Transcript organ system

LEVELS OF CELLULAR
ORGANIZATION
and
BODY SYSTEMS
Reproduction, Respiratory, Circulatory, Digestion
and Excretory
VOCABULARY

Student copy

Completed copy
BIG
LEVELS OF CELLULAR
ORGANIZATION
ORGAN SYSTEM: Two or more organs
working together to perform a specific
function/job for the organism
ORGANS: Tissues work together to
perform a specific activity
TISSUES: Similar cells
working together to do the
same functions/jobs.
SMALL
CELLS
WHAT IS TISSUE?
 When
referring to the body, tissue is a
group of similar cells performing the
same or similar function.
ORGANS & ORGAN SYSTEMS

Organ is a group of similar tissues that perform
a similar, specific, and often complex function.

Types of Organs


Heart, Liver, Kidneys, Brain, Stomach, etc.
An organ system is a group of organs that work
together to perform a major function.

The human body has over 9 different major organ
systems:
Nervous, Circulatory, Respiratory, Digestive,
Excretory, Immune, Muscular, Skeletal, & Endocrine.
Major Organ Systems
Circulatory System: distribution system of the body;
delivers blood, water, & other necessary nutrients to
the parts of the body where they are needed.
 Digestive System: body system responsible for the
breakdown & absorption of nutrients and minerals
in food & drink.
 Endocrine System: body system that controls &
regulates certain chemically controlled processes in
the body.
 Example: Bone growth & hormone release during
puberty
 Excretory System: body system that removes waste
from the body
 Immune System: body system that fights off foreign
invaders, infections, & disease.
 Muscular System: body system responsible for
movement.
 Nervous System: body system that processes
external & internal stimuli & controls the body
responses as well as other bodily functions.

ORGAN SYSTEMS- CONTINUED
Respiratory System: body system responsible
for the gas exchange process; inhalation of
oxygen and exhalation of carbon dioxide.
 Skeletal System: body system provides a
framework for the body; provides protection to
internal organs; also works in conjunction with
the Muscular System to provide movement.
Often more than 1 Organ System works together to
accomplish a given task.
 Examples:
 Waste removal: Digestive, Excretory &
Circulatory
 Breathing: Respiratory & Circulatory.
 Movement: Skeletal & Muscular


HOMEOSTASIS
 All
the systems of the body work
together to maintain homeostasis.
 Homeostasis
is the process by
which an organism’s internal
environment is kept stable in spite of
changes in the external
environment.
MAINTAINING HOMEOSTASIS
 When
you are too warm, you sweat.
Sweating helps to cool your body.
 When
you are cold, you shiver.
Shivering occurs when your muscles
rapidly contract and relax. This
action produces heat that helps keep
you warm.
HOW DOES OUR
BODY WORK
TOGETHER TO
CIRCULATE BLOOD?
CIRCULATORY
SYSTEM
The HEART
(Organ)
HEART
TISSUES
HEART
CELLS
Organelles
REPRODUCTIVE
SYSTEM
AND
HUMAN GROWTH AND
DEVELOPMENT
FUNCTION OF REPRODUCTIVE SYSTEM
•
•
•
•
•
To ensure survival of the species
To produce egg and sperm cells
To transport and sustain these cells
To nurture the developing offspring
To produce hormones
 Other
systems strive to maintain a
state of homeostasis.
The Female Reproductive System
In females all the reproductive organs are found inside
the body
Ovary - the primary female reproductive organ that
produces eggs.
Fallopian Tubes - eggs travel through these to reach the
womb.
Uterus- a hollow, muscular organ in which the fertilized egg
develops
Notes: Females are born with all the eggs they will
need – females do not produce more eggs in
adolescence. The ovaries (along with producing eggs)
produce the female hormones estrogen and
progesterone which trigger the development of female
characteristics – broadening of the hips, development
of breasts, body hair, menstruation, etc.
THE MALE REPRODUCTIVE SYSTEM
In males some of the reproductive organs are
inside the body and some are external.
 Testes - the primary male reproductive organ that
produces sperm.


