Shared Organelles
 Cytoplasm: jelly-like substance that holds all the other
organelles.
 Mitochondria: release energy from food; “the mighty
mitochondria” – the powerhouse of the cell.
 Vacuoles: storage spaces for food, water, and waste.
 Plants have one large vacuole (central vacuole).
 Ribosomes: make proteins for the cell.
Shared Organelles
Only Plants
 Cell wall: an extra layer of protection; on the outside of
the cell membrane.
 Chloroplast: trap the sun’s energy and transforms it into
food for the plant through photosynthesis; makes the
plant green.
UNIT 3: CELLS TO
SYSTEMS
Lesson 2:
How do
cells work
together?
Cells to Systems
 The cell is the basic unit of life.
 Cells that perform the same function join together to
form tissues.
 Muscle tissue: contract and relax to move the skeleton
 Nervous tissue: brain/spinal cord and senses
 Connective tissue: bones, cartilage, tendons, and blood
 Epithelial tissue: body covering (skin) and organ lining
Cells to Systems
Tissues that work together join to form organs.
 Each organ plays an important role in survival.
Organs that work together form a system.
 There are ten major body systems. We will learn a few of
them.
The Human Body
Systems
The
Circulatory
System
The Circulatory System
Function: Transport oxygen, nutrients, and
waste through the body using the blood.
Major Structures: heart, veins, arteries,
capillaries, and blood.
The Heart
 an organ made of muscle tissue, about the size
of your fist.
 Located a little to the left of the middle of your
chest
 Has four chambers
 Left atrium
 Right atrium
 Left ventricle
 Right ventricle
The Heart – Blood flow
 The right and left side are separated from each
other to keep the blood on the correct path.
 The atria and ventricles are separated by four
valves, which act like trap doors – only letting blood
move forward.
The Heart – Blood flow
 The right atrium receives blood from the rest of the
body (no oxygen).
 Sends it to the right ventricle and into the lungs.
 The lungs put oxygen in the blood, and send it to
the left atrium.
 The left ventricle pumps the oxygen-rich blood to
the rest of your body.
The Heart – Blood flow
Blood
 The liquid part of blood is called plasma, and it is
mostly water.
 Platelets are tiny pieces of blood cells that help clot
blood.
 The solid part of blood contains red blood cells and
white blood cells.
 Red blood cells absorb oxygen from the lungs.
 White blood cells help fight infection by attacking
viruses/bacteria.
Blood Vessels
 Arteries: carries oxygen-rich blood from the left
ventricle to the rest of the body. (red)
 Capillaries: tiny blood vessels that connect arteries
to veins; collect waste from cells.
 Veins: return oxygen-poor blood to the right atrium
of the heart. (blue)
The Human Body
Systems
Caring for
the
Circulatory
System
Pulse
 You can measure your pulse on any major artery or
vein in your body.
 The two easiest places are on your wrist and on
your neck.
Pulse
 Walk up and down the stairs for one minute and take your pulse.
How does this compare to your resting hear t rate?
 Do jumping jacks for one minute and check your pulse again.
What is it now?
Blood Pressure
Blood pressure is the force that blood has
after it is pumped from the heart.
It always changes and is affected by activity,
rest, temperature, diet, posture, etc.
Measuring Blood Pressure
 Doctors use a sphygmomanometer to measure
blood pressure.
 Doctors compare the systolic pressure with the
diastolic pressure to get a blood pressure reading.
 An adult normal BP is 120/80
High Blood Pressure
High blood pressure is more commonly found
in adults, but kids can have it, too.
It can be associated with excess weight,
stress, an unhealthy diet, and not exercising.
Heart Health
 Exercise: get at least 30 minutes of exercise every
day.
 Healthy diet: eating a balanced diet will help keep
your heart healthy.
 Drinking water: water helps flush out unhealthy
materials from our body.
