Transcript Human Body Systems






Cells are the basic building blocks of all living
organisms.
A group of similar cells that work together to
perform a function is called tissues.
A group of different tissues that work together
to perform a function is an organ.
Groups of organs working together form organ
systems.
All organ systems work together to make a
fully functioning organism—YOU!
Warm, dilute
Warm, dilute
ocean waters
ocean waters
Unicellular
• All cells in direct contact with
environment
• All cells can easily get nutrients
in & waste out by diffusion
Multicellular
• Internal cells not in direct contact
with environment
• Internal cells can’t get nutrients in
& waste out
• Need organ systems

Had to evolve organ
systems for:


getting materials in &
around
 digestive system
 respiratory system
 circulatory system
removing wastes
 respiratory system
 excretory system


Digestion is the
process of breaking
down food into
molecules that the
body can use
The digestive system
takes in food, breaks it
down, and gets rid of
undigested molecules
and waste.




Mouth—begins digestion by taking in food
Teeth—mechanically breaks down food into
pieces
Tongue—tastes the food (makes sure it is
safe); moves the food around and mixes it
with saliva
Salivary Glands—produce saliva which
contains Salivary amylase (breaks down
complex carbohydrates)



Epiglottis—a flap of tissue that moves over
the opening of the trachea, so that food does
not enter the trachea
Pharynx—the passage from the mouth to
the larynx (produces vocal sounds) and
esophagus
Esophagus—a long, straight tube that
connects the pharynx and stomach



The stomach is a
muscular, saclike organ.
Function: secretes
gastric juice
(combination of HCl acid
and Pepsin); churns the
food and coats it,
beginning digestion.
Pepsin—a stomach
enzyme that breaks
down proteins




Function: secretes bile,
converts extra sugars to
glycogen for storage,
stores fat-soluble vitamins
and iron and detoxifies
poisons.
Bile—a greenish fluid that
breaks fat globules into
tiny fat droplets, promotes
absorption of vitamins
Glycogen—a complex
carbohydrate that stores
glucose
Gall Bladder—Stores bile
Liver, Gall Bladder, and Bile Duct



Function: Secretes
several digestive
enzymes into the small
intestine, secretes
insulin to regulate blood
sugar, secretes
pancreatic fluid
Insulin—a hormone that
regulates the release of
glucose into the blood
Pancreatic Fluid—raises
the pH of stomach acid,
contains many digestive
enzymes


Function—the majority
of food digestion occurs
in the duodenum (the
first part of the small
intestine), the
absorption of
nutrients occurs in the
jejunum and ileum
Villi—small projections
from the cells in the
lining of the small
intestine which absorb
the nutrients
Villi of
Small
Intestine



Function—mineral ions
and water are absorbed
from waste material(no
digestion occurs here).
Also in the large
intestine are microbes
which synthesize
vitamin K and several B
vitamins, which your
body cannot easily get
from food
Appendix—no function
in humans. (called
caecum in pigs)
Rectum—stores solid wastes
Anus—eliminates wastes

The heart, blood
vessels, and blood
make up the
cardiovascular system




Oxygen from the lungs is moved
throughout the body by the
blood
Nutrients from digested foods
are absorbed by the blood and
carried to all the body’s cells
Cellular waste products are
moved by blood to the urinary
system
Hormones, substances that
help regulate body functions,
are carried by the bloodstream


Organ
 heart
Tissues & cells
 Blood vessels
 arteries
 veins
 capillaries
 Blood
 red blood cells
 plasma (liquid)
Chambers and Blood Vessels of the Heart

4-Chambered heart

atria (atrium)
thin wall
 collection chamber
 receive blood


ventricles
thick wall pump
 pump blood out

left
atrium
right
atrium
right
ventricle
left
ventricle
Not everyone has a 4-chambered heart
fish
2 chamber
V
amphibian
3 chamber
reptiles
3 chamber
A
A
V
A
A
V
A
V
birds & mammals
4 chamber
A
V
A
V

4 valves in the heart



flaps of tissue
prevent backflow of blood
SL
Heart sounds




closing of valves
“Lub”

force blood against closed AV valves

“Dub”

force of blood against semilunar valves

Heart murmur
leaking valve causes hissing sound
blood squirts backward through valve
AV
AV
arteries
veins
artery
venules
arterioles
arterioles
capillaries
venules
veins