Notes: At puberty, males begin producing
sperm and they will continue to do this all
their life. The testes (along with producing
sperm) produce the male hormone
Testosterone which triggers the development
of male characteristics – facial and body hair,
muscle development, deepening of the voice,
spermatogenesis, etc.
REPRODUCTIVE SYSTEM DISORDERS
Infertility - not being able to conceive (have a
child) after a year of trying.
 Prostate Cancer - a disease in which cancer
cells grow in the prostate. The prostate is a gland
that surrounds the urethra, the tube that carries
urine out of the body. The prostate is only found
in men.
 Ovarian cancer - a disease in which cancer cells
grow in the ovaries. The ovaries are a pair of
organs in the female pelvis that produce eggs and
female hormones.

REPRODUCTIVE SYSTEM –
GROWTH AND DEVELOPMENT
Stages of Growth and Development :
a.
Zygote
b. Embryo
c.
Fetus
d. Infancy
e.
Childhood
f.
Adolescence
g.
Adulthood
3 STAGES OF DEVELOPMENT BEFORE BIRTH
(TAKES 9 MONTHS)
Zygote
 Single celled, fertilized egg
 Embryo
 From 2 cell stage to 8th week of pregnancy.
 Amniotic sac and placenta develop.
 Heart beats in rhythm, eyes & ears begin to
form.
 Heart develops chambers at about 8th
week.
 Fetus
 From 9th week of pregnancy to birth.
 Majority of development occurs during
this stage.

ZYGOTE AND EMBRYO
Zygote
Embryo
•A zygote is a fertilized egg.
•It is no larger than a
period at the end of a
sentence.
•The fertilized egg is
known as a zygote only
until the 4th day; after that
it is known as an embryo.
•An embryo is a developing
human.
•A zygote becomes an
embryo from about the 4th
day of fertilization until
about the 8th week.
•Eyes and ears begin to
form and the heart beats in
a regular rhythm.
FETUS
FROM ABOUT THE NINTH WEEK OF DEVELOPMENT
UNTIL BIRTH, THE DEVELOPING HUMAN IS KNOWN
AS A FETUS.
INFANCY




Includes the first two years of life.
The highest physical growth rate
occurs in this stage. (– the baby
grows rapidly in size, mental and
muscular skills begin to develop.)
The nervous and muscular systems
become coordinated.
By the end of two years a child can
understand directions, feed
themselves, walk, speak some words
and play with toys.
CHILDHOOD
 Occurs
from about 2-13 years of age.
 Children become taller and heavier, and
more coordinated.
 Children become more curious.
 Language skills improve rapidly.
 Mental abilities increase, memory is
strengthened, muscular, language and
learning skills develop.
ADOLESCENCE / PUBERTY
 The
stage of development which children
become adults physically and mentally.
 Occurs between the ages of 13-20
 Puberty, the stage of development which
allows the body to be able to reproduce,
occurs during these years.
 Menstruation starts in females and males
begin to produce sperm.
 Children in this stage go through a rapid
growth spurt and develop male and
female characteristics.
ADULTHOOD








From 20- Death.
Body systems are mature and full height and weight
have been reached.
The mental and emotional growth of adolescence
continues after puberty ends.
It is difficult to give an exact age of when adulthood
begins since adults, like adolescents, continue to learn
new things.
After about age 30, the process known as aging begins.
Between the ages of about 40 and 60 females go
through menopause when they are no longer able to
reproduce.
Aging includes the skin becoming wrinkled, muscle
strength decreases, eyes may lose their ability to focus
on close objects and hair may lose its coloring.
Older adults have learned a lot from their
experiences, therefore tend to have a great deal of
wisdom.
DISORDER PROJECT PRESENTATIONS
 FOR