Balanced Diet
 Grains: breads, rice, pasta, and cereals can be found in this
food group. For the healthiest options, choose multi- or
whole grain options! 6-11 servings
 Fruit: apples, bananas, oranges, melons, and berries are just
a few options from this group. Mixed berries contain a high
amount of antioxidants! 2-4 servings
 Vegetables: carrots, lettuce, spinach, peppers, squash, and
beans are some healthy choices. The more colorful your
veggies are, the healthier they are for you to eat! 3-5
servings
Balanced Diet
 Meat/eggs/nuts: chicken, turkey, fish, eggs, legumes, and
almonds are some smart choices for this food group. Most of
these foods are high in protein, which helps build muscle. 23 servings.
 Dairy: milk, yogurt, and cheese are the main choices here.
Some of these foods are high in fat, so they shouldn’t be a
main entrée in your meals! 2-3 servings.
 Fats, oils, and sweets: It’s okay to have a treat every once in
a while, but they should be eaten sparingly. Healthy fats and
oils can be found in some foods like olives and avocados.
Balanced Diet
The Human Body
Systems
The
Respiratory
System
The Respiratory System
Function: Take in oxygen and remove carbon
dioxide.
Major Structures: trachea, bronchi, alveoli,
lungs, and diaphragm.
The Respiratory System
 The respiratory system begins working as soon as
your take a breath.
 The air goes in through your nostrils or your mouth,
and then travels down your trachea, or windpipe.
 On the way down, tiny hairs called cilia filter the air
to keep your lungs clean.
The Respiratory System
 The trachea split into two tubes called bronchi.
 Each tube leads into a lung.
 Each lung has even smaller branches of tubing,
called bronchioles, which each has a tiny air sac
called an alveoli at the end of it.
The Respiratory System
 The alveoli are surrounded by capillaries, which we
learned connect arteries and veins in the circulatory
system.
 At these tiny spaces, the two systems are joined
together to turn deoxygenated blood into
oxygenated blood.
More about the Lungs…
 Your lungs are not the same size; the left lung is
smaller to make room for your heart.
 They are protected by your rib cage.
 The diaphragm is beneath the lungs; it helps aid in
inhaling and exhaling.
 There are about 30,000 bronchioles (small tubes) in
each lung.
Did you know…
 Without your respiratory system, you would not be
able to talk?
 When you exhale, air moves by the larynx (voice
box) and through the vocal cords, causing vibrations
which lead to sound.
 Keeping your lungs healthy is important! Exercising
and not smoking are very beneficial for these hardworking organs!
The Human Body
Systems
The
Skeletal
System
The Skeletal System
Function: provide support, protect internal
organs, attachment site for muscles/help in
movement.
Structures: bones, tendons, ligaments, and
cartilage.
What are bones made of?
 Periosteum: the thin outer surface that contains
nerves and blood vessels.
 Compact bone: smooth and hard; the part you see
when you look at a skeleton.
 Cancellous bone: looks like sponge but is very hard.
What are bones made of?
 Bone marrow: the innermost part of the bone; thick
gel-like part that makes blood cells.
 Calcium makes your bones so tough.
Types of bones
 Long bones: bones in your legs and arms.
 Short bones: bones in your fingers and toes.
 Flat bones: in your shoulders and hips.
 Irregular bones: in your wrists and ankles.
Connective Tissue
 Ligaments: holds bones together by attaching to
each bone, almost like a rubber band.
 Tendons: tough bands that hold muscles onto
bones.
 Cartilage: soft tissue in ears, nose, and at the end
of bones when they form a joint.
Types of joints
 Bones are linked together at places called joints.
 Hinge joint: allow back and forth movement, like a
door.
 Elbows and knees
 Ball and socket joint: allows circular movement,
like a joystick.
 Shoulders and hips
Types of joints
 Fixed joints: these joints do not provide movement;
your skull is made of several pieces of bone joined
together by fixed joints.
 Pivot joints: this type of joint can be found in your
neck; it allows you to rotate your head.
Did you know…
The human body has 206 bones?
Each hand has 27 bones and your feet each
have 26 bones?
