Transcript Unit 1 Cells and System

1.1 Observing Living Things
• Living things can survive in almost any kind of
environment.
• Living things have features that help them survive.
• For example,hummingbirds
can beat their wings up to
80 times per second, allowing
them to hover and change
direction rapidly.
• All living things have needs that
must be met if they are to survive.
See pages 8 - 9
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Characteristics of Living Things
• There are 5 characteristics of living things:
 Living things respond to their environment
 Living things need energy
 Living things grow
 Living things reproduce
 Living things must get rid
of waste
See page 10
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Examining Very Small Living Things
• The microscope is used by scientists to observe very
small unicellular and multicellular living things.
• Early microscopes were built in the late 1600’s.
• Anton van Leeuwenhoek was one
of the first people to build a
microscope.
• He could magnify up to 250x, and
used it to observe microscopic
living things.
Water flea (Daphnia)
See page 11
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Compound Light Microscope
• The compound light microscope has
two sets of lenses that magnify an image.
• Each of the objective lenses has a
different magnification power.
 Low power = 4x objective
 Med power = 10x objective
 High power = 40x objective
• Multiply the objective by the
eyepiece for total magnification.
 Example: High Power = 40 x 10 = 400 x
Do you know all the compound microscope parts?
See pages 12-13
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Resolving Power
• The ability to distinguish between two dots or objects
that are very close together is called resolving power.
• The human eye has a certain resolving power. You can
see the individual dots in diagrams A, B and C. The
human eye does not have the resolving power to see
the dots in diagram D.
Can you think of ways to increase resolving power?
Take the Section 1.1 Quiz
See page 14
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1.2 Cells
• An analogy is a way to understand new ideas by
making a comparison.
• A factory can be used as an analogy for the cell.
• Parts of the cell that allow the cell to survive are called
organelles.
• Organelles take up about 5 to 30 percent of the cell.
The rest of the cell consists of water.
How is the Newo colony similar to
a factory?
See pages 22 - 24
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The Functions of Cell Organelles
• The cell membrane protects the cell and regulates the movement
of particles in and out of the cell.
• Cytoplasm, the jelly-like substance within the cell, contains
organelles, water, and other life supporting materials.
• The nucleus:
 controls all the activities within the cell.
 contains deoxyribonucleic acid (DNA).
See page 25
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Energy in the Cell
• The mitochondria are the organelles that produce
energy in the cell.
• When the cell changes chemical energy, in the food
we eat, to energy the cell can use, it is called cellular
respiration.
• The total of all the chemical reactions that take place
in our cells is called our metabolism.
See page 26
Cellular Respiration
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Organelles for Assembly, Transport, and Storage
• Proteins are essential for all life
and are assembled by the
ribosomes.
• Proteins then pass through the
endoplasmic reticulum and are
placed in vesicles by the Golgi
body.
• Vacuoles are temporary
storage compartments.
• Lysosomes break down food
particles, cell wastes, and
worn-out organelles.
See pages 28-29
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The Difference Between Plant and Animal Cells
• Plant cells have two parts that are not
found in animal cells:
 Cell Wall
 protects the cell and gives cell shape
 Chloroplasts
 change the Sun’s energy into chemical
energy
Locate the cell wall and
chloroplast
See pages 29-30
Photosynthesis
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Cell Theory
• The cell is the basic unit of life.
• All organisms are composed of one or more cells.
• All cells come from other living cells.
See pages 31-32
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Prokaryotic and Eukaryotic Cells
Cells are classified into two groups:
Prokaryotic cells have
organelles that are not
surrounded by membranes.
Eukaryotic cells have
organelles that are
surrounded by
membranes.
Eukaryotic cells are
usually larger than
prokaryotic cells.
See page 32
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Bacteria and Viruses
Bacteria are prokaryotic cells.
• Some bacteria cause diseases such as:
tuberculosis and strip throat.
• Helpful bacteria are used to make food
such as: cheese and yogurt.
• Bacteria are often grouped by the shape of
their cells.
Viruses are not living.
• HIV, chicken pox, and the flu are examples
of viruses.
• Viruses do not contain any cell organelles
but reproduce by using a host cell.
See pages 33 - 34
Take the Section 1.2 Quiz
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1.3 Diffusion, Osmosis, and the
Cell Membrane
• Diffusion is the movement of particles from an area of
higher concentration to an area of lower
concentration.
• Concentration is the amount of substance in a given
space.