EACH PRESENTATION:
What is the disorder being presented?
Who is presenting? (ALL NAMES)
What are the positives of their
presentation?
What are the negatives of their
presentation?
Write three things you learned about this
disorder.
Rate the presentation from (1-5) 5 being the
best what would you rate their presentation
and why?
VIDEO CLIP
 How
Your Body Changes as You Grow 2 min.
WARM UP
On
a piece of paper.
Draw
an outline of a body.
Like this picture------------
Then
fill in any organs, organ
systems, or body parts you
know. Turn in tray.
THE RESPIRATORY SYSTEM
FUNCTION OF THE RESPIRATORY SYSTEM
Provides oxygen to the body and
eliminates carbon dioxide and
excess water.
Breathing: the movement of air
into & out of the lungs.
Respiration: Chemical reaction
involving oxygen and glucose that
results in the release of energy of
fuel various cellular processes.
FUN FACTS:
 Body uses only 5% of the oxygen
you inhale with each breathe.
 Oxygen is carried throughout the
body via circulatory system
(arteries, veins, and capillaries).

STRUCTURE
Functions of the Organs in the Respiratory System
nose / nasal
cavity
Lined with mucus to trap foreign particles It is warm,
moist, & filters air as it is inhaled
pharynx (throat)
larynx
passageway for air, leads to trachea
the voice box, where vocal chords are located
trachea
(windpipe)
keeps the windpipe "open"
trachea is lined with mucus and fine hairs called cilia
which filter and moisten the air as it enters the
windpipe and before it reaches the lungs
bronchi
two branches at the end of the trachea, each lead to a
lung. Divides into smaller and smaller tubes inside the
lungs
bronchioles
a network of smaller branches leading from the bronchi
into the lung tissue & ultimately to air sacs
alveoli
Diaphragm
LUNGS
Tiny hollow sacs of specialized lung tissue where oxygen
is exchanged for carbon dioxide. Ex There are 300
million in the average adults lung for larger oxygen
intake.
Dome shaped muscle located at the base of the lungs
Located on both sides of the heart. Elastic tissue that expands and
contracts as you inhale and exhale.
PATHWAY OF OXYGEN

Body breathes in the air which is pulled through the
nose or mouth and down through the trachea.

The trachea is a pipe shaped by rings of cartilage.

It divides into two tubes called bronchi.

Bronchi carry air into each lung.
PATHWAY OF OXYGEN




Inside the lung, the tubes divide into smaller and
smaller tubes called bronchioles.
At the end of each of these tubes are small air
sacs called alveoli.
Capillaries, which are small blood vessels with
thin walls, are wrapped around these alveoli.
Capillary walls are so thin and close to each
other that the air easily diffuses through.
 The
1.
2.
3.
4.
5.
Gas Exchange Process
Carbon dioxide/Oxygen rich blood flows
into capillaries surrounding the alveoli.
Oxygen moves from the alveoli into the
capillaries surrounding the alveoli.
At the same time, Carbon dioxide moves
from the capillaries into the alveoli
replacing the Oxygen.
The Oxygen rich blood is then carried
through the arteries back to the heart.
The Carbon dioxide is then expelled from
the lungs as the lungs deflate.
Breathing


Inhalation
 Rib muscles contract lifting the chest wall up and out.
(Volume of Lungs Increase)
 Diaphragm contracts & moves downward increasing the
size of the chest cavity & decreasing the pressure within
the cavity.
 The pressure of air is now higher than you chest forcing
air into your chest cavity.
 Ex: Air being sucked into a vacuum cleaner.
Exhalation
 Rib muscles relax lowering the chest wall. (Volume of
Lungs Decrease)
 Diaphragm relaxes & moves upward forcing the lungs to
flatten & carbon dioxide to be forced out of the lungs.
 Ex: Squeezing Ketchup out of a the opening on a bottle
Speaking