Your skull is made of 23 bones?
The Human Body
Systems
Bones
Your Core
 The spine makes up your backbone and is called
your vertebrae.
 There are 26 of these in total.
 They let you twist and bend, and hold your body upright.
 Your rib cage consists of usually 12 pairs of ribs
that are attached to your spine. The first 7 pairs
also attach in the front to a bone called a sternum.
Your Legs
 At the base of your legs is your pelvis, which
supports the spine and is made up mostly of your
hip bones.
 The large bones coming from your pelvis to your
knee are your femurs.
 Longest bone in the body.
Your Legs
 A fancy word for your knee is the patella.
 This connects your femur to two smaller bones that
make up your lower leg: the tibia and fibula.
Your Legs
 These two bones connect to your ankle (sometimes
called the tarsals), which connects it to the largest
bone in your foot – the talus.
 There are 52 bones in your feet and ankles
combined!
Your Arms
 Just like your legs start at your hip bones, your
arms begin at the shoulder bones.
 The shoulder blade is called your scapula, and it is
shaped like a triangle.
 The upper arm bone, called the humerus, is
connected to your scapula and your elbow.
Your Arms
 On the other side of your elbow are two smaller arm
bones, called the radius and the ulna.
 These two bones lead to the wrist, which is made up
of 8 smaller bones that lead to your hand.
 Sometimes called the carpals
 Do you know what scientists call your fingers (and
toes)?
 Phallanges!
Other bones
 Clavicle: collarbone; connects the shoulder to the
body.
 Skull/Cranium: head
 Mandible: the lower jaw bone.
The Human Body
Systems
The
Muscular
System
Other bones
Function: move the body
Structures: muscles and tendons.
What are muscles made of?
 All muscles are made up of elastic tissue that
allows them to contract and expand.
 Thousands of fibers make up each muscle.
 You have over 600 muscles in your body!
Types of Muscles
Smooth: usually in layers.
 Involuntary: you cannot control them.
 Stomach, heart, and eyes are a few examples.
 Your heart muscle is sometimes called the cardiac muscle,
or the myocardium.
Types of Muscles
 Skeletal: appear striped because they have light
and dark fibers making them up.
 Voluntary muscles: you control when and how they
move.
 The skeletal muscles work with your bones to
create the musculoskeletal system.
The Human Body
Systems
Major
Muscles
Important Muscles…
 Deltoid: move your shoulders
 Pectoralis/pectorals: upper chest muscles
 Abdominals: the muscles beneath your rib cage.
 Obliques: the muscles on the sides of your stomach
Important Muscles…
 Bicep: the muscle seen when you flex your upper
arm.
 Tricep: the muscle found on the backside of your
upper arm.
Important Muscles…
 Quadriceps: the muscles on the front of your thighs.
 Hamstrings: on the back of your thigh; a good test
of your flexibility!
 Gastrocnemius: just a fancy way of saying your calf
muscle (lower leg).
The Human Body
Systems
The
Nervous
System
The Nervous System
Function: controls just about everything you
do!
Structures: brain, spinal cord, nerves, and
neurons.
The Nervous System
 There are two major parts of the nervous system:
the central nervous system and the peripheral
nervous system.
 The CNS is the brain and spinal cord, and the PNS is
the sensory organs and nerves.
What are nerves?
Nerves are bundles of nerve cells, called
neurons.
These neurons are made up of two parts: the
axon and the dendrites.
What are nerves?
 Neurons are specialized and can send messages
from one neuron to another until it reaches the
brain.
 In between these neurons are tiny gaps called
synapses. Chemicals help the neurons pass the
message along.
The Spinal Cord
 Bundle of nerves that connects the brain to the rest
of the body.
 Protected by the vertebrae.
 The spinal cord runs down our back, and has spinal
nerves coming out between our vertebrae.
 It is only the width of a finger and about 43-45 cm
long.
The Human Body
Systems
The Brain
The Brain
Our brain is like the boss of the body, while
the rest of the nervous system helps it do its
job.