Arteries


blood flows away from heart
thicker walls


provide strength
for high pressure
pumping of blood
elastic & stretchable

Blood flows
toward heart
Veins


blood returns back to heart
thinner-walled
Open valve
blood travels back to heart
at low speed & pressure
 why low pressure?



blood flows because muscles
contract when we move


far from heart
Closed valve
squeeze blood through veins
valves in large veins

in larger veins one-way valves
allow blood to flow only toward heart

Capillaries


very thin walls
allows diffusion of
materials across
capillary

O2, CO2, H2O,
food, waste
waste
body cell
CO2
O2
food

Blood is a tissue of fluid & cells

plasma
liquid part of blood
 dissolved salts, sugars, proteins, and more


cells

red blood cells (RBC)


white blood cells (WBC)


transport O2 in hemoglobin
defense & immunity
platelets

blood clotting
ribs, vertebrae,
breastbone & pelvis
 Stem cells
“parent” cells white blood cells
in bone
marrow
 develop into all
the different
red blood
types of blood
cells
cells

 red blood cells
 white blood cells
white blood
cells

Small round cells




produced in bone marrow
5 liters of blood in body
5-6 million RBC in drop of human blood
last 3-4 months (120 days)
 filtered out by liver

~3 million RBC destroyed each second

Protein which carries O2

250,000 hemoglobin proteins in one red blood cell
O2
O2
O2
O2
Why do we need a
respiratory system?
1. To bring Oxygen in. Oxygen
is needed for cells to break
down glucose to make ATP.
2. To take out Carbon Dioxide.
Carbon Dioxide is a waste
product of cellular
respiration and must be
taken out of the body.
What is Respiration?
The exchange of gases
from the environment to
the body.
Functions of the Major
Organs:
Nose and Mouth—brings
in air
Sinus Cavity—moistens,
cleans and warms the air
before it goes down to the
lungs
Throat—contains Larynx
(voice box) for speech




Lungs—Function: Major
organ of respiratory
system; gas exchange
Trachea—Function: rigid
tube that transports air to
lungs
Bronchus &
Bronchioles—Function:
branches off of trachea,
delivers air to alveoli
Diaphragm—Function:
muscle that expands and
contracts the lungs



Bronchus—branches
off of the trachea
Bronchioles—smaller
branches of the
Bronchus
Bronchioles end in
Alveoli—’little air sacs’



Alveoli—little air
sacs where gas
exchange occurs.
expand when air is
taken in, contract as
air is exhaled.
Closely associated
with capillaries
from the pulmonary
veins and arteries.

Structure
spongy texture
high surface area
 more absorption of O2


moist lining


mucus traps dust,
pollen, particles
covered by cilia
hair-like extensions of cells
 move mucus upward to
clear out lungs


Inhale



O2 passes from alveoli
to blood
by diffusion
Exhale


CO2 passes from blood
to alveoli
by diffusion
capillaries
(circulatory system)

Gases move by diffusion from high to low
concentration
capillaries are thin-walled tubes of circulatory system
 alveoli are thin-walled sacs of respiratory system
capillaries in lungs
capillaries in muscle

O2
O2
O2
O2
CO2
CO2
CO2
CO2
blood
lungs
blood
body

Diaphragm moves down & expands chest cavity
pulls air into lungs
inhale
exhale
What is the excretory
system?
The organ system that
removes wastes
produced during
metabolic reactions

Animal cells move material across the cell
membrane by diffusion
nutrients
 nutrients in
sugar
 from digestive system
CO2
 fuels for energy in
urea
 from digestive system
O2
 oxygen in from respiratory system
nutrients
sugar
 waste out
O2
 CO2, urea from cells

to respiratory system, to excretory system


Digesting protein makes poison
Nitrogen waste= ammonia=poison
When the
Amino
group is
removed, it
makes
ammonia,
NH3
In land
animals,
the NH3 is
converted
to urea
When the other
functional groups are
removed, they are lost
as carbon dioxide and
water
Nitrogen waste
 The kind of nitrogen
waste you make
depends on where
you live