Larynx: voice box
 Vocal cords: folds of
connective tissue that stretch
across the opening of the
larynx.
 Muscles make the vocal
cords contract narrowing
the opening.
 Air rushes through the
opening.
 This vibration creates a
sound, your voice. Air
moving over vocal cord
causes the vibration =
producing sound.
RESPIRATORY SYSTEM DISORDERS




Bronchitis - an inflammation of the bronchial
passages within the lungs which narrow and then
become clogged with mucus. Can be caused by
irritants, such as cigarette smoke, air pollution, or
infections
Cystic fibrosis – a genetic disorder that causes a
thick buildup of mucus in the lungs and digestive
system
Asthma - a disorder in which there are periodic
episodes of contractions of bronchial smooth muscle,
which restricts air movement. Many cases of asthma
result from allergic reactions
Lung cancer - Lung cancer is the most common
cause of cancer death in males and females in the
United States, and almost all cases occur in smokers.
Uncontrolled growth of lung cells that produce tumors
that prevent the lung from operating effectively.
SMOKING!!!!!
https://www.youtube.com/watch?v=6wsXe
e9SZ04
DISCUSSION QUESTIONS

What types of things can affect breathing or damage
lungs?
Smoking, second hand smoking, asthma, pollutants, chemicals,
inhalants, allergens

Think back to our atmosphere unit – Does altitude or
elevation affect your breathing?
Yes, the higher you go up, the hard it is to breath because of
reduced air pressure

Respiration at High Elevations video clip – United
Streaming: 7 min.48 sec.
DISCUSSION QUESTIONS



What two gases are exchanged during breathing?
Oxygen and carbon dioxide
What are the two functions of the respiratory system?
Provides oxygen to the body and eliminates carbon
dioxide and excess water.
Through what structures does air pass to get to the
lungs?
Nose – Pharynx – Trachea – Bronchi
RESPIRATORY VIDEO LINKS
https://www.youtube.com/wat
ch?v=RPdGQ-A_yM4
https://www.youtube.com/wat
ch?v=hzOSzX_HXE4
https://www.youtube.com/wat
ch?v=AJpur6XUiq4
CIRCULATORY SYSTEM
CIRCULATORY SYSTEM
INTRODUCTION VIDEO

http://kidshealth.org/kid/htbw/CSmovie.html
FUNCTION OF THE CIRCULATORY SYSTEM
It is the body’s delivery and transport system.
Helps transport blood, oxygen, and nutrients
throughout the body.



To get rid of waste the body does not need (CO2)
Can be referred to in science as the cardiovascular
system.
Cardio means “heart”.
 Vascular means “related to blood.”

HEART
The heart, the lungs,
and the blood vessels
work together
to form the circle
part of the
circulatory system.
o The heart is a hollow Muscular
organ responsible for pumping
blood throughout the body.
 Made of Cardiac Muscle.
 4 Different Chambers:
2 on each side and 1 on top and
1 on bottom.
o
PARTS OF THE HEART
Atria – The top 2 chambers. Receives
blood returning to the heart from the
body and lungs.
Ventricles – The 2 bottom chambers.
Pumps the blood out to the body and
lungs
Septum – A thick wall of muscle that
separates the sides of the heart.
HEART VALVES
 Flaps
of tissue located inside the heart
that separates the atrium and ventricle
and directs blood flow.
 Tricuspid
 Pulmonary
 Mitral (Bicuspid)
 Aortic
THE HEART

The right side of the
heart is completely
separated from the left
side by a wall of tissue
called the Septum
Each side has 2
chambers:
Upper Chamber: Atrium
Lower Chamber:

Ventricle
•Heart beat is regulated by a
pacemaker
•Natural pacemaker is a group of
cells located in the right atrium that
monitors the body’s need for oxygen
& adjust the heart rate to meet the
need.
•Artificial pacemaker is an
electrical device implanted in a
patient that regulates the heartbeat.
•Can be affected or disrupted by
microwaves.
THE 2 LOOPS OF THE HEART