The brain is very complex, but we will break
it down into a few basic parts.
The Cerebrum
 The biggest part of the brain
 85% of its weight
 The “thinking” part of the brain – holds your
memory
 Two parts: the left side (math, logic, and speech)
and the right side (music, colors, and shapes)
 Controls voluntary muscles
The Cerebellum
Located at the back of the brain, below the
cerebrum.
Controls balance, movement, and
coordination.
The Brain Stem
 Connects the rest of the brain to the spinal cord.
 In charge of all of the functions you need to do to
stay alive, like breathing, circulating blood, and
digesting food.
 Sorts and organizes all of the messages being sent
to your brain.
The Hypothalamus
 Remember how we said your body has the ability to
maintain homeostasis, or constant temperature?
 This is why! The hypothalamus knows your body
needs to be around 98.6 F.
 If you’re too hot, you sweat. When you’re too cold,
you begin to shiver.
The Human Body
Systems
The
Integumentary
System
Skin
 Skin, along with your hair and nails, make up your
integumentary system.
 Skin keeps germs out, keeps water from leaving or
entering the body, and can help control body
temperature.
Skin Layers
 Epidermis: the top layer of the skin; can be very thin
(eyelids) or thick.
 Dermis: the inner layer of the skin; contains hair
follicles, sweat glands, blood vessels, and nerve
endings.
 Nerve endings: sense touch, heat, cold, pain,
pressure, and vibration.
Hair
Hair helps to keep you warm, but it also
helps to protect your scalp from injury and
blocks the sun from harming you.
The Human Body
Systems
The
Digestive
System
The Digestive System
Function: breaks down food into nutrients
and gets nutrients into the blood.
Structures: mouth, esophagus, stomach,
intestines, liver, gallbladder, and pancreas.
The Digestive System
 Saliva in your mouth moistens food and begins to
break it down into sugar.
 When you swallow food, it travels down the
esophagus (~10 in. tube) that leads to the stomach.
 Gastic juice/acid in the stomach breaks food down even
more.
The Digestive System
 After a few hours, food moves into the small
intestine, where the digestion process is completed.
 The villi in the sm. intestine collect the nutrients to
send them into the blood stream.
 The small intestine is about 22 feet long!
The Digestive System
 Food that is not broken down will pass into the
large intestine where it, along with other waste
products, are expelled from the body.
 The large intestine is wider than the small intestine,
but only about 5 feet long.
Other Important Organs…
 Liver: produces bile, which breaks down fats into
more easily digested particles.
 Gallbladder: stores bile until it is needed.
 Pancreas: produces fluid that neutralizes stomach
acid and chemicals that help finish digestion.
Other Important Organs…
 Liver: produces bile, which breaks down fats into
more easily digested particles.
 Gallbladder: stores bile until it is needed.
 Pancreas: produces fluid that neutralizes stomach
acid and chemicals that help finish digestion.
Digestive Health
To keep your digestive system working in a
happy way, drink plenty of water and eat
foods that are high in fiber – most fruits,
veggies, and whole grains!
The Human Body
Systems
The
Excretory
System
The Excretory System
Function: removing wastes from the blood
and the body.
Structures: liver, kidneys, nephrons, ureters,
bladder, and urethra; sweat glands.
The Excretory System
 Blood is carried into the kidneys (most people have
2) to be filtered by the renal arteries. The blood
contains ammonia/urea.
 Each kidney has more than 1 million nephrons
inside of it. These act as mini-filters to clean waste
out of the blood.
The Excretory System
 When the urea is filtered, it combines with water to
form urine.
 The urine travels in tubes called ureters that
connect the kidneys to the bladder.
 The bladder stores the urine until it is full, and then
pushes it through the urethra and out of the body.
The Sweat Glands
 We also get rid of excess materials when we sweat.
 Our bodies have an amazing ability to maintain
homeostasis – stable temperature – through
sweating.
 Heat and sweat are released from our bodies.