Freshwater animals
 Make ammonia
Land animals (not
egg layers)
 Make urea
Land egg layer
 Make uric acid

Freshwater animals

If you have a lot of water you can dilute the waste
before it poisons you
 excrete ammonia through gills and as urine

Land animals


need to save H2O
evolved less poisonous waste product


urea
excrete urea & H2O as urine

Egg-laying land animals



no place to get rid of waste while in egg
needs waste that doesn’t dissolve in water inside egg
 uric acid
 stays a powder inside egg
birds, reptiles, insects

Mammals have a pair of
bean-shaped kidneys

supplied with blood by a renal artery and a renal
vein
Kidney—filters
urea out of blood;
makes urine
Vena cava
Aorta
Renal
Artery
Kidney
Ureter—delivers urine to
urinary bladder
Urinary bladder—stores urine
Urethra—delivers urine out of
body
Renal Vein
Vena cava-carries filtered
blood back to heart
Aorta—brings blood to
kidney to be filtered
Renal artery-a branch off
of the aorta which carries
blood to the kidney
Renal vein—blood vessel
coming from the kidney to
the vena cava
Cortex—outer area
of the kidney;
contains numerous
blood vessels
Medulla—inner area
of the kidney;
contains the
structures of the
nephron that
maintain salt and
water balance
Ureter—collects urine and
transports it to bladder
Nephron—the filtering
structures of the kidney;
filters nitrogen waste out
of the blood
Renal Artery—brings
blood to the kidney to
be filtered
Renal Vein—takes
filtered blood back to
the heart
Reproductive
Systems
2006-2007


Humans reproduce sexually by internal
fertilization.
The roles of the male reproductive system
are to produce sperm and to deliver sperm
to the female reproductive system.
*Seminal vesicle—
helps make semen,
nutrient-rich liquid
that helps sperm
cells survive
Urethra—delivers urine
and sperm outside
body
Scrotum—sac that holds
and protects testis
Penis—organ that
delivers sperm into
female reproductive tract
Urinary Bladder—
stores urine
Prostate and
Bulbourethral
Glands-*
Erectile
tissue—fills
with blood
Delivers sperm
to urethra
where sperm cells
mature
Where sperm cells are made



Testes have hundreds
of compartments
packed with tightly
coiled tubes called
seminiferous tubules.
Sperm cells are
produced by meiosis in
the seminiferous
tubules.
In addition, the testes
produce testosterone.
Testosterone—a
hormone that stimulates
sperm production and the
growth of facial hair and
other male features.



Sperm production starts
during puberty and
continues throughout
adulthood.
Sperm form in testis, then
travel to epididymis,
where they mature.
From there, they move to
the vas deferens, which
carries sperm to the
urethra.
As sperm move into the
urethra, they mix with fluids
secreted by the seminal
vesicles, the prostate gland,
and the bulbourethral
glands.


The tail of a sperm cell is a
powerful flagellum that whips back
and forth, allowing it to move.
During fertilization, only the head of
the sperm enters an egg.
A mature sperm cell
has a head with very
little cytoplasm, a
midpiece (with many
mitochondria), and a
long tail.
Enzymes produced at
the tip of the head help
the sperm cell
penetrate the egg
during fertilization.

Ovaries


Uterus & Endometrium


tubes for eggs to travel from ovaries to uterus
Cervix


nurtures fetus; Endometrium is the lining which builds
up each month
Fallopian tubes (oviduct)


produces eggs & hormones
opening to uterus, dilates 10 cm for birthing baby
Vagina

birth canal for birthing baby
Corpus luteum—a
temporary endocrine
gland that produces
progesterone to
maintain the uterus if
pregnancy occurs
Follicle—the
supporting cells
which nurture the
egg as it matures




The ovaries produce egg cells. They also secrete
estrogen and progesterone, the female sex
hormones.
The female reproductive system produces one
viable egg per month. When an egg cell matures, it is
called an ovum.
After the ovum is released from an ovary, cilia sweep
the ovum into a fallopian tube.
This tube moves the ovum from an ovary to the
uterus. If sperm are present in the fallopian tube
during this time, the ovum may become fertilized.