Loop 1: Right Pump

Blood travels from the heart to the lungs & then back
to the heart.
 Oxygen poor/Carbon dioxide rich blood flows into
right atrium from the body.
 This blood is then pumped through the tricuspid
valve into the right ventricle.
 The ventricles pump the blood through the
pulmonary valve into the pulmonary artery that
leads to the lungs.
 Pulmonary: means lungs
 There the lungs exchange fresh oxygen for carbon
dioxide.
 The now oxygen rich blood flows from the lungs
into the left side of the heart or the 2nd loop.
LOOP 2: LEFT PUMP

Blood travels from the lungs to the heart & then to the
body.
 Oxygen rich blood flows into left atrium from the
lungs.
 This blood is then pumped through the mitral/bicuspid
valve into the left ventricle.
 The ventricles pump the blood through the aortic valve
into the aorta that leads to the body.
 The contraction of the left ventricle is greater creating
more force as this push is needed to pump the blood
throughout the entire body.
 Throughout the body, blood drops off oxygen to various
cells & picks up carbon dioxide.
 This Oxygen poor/Carbon dioxide rich blood flows back
to the right side of the heart to begin the 2 loops
process all over again.
ARTERIES
Carry blood AWAY from the heart
 Carry oxygen rich blood throughout
the body.
 Heart pumps blood
 Main/Largest artery called the aorta
 Aorta divides and branches
 Coronary Arteries are arteries that
Supply the cells of the heart with oxygen
 Many smaller arteries
 Each region of your body has system of arteries
supplying it with fresh, oxygen-rich blood.
 Tough on the outside
 Smooth on the inside
 Muscular wall helps the heart pump blood

VEINS
Carry blood to the heart
 Carry oxygen poor/carbon dioxide rich blood
throughout the body.
 Receive blood from the capillaries
 Transport waste-rich/ oxygen-poor blood back to the
lungs and heart
 Valves are located inside the veins
 Allow blood to move in one direction
 Contraction of skeletal muscles help to push blood
through veins back to the heart.

WARM UP
COMPLETE
“HEART
DIAGRAMS” ON THE
WORKSHEET YOU WERE
GIVEN.
WE WILL GO OVER IT.
CAPILLARIES
 Very
thin
 Only one cell thick
 Connects arteries & veins
 Releases food and oxygen to the body
 Carbon Dioxide and other wastes are returned
to the bloodstream
PULSES AND BLOOD PRESSURE








Your pulse is created by the expansion & relaxation of the
artery walls.
Arteries can expand or contract to restrict blood flow to an
area.
Example: Exercising blood flow increases to muscles and lung cells.
Example: During digestion blood flow to the digestive system
increases
Blood pressure is the force exerted on the walls of arteries as
blood is pumped through the ventricles of the heart.
Blood pressure decreases the further it travels from the heart.
Inadequate blood pressure can mean not enough oxygen and
nutrients are being delivered to vital organs such as the brain, heart,
etc., preventing these organs from functioning properly and may lead
to temporary or permanent damage.
Measured using a sphygmomanometer or blood pressure cuff.
THE HEART AT WORK


http://www.medtropolis.com/VBody.asp - tour through
the heart
http://www.pbs.org/wgbh/nova/eheart/transplantwave.
html - perform a heart transplant
PARTS OF BLOOD
BLOODMOBILE


http://www2.fi.edu/exhibits/permanent/resources/
heartsongMed.mpg
Can you figure out why some bloodmobiles are
red and some are blue?
BACKGROUND INFORMATION:
All blood is produced in bone marrow, which is
found inside of bones.
 Marrow is full of nutrients and all 4 components
of blood.
 An average of 2.6 million red blood cells are
produced each second by the bone marrow to
replace those worn out and destroyed by the
liver.