• The smell of fresh baked bread “spreading”
throughout the room is an example of diffusion.
The diffusion
of ink in water.
See pages 40 - 41
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Diffusion and the Cell Membrane
• The cell membrane is a selectively permeable membrane.
 This means that it has many small openings that let some substances
pass through it but not others.
• One way that substances can move through the cell membrane is
by diffusion.
• When the concentration on both sides of the membrane is the
same, it is called equilibrium.
See page 42
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Osmosis
• Osmosis is the diffusion
of water through a
selectively permeable
membrane.
• Osmosis occurs when
water particles move
from a higher
concentration to a
lower concentration.
See page 43
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Osmosis and the Cell
• Cells contain water and need this water to survive.
• Osmosis is how the cell gains and loses its needed
water.
Explain how placing this wilted
flower in water will cause the flower
to “straighten up”.
See pages 43 - 44
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Examples of Osmosis
Example 1: Equal movement of water in and out of cells
See page 45
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Examples of Osmosis
Example 2: More water moving into cells than is moving out
See page 45
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Examples of Osmosis
Example 3: More water moving out of cells than is moving in
Take the Section 1.3 Quiz
See page 45
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2.1 Body Systems
• A system is made of parts that work
together as a whole.
• The Characteristics of Systems
 1. A system is made of individual parts that
work together as a whole.
 2. A system is usually connected to one or
more systems.
 3. If one part of a system is missing or
damaged, the system will not function well
or may not function at all.
A stereo system
has many parts
that work
together.
See pages 54 - 55
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Systems of the Human Body
Eleven systems of the human body
•Circulatory System
•Transports blood, nutrients, gases, and
wastes
•Digestive System
•Breaks down food and absorbs the nutrients
•Respiratory System
•Exchanges gases in lungs and tissues
•Excretory System
•Removes liquid and gas wastes from the body
•Immune System
•Defends body against infections
•Endocrine System
•Manufactures and releases hormones
See pages 56 - 57
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Systems of the Human Body
More Systems…
•Reproductive System
•Includes reproductive organs for producing
offspring
•Integumentary System
•Creates a waterproof barrier around the body
•Skeletal System
•Supports, protects, and works with muscles to
move parts of the body
•Muscular System
•Has muscles that work with the bones to move
parts of the body
•Nervous System
•Detects changes in the environment and
signals the body to carry out a response
See pages 56 - 57
(c) McGraw Hill Ryerson 2007
Organ Systems
• An organ system has one or more organs that perform
specific body functions.
 For example your heart is part of the circulatory system.
• The four levels of organization within the human body
are:
cell
tissue
organ
organ system
See page 58
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Tissues: The Foundation of Body Systems
• Tissue is a group of cells that have
the same structure and function.
• Four types of body tissue:
 Muscle tissue
 Assists in body movement
 Nerve tissue
 Transfers signals to and from brain
 Connective tissue
 Holds together and supports other
tissue
 Epithelial tissue
 Covers the surface of organs and
body
Take the Section 2.1 Quiz
See pages 58 -59
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2.2 The Digestive and Excretory Systems
• Nutrients are substances the body requires for energy,
growth, development, repair, or maintenance.
• We get nutrients from what we eat and drink.
•Four Food Groups
•Grain products
•Vegetables and fruit
•Milk products
•Meat and alternatives
See pages 64 - 65
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Types of Nutrients
• Carbohydrates
 The bodies quickest source of
energy
 Examples include: rice, vegetables,
cereal, and bread
• Proteins
 Used to build parts of your bodies
muscles, skin, hair, and nails
 Examples include: fish, meat, eggs,
nuts, soy products
See pages 66 - 69
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Types of Nutrients
• Fats
 Used to build cell membranes and can
be stored for future energy.
 Examples include: butter, vegetable oil,
and meat
• Minerals and Vitamins
 Needed in small amounts to perform
various body functions
 Two common minerals and vitamins
are calcium and vitamin D
Water is not a nutrient but
is necessary for life!
See pages 66 - 69
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The Four Stages of Digestion
•
•
The process in which food is broken
down, nutrients are absorbed, and
wastes eliminated is called digestion
and occurs in the digestive system.
The fours stages of digestion are:




Ingesting
Digesting
Absorbing
Eliminating
See page 70
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Stage 1: Ingesting
•
Ingesting, or ingestion, means
to bring food into the body. This
is the starting point of the
digestive process.