RED BLOOD CELLS
These cells carry oxygen, they can be dark red (oxygen
poor) or bright red (oxygen rich).
 Blood is NEVER blue, this is a huge misconception.
 Red blood cells carry hemoglobin (composed mostly of
this), which is an iron containing protein that contains
oxygen.
 They are disc shaped with a pinched center. This
allows it to bend and squeeze through capillaries and
carry oxygen.

http://hes.ucf.k12.pa.us/gclaypo/circdia.htm
l
WHITE BLOOD CELLS
These cells fight infection.
 They are larger in size, but they are fewer in
numbers.
 Produced in Bone Marrow
 The body produces several different types of
white blood cells.
 The body increases production of white blood
cells when they are needed.
 Diseases of white blood cells

Leukemia – cancer of WBC’s
 HIV – virus that attacks specific lymphocytes

PLATELETS
Platelets are cell fragments that help the blood to
clot at a wound site. (Scabs)
 They are shaped somewhat like plates.
 Like the red and white blood cells, platelets are
produced in bone marrow.
 Hemophiliacs lack a sufficient number of
platelets

user.gru.net/clawrence/ vccl/chpt7/plate.htm
PLASMA
Plasma is the fluid/liquid portion of blood.
 It makes up 55% of blood and is a straw (yellow)
colored liquid.
 About 90% of it is made
of water. 10% dissolved materials
such as glucose, fats, vitamins, &
minerals.

United Streaming Video Clip:
Bill Nye - Blood Circulation - 2min.50 sec.
Bill Nye – Blood Transfusions – 2min.9sec.

CIRCULATORY SYSTEM DISORDERS



Atherosclerosis- High fat diets can lead to formation of
fatty plaques lining blood vessels. These fatty areas can
become hard leading to arteriosclerosis, hardening of the
arteries. When blood vessels become less stretchable,
blood pressure rises and can result in heart and kidney
damage and strokes.
Myocardial infarction (MI)- The scientific name for a
“heart attack.” The blockage occurs in one of the arteries
of the heart muscle itself, a coronary artery. Depending
upon how much tissue dies, a victim of an MI may survive
and undergo cardiac rehabilitation, strengthening the
remaining heart muscle, or may die if too much muscle
tissue is destroyed.
Arrhythmia/dysrhythmia- Abnormal heart rates and
rhythms all have special names like ventricular
tachycardia, fibrillation, but generically are termed
arrhythmias or dysrhythmia, meaning “no rhythm” and
“abnormal rhythm.” There are fine distinctions between
the two, but they are often used interchangeably
HOW DO THE SYSTEMS WORK
TOGETHER?
Watch How the
Respiratory and
Circulatory Systems
Work together! (18 min.)
http://users.tpg.com.au/users/amcgann/body/respiratory.html
WARM UP – HUMAN BODY SPOD
QUESTION #2
What
4 components make up blood?
What are RBC’s? What do they do?
What are WBC’s? What do we do?
What is Plasma? What makes up
plasma?
What are platelets? What can we do?
What color do you think blood is and
why? Prove your theory.
WARM UP: MAKE SURE THESE ARE DONE AND YOU ARE READY
TO TALK ABOUT IT. ALSO, COME GET YOUR ½ SHEET FROM WAS
FROM YESTERDAY AND MAKE SURE IT IS DONE.
 With your data and pictograph, create a line graph
showing what happened during the lab.
Compare and Contrast the # of breaths you took when
you were resting vs when you were participating in
physical activity.
 Describe what happened over the course of the lab.
What happened as you increased your physical
activity?
 Analyze your data, what you said in the question
above, & what you saw. Then describe what breathing
rate is & why it increased as the lab went on.
 Now your turn!! Create a scenario or lab that would
show the relationship between the amount of oxygen
your body needs to your breathing rate.