See page 71
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Stage 2: Digesting
The Mouth
•
•
•
•
Mechanical digestion occurs when
your teeth and tongue break food
into small enough pieces to swallow.
Each small piece of food is called
bolus.
Chemical digestion occurs when
saliva begins to break down the
bolus.
An enzyme in your saliva begins to
break down simple and complex
carbohydrates.
See page 71
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Stage 2: Digesting
The Esophagus
•
•
•
When you swallow, your food
enters the esophagus.
The esophagus is a long
muscular tube that carries
food to your stomach.
The bolus is pushed through
the esophagus in a process
called peristalsis.
See page 72
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Stage 2: Digesting
The Stomach
•
•
•
•
Inside the stomach is gastric
juice, which is very acidic.
The stomach walls are lined with
mucus to protect the tissue from
being damaged by the acid.
An enzyme called pepsin, present
in gastric juice, breaks down
protein.
The bolus that enters your
stomach breaks down into a liquid
called chyme.
See page 73
(c) McGraw Hill Ryerson 2007
Stage 2: Digesting
The Small Intestine
•
•
•
•
The first metre of the small
intestine is called the
duodenum.
The pancreas adds enzymes
that help break down the
carbohydrates, protein, and fat
in the chyme.
The liver produces bile which is
stored in the gall bladder.
Bile breaks the globs of fat into
smaller droplets.
See page 74
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Stage 3: Absorbing
The Small and Large Intestine
•
•
•
Absorption is the process in
which nutrients and water are
absorbed by the small and
large intestine.
The small intestine is covered
with villi to help increase the
rate at which nutrients are
absorbed.
The large intestine absorbs
water and some minerals.
See page 75
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Stage 4: Eliminating
•
•
•
Any solid material, undigested by
the end of the large intestine is
called feces.
Feces are stored in the rectum
until they are eliminated through
the anus.
Liquid and gas wastes are
removed by your excretory
system.
 The main organs in your excretory
system are your kidneys and your
bladder.
See page 76
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Eating Disorders
• Anorexia nervosa is a
disorder when a person
severely restricts what
they eat.
• Bulimia nervosa is a
disorder when a person
eats large amounts of
food and then vomits or
takes laxatives to get rid
of the food before it is
completely digested.
Take the Section 2.2 Quiz
See page 77
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2.3 The Circulatory and Respiratory Systems
• The circulatory system consists of the
heart, arteries, capillaries, and veins.
• Your heart is a pump that pushes
approximately 4 L of blood through your
body every minute.
• The main purpose of the respiratory
system is to exchange gases.
• The main organ of the respiratory system
are the lungs.
See pages 82 - 83
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Taking a Closer Look at the Heart
• The heart pumps blood throughout
the body.
• The heart has four chambers:
 Left atrium
 Blood arrives from your lungs
 Right atrium
 Blood arrives from your body
 Left ventricle
 Pumps blood to your body
 Right ventricle
 Pumps blood to your lungs
• Between each of these chambers is
a valve.
See page 84
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The Circulatory System
• The circulatory system moves blood throughout the body.
• There are three types of blood vessels:
 Arteries
 Carry oxygenated blood away from your heart
 Capillaries are tiny blood vessels
 Responsible for transfer of
oxygen and nutrients into the body
cells and collecting waste
from the cells.
 Veins
 Blood containing waste
products returning to the heart.
See pages 85 - 86
(c) McGraw Hill Ryerson 2007
The Circulatory System
• Starting with the right atrium, try
placing the following structures in
the correct order that blood flows
through the body.
 Left ventricle Body
 Right atrium
Left atrium
 Lungs
Right ventricle
See pages 87 - 88
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The Components of Blood
• About 55% of blood is a liquid called
plasma.
 Contains proteins, minerals, and other
substances.
• Red blood cells carry oxygen from the
lungs to the cells.
• White blood cells fight infection.
• Platelets are important for clotting
blood.
See pages 88 -89
(c) McGraw Hill Ryerson 2007
The Respiratory System
• The respiratory system moves
oxygen into your body and carbon
dioxide out of your body.
• When you inhale, air is filtered by
tiny hairs called cilia.
• Air passes through your larynx and
continues down your trachea
towards your lungs.
• At the base of the trachea are two
tubes called bronchi.
• Bronchi branch into smaller air
tubes called bronchioles.
See page 90
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Gas Exchange in the Alveoli
• There are millions of alveoli at the
ends of the bronchioles, and this
is where gas exchange takes
place.