HARVARD STEP TEST DISCUSSION/ANALYSIS QUESTIONS
ON SEPARATE SHEET OF PAPER
 Compare and contrast data from your breathing rate and
heart rate. Describe the pattern you saw.
 Explain the difference between the rates when you were
resting vs when you were walking/stepping. Why were they
different?
 Analyze the data and conclusions about the lab you
collected and then describe to me what heart rate is and
breathing rate. What do they measure? What is their
relationship to each other and to physical activity?
 Overall, in your own words summarize what occurred
during the lab and then explain to me why that happened?
 Lastly, think about the last two labs and then draw one
interconnecting picture that explains/incorporates
breathing rate, heart rate, breathing, oxygen, resting, and
physical activity.
DIGESTIVE SYSTEM
FUNCTIONS OF THE DIGESTIVE
SYSTEM
- The Digestive Process Begins




The digestive system has
three main functions.
It breaks down food into
molecules the body can
use.
The molecules are
absorbed into the blood
and carried throughout
the body.
Wastes are eliminated
from the body.
DIGESTION




The process by which your body breaks down food into
small nutrient molecules is called digestion.
There are two kinds of digestion—mechanical and
chemical.
Mechanical digestion – food is physically broken down
into smaller pieces.
Chemical digestion, chemicals produced by the body
break foods into their smaller chemical building blocks.
VIDEO CLIP

Video Clip from Kids Health
GRAPHIC ORGANIZER
In the mouth, the teeth break food into smaller pieces and saliva
begins to break down starches.
Esophagus pushes food from mouth to stomach.
In the stomach, food is churned and mixed with digestive juices
that break down protein.
In the small intestine, almost all chemical digestion and absorption
occurs.
Large intestine absorbs water and eliminates waste.
THE MOUTH
- The Digestive Process Begins
Both mechanical and chemical digestion begin
in the mouth.
 Saliva- The fluid released when the mouth
waters that plays an important role in both
mechanical and chemical digestion

THE ESOPHAGUS

After leaving the mouth, food goes into the esophagus – a
muscular tube that connects the mouth to the stomach.
The esophagus is lined with mucus, a thick, slippery
substance produced by the body.
 Esophagus- A muscular tube that connects the mouth to
the stomach


After food enters the esophagus, contractions of smooth
muscles push the food toward the stomach. These
involuntary waves of muscle contraction are called
peristalsis. These muscular waves keep food moving in
one direction.
- The Digestive Process Begins
THE STOMACH

Most mechanical digestion and some chemical
digestion occur in the stomach.
DIGESTION IN THE STOMACH
Mechanical Digestion in the Stomach
 The physical actions, such as chewing, that help break
down food during digestion. Another example of
mechanical digestion occurs as the smooth muscle
contract to produce a churning motion.
Chemical Digestion in the Stomach
 Digestive juice contains the enzyme pepsin. Pepsin
chemically digests the proteins in your food, breaking
them down into short chains of amino acids.

Digestive juice also contains hydrochloric acid, a very
strong acid.
WARM UP
Pull
out notes sheet from
yesterday.
Use textbook (pg 61) to
complete the digestive
system diagram on
worksheet.
EPIGLOTTIS
As you swallow, a flap of
Tissue called the epiglottis,
Which seals off your windpipe, preventing the food
from entering your lungs.

- Final Digestion and Absorption
THE SMALL INTESTINE

The small intestine is the part of the digestive system
where most chemical digestion and absorption of
nutrients take place.
LIVER AND GALLBLADDER
The role of the liver in
the digestive system is to
produce bile.


Bile is a substance that breaks up fat particles. Bile
flows from the liver into the gallbladder, the organ
that stores bile. After you eat, bile passes through a
tube from the gallbladder into the small intestine.
THE PANCREAS
As part of the digestive system, the pancreas
produces enzymes that flow into the small intestine
and help break down starches, proteins, and fats.
 Fiber isn’t broken down in the digestive system.
Instead fiber turns into a thick liquid material to
help push material forward.