• Oxygen and carbon dioxide move
back and forth between the alveoli
and the surrounding blood
vessels.
See page 91
(c) McGraw Hill Ryerson 2007
Smoking
• Smoking may cause both respiratory disease and heart disease.
• Respiratory diseases could include emphysema and lung cancer.
 Emphysema causes the alveoli walls to lose their elasticity. This may
make breathing very difficult.
• Smoking also destroys the cilia lining your respiratory system.
Take the Section 2.3 Quiz
See page 92
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3.1 The Immune System
• Infectious diseases are
caused by pathogens.
 Pathogens are
“germs” or diseasecausing invaders
that enter the body.
• The immune system
attacks and destroys
these disease-causing
invaders.
See pages 100 - 101
(c) McGraw Hill Ryerson 2007
First Line of Immune Defense
There are two lines of immune defense.
First line of Defense
• The skin is a physical barrier that
stops most pathogens from entering
the body.
• The sweat and oils on skin are slightly
acidic.
• Gastric juices in your stomach can
destroy some pathogens.
• Mucus and cilia in your nose prevent
pathogens from entering your
respiratory system.
Mucus cells
See page 102
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Second Line of Immune Defense
If a pathogen makes it past the first line
of defense.
Second line of Defense
• The second line of defense includes
two types of immune response:
 Innate Immune Response
 A response you are born with.
 Acquired Immune Response
 A highly specific attack on a
pathogen.
See page 102
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Innate Immune Response
• The response is quick and general, or
non-specific.
 Response is the same for any type of
invader.
• First action is a flow of fluid into site of
infection.
 Causes fever, swelling, and redness in
area.
 The swelling and redness is called
inflammation.
• Increase in the types of white blood
cells called phagocytes.
 Phagocytes destroy pathogens.
Inflammation of an
infected toe.
See page 103
(c) McGraw Hill Ryerson 2007
Acquired Immune Response
• Highly specific attack on a specific
pathogen or antigen.
 An antigen is a non-living particle or
substance that body cannot recognize.
• All acquired immune responses help
give you active immunity.
 This means your body remembers how to
fight a pathogen that has infected it before.
 This is why you get diseases such as
chicken pox only once.
Chicken Pox
See page 104 - 105
(c) McGraw Hill Ryerson 2007
Acquired Immune Response
B cells in action
• First process in the acquired immune response:
 B cells recognize antigens present in the body.
 Produce particles, called antibodies, used to fight antigens.
See page 104
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Acquired Immune Response
T cells in action
• Second process in the acquired
immune response:
• Two types of T cells:
 Helper T cells
 Recognize antigen or pathogen
and activate B cells
 Killer T cells
 Recognize and destroy antigen or
pathogen without B cells.
See page 104
(c) McGraw Hill Ryerson 2007
Immune Response (4 Steps)
The response of your immune system to disease-causing organisms
can be divided into four steps: recognition, mobilization, disposal,
and immunity.
See page 105
Take the Section 3.1 Quiz
(c) McGraw Hill Ryerson 2007
3.2 Factors Affecting the Immune System
• Vaccines are weakened versions of a
disease pathogen that are given to
people to protect them from getting
the disease later.
• Vaccines allow your body to create
antibodies against the disease.
• Boosters are needed for some
vaccines to extend the immune
system’s memory.
See pages 110 - 111
(c) McGraw Hill Ryerson 2007
Disorders of the Immune System
Allergies
• An allergy is an unusually high
sensitivity to some substance.
• Any substance that causes an allergic
reaction is called an allergen.
 Common allergens are: milk, pollen, and
dust.
• Body releases chemical called
histamine to fight allergen.
 Common symptoms include a runny nose
and watery eyes.
Dust Mite
• Severe allergies can cause an
anaphylactic shock.
See pages 112 - 113
(c) McGraw Hill Ryerson 2007
Disorders of the Immune System
AIDS – Acquired Immunodeficiency
Syndrome
• AIDS is caused by a virus called HIV
• HIV attacks the immune system by
infecting Helper T Cells.
 When other pathogens or antigens enter
the body the immune system can’t
activiate Killer T cells or B cells.
• AIDS is transmitted by blood and
semen.
Illustration of HIV
See pages 113 - 114
(c) McGraw Hill Ryerson 2007
Taking Care of Your Immune System
Important steps you can take to help your immune
system stay healthy.
Take the Section 3.2 Quiz
See page 114
(c) McGraw Hill Ryerson 2007