- Final Digestion and Absorption
THE SMALL INTESTINE
Tiny finger-shaped projections called villi line the
inside of the small intestine. Villi absorb nutrient
molecules.
 The molecules pass from the villi into blood vessels.

THE LARGE INTESTINE - COLON



As the material moves through the large intestine, water
is absorbed into the bloodstream. The remaining material
is readied for elimination from the body.
The large intestine contains bacteria that feed on the
material passing through. They are helpful because they
make certain vitamins, including vitamin K.
The large intestine ends in a short tube called the
rectum. Here, waste material is compressed into a solid
form. This waste material is eliminated from the body
through the anus, a muscular opening at the end of the
rectum.
METABOLISM:
-THE RATE THAT YOUR BODY TURNS FOOD INTO
ENERGY.

People can have a slow or fast metabolism.
Each person's caloric intake varies, but on
average you can assume that each person
needs 2,000 calories per day. By
interpreting a nutritional food label, each
person can keep up with the number of
calories they eat each day along with the
vitamins and nutrients they consume.
DIGESTIVE SYSTEM DISORDERS
Gastroesophageal Reflux Disease (GERD) Severe “heartburn” - Weakness of the valve between
the esophagus and stomach may allow stomach acid
to reflux (regurgitate, backup) into the esophagus
and irritate and inflame the lining.
 Crohn’s Disease - a chronic inflammatory disease
primarily of the bowel. Typical symptoms are
abdominal pain, weight loss, diarrhea.
 Cirrhosis – The name means “orange-yellow” in
Greek. A degenerative disease of the liver that often
develops in chronic alcoholics, but can have other
causes. The name refers to the gross appearance of
the organ.

THE EXCRETORY SYSTEM
How Our Body Eliminates Cellular Wastes
EXCRETORY SYSTEM FUNCTIONS
Excretory System – removes excess water, H2O,
urea, carbon dioxide, CO2, and other wastes
from our blood.
http://kidshealth.org/kid/htbw/USmovie.html



Kidneys – filter out excess water and urea
Lungs – filter out carbon dioxide, CO2, from the
blood.
Skin – excretes water, as sweat, which contains
some trace chemical wastes, including urea.
SKIN
 The
skin gives off a waste product
called sweat to help the body cool itself.
 If your body loses too much water you
can become dehydrated.
 The skin can become damaged from
burns, cuts and over-exposure to the
sun.
 You are at a greater risk for sunburn or
direct sunrays during the hours of
11am-3pm.
EXCRETORY CON’T

Excretion maintains homeostasis by keeping the body’s
internal environment stable and free of harmful levels of
chemicals.
 Kidney - Filter blood and help to maintain homeostasis
by regulating the amount of water in your body.
 Ureter – two narrow tubes that urine flows from the
kidneys to the bladder.
 Bladder and Urethra – Urine leaves bladder and
released through the urethra.
 Lungs – carbon dioxide is released and excess water
 Skin – Sweat glands in the skin help release urea and
water
 Liver – like a recyling factory. Breaks down waste before
they are excreted. Urea is produced in liver. Liver also
converts old red blood cells into bile.
EXCRETORY SYSTEM DISORDERS
Kidney Stones - These are smaller sized
deposits of calcium in the kidney. The stones can
also increase or go down to the urinary tract
causing extreme pain. The stone may also get
infected causing further complications
 Bladder Cancer - When there is uncontrolled
growth of cells present in bladder, it is known as
bladder cancer. The end result is a tumor in the
bladder.

EXCRETORY SYSTEM REVIEW

What organs help to remove waste products from
our bodies?


What do the kidneys do?


Lungs, skin, kidneys
Filter the blood to remove waste products
What would happen if the kidneys did not filter
the blood?

The waste products would build up and poison the
blood
EXCRETORY VIDEO
•
•
•
•
•
•
An Introduction to the Excretory System [02:14]
The Lungs [01:27]
The Liver [01:51]
The Skin [02:00]
Summary of the Excretory System [00:51]
Video Questions