Transcript Human Physiology Notes

Human Physiology Notes
• Each system is composed of
cells, tissues, organs, and
organ systems.
• Cells: basic unit of structure
and function in living things
2 Types of Cells are:
• Prokaryotes=have no nucleus
nor organelles
ex. Bacteria
• Eukaryotes= have nucleus &
organelles
ex. All other living organisms
Tissues: a group of cells used to
perform a single function
1. Epithelial: glands and tissues
that cover internal and external
surfaces
2. Connective: provides support
for the body and its parts
3. Nervous: transmits nerve
impulses(messages) throughout
the body
4. Muscular: enables the body to
move.
• Organs: a group of different
types of tissues that work
together to perform a single
function.
• Organ system: a group of
organs that perform closely
related functions.
Digestive System
FUNCTION: help convert food
into simpler molecules that
can be absorbed and used by
the cells of the body.
2 Types of changes occur
• Physical Changes: break down
food into smaller parts
• Chemical Changes: enzymes
used to break down food.
• Mouth: responsible
for mechanical
digestion (breakdown)
of food
• Teeth: Chews food
into smaller parts
•Tongue: Mixes food with saliva
(amylase)that breaks down starch
(amylose)=by HYDROLYSIS
• Esophagus: moves
food to stomach by
peristalsis, muscular
contractions,
• Stomach: Beginning
of chemical digestion;
mixes food with more
enzymes & HCl and
churns (grinds) food.
• Small
intestine:
contains
finger-like
projections
called
intestinal
villi that
absorbs
nutrients
from food
• Intestinal villi: Folded to increase
surface area in intestine for more
absorption of food
• Large Intestine:
Removes water
from undigested
• Rectum: Storage
of undigested
food
• Anus: posterior
opening where
undigested food
is excreted.
Additional Organs Needed:
• Liver: makes bile (breaks down
fat); storage of glycogen
(blood sugar = glucose)
• Gallbladder: stores bile made
by the liver & is used to break
down fats (lipids)
• Pancreas: secretes insulin
(lower glucose levels-by
condensation) & glucagon (to
raise glucose levels-by
hydrolysis)
Respiratory System:
FUNCTION: exchanging of
oxygen & carbon dioxide
between the blood, air &
tissues. (cells)
• Nose: has hairs that blocks or
traps dust and unwanted
objects
• Nasal Cavity: warms airs and
acids and adds moisture as it
enters.
• Epiglottis: flap
that closes over
trachea during
swallowing to
keep food out of
lungs
• Trachea: tube that carries air
from the nasal chamber to
the bronchi.
• Bronchi: short tubes that
carries air from the trachea
to the lungs
• Lungs: main organ of
respiratory system; contains
tiny air sacs and capillaries
where oxygen moves into blood
and carbon dioxide moves out
• Alveoli: Tiny air sacs in the
lungs: site of gas exchange by
diffusion
Human Nervous System
FUNCTION: controls and coordinates
functions throughout the body;
responds to internal and external
stimuli. Transmits biochemical signals
(neurotransmitters) through the
nerve cells (neurons); used to
transmit impulses
• Main part: Neuron (nerve cell);
Nervous system is broken down
into two parts:
1. Central nervous System (CNS):
brain and the spinal cord
2. Peripheral Nervous System
(PNS): All the nerves in the
nerves in the body.
• The Nervous System also
controls your senses: (vision,
hearing, smell, taste and touch)
• Cerebrum (voluntary):
Controls thought, reason,
senses, personality
• Cerebellum (involuntary):
maintains balance; makes
smooth movement
• Medulla (involuntary): controls
heartbeat, breathing, blood
pressure
• Reflex-Arc Pathwaytransmission of impulses;
Receptor------sensory Neuron--motor Neuron-------Effector.
Endocrine System
FUNCTION: made up of glands
that release hormones into
the bloodstream: hormones
act as messengers in the body.
• Hormones (chemicals) are
released into the circulatory
system (blood)
• Pituitary: releases hormones that
controls growth; makes hormones
that effect kidney and sex
organs. (master gland).
• Thyroid: makes thyroxine,
controls how fast cells use food
(metabolism)
The main
hormones
produced by the
pituitary are:ACTH �
adrenocorticotropic
hormone
ADH � antidiuretic hormone,
or vasopressin
FSH � folliclestimulating
hormone
GH � growth
hormone
LH � luteinizing
hormone
PRL � prolactin
TSH � thyroidstimulating
hormone
• Parathroid: controls
balance of calcium
• Adrenal Gland: helps the
body in time of stress
(adrenaline)
• Pancreas: controls amount
of sugar (glucose) in blood
• Ovaries:
controls female
traits (estrogen
and
progesterone)
• Testes: controls
male traits
(testosterone)
Excretory System
FUNCTION: maintains
homeostasis by removing
waste products from the
blood, maintains blood pH,
water content , etc
• Kidneys: filters blood and
removes waste (urea); the
chief is ammonia NH3
• Nephron: is the functional
subunit of kidney
• Adrenal Gland: sits on top of
the kidneys (produces
adrenaline)
• Ureter: tube leading from the
kidney to the urinary bladder
• Urinary Bladder: sac that
holds the urine.
• Urethra: opening at the
posterior end of bladder;
where urine is excreted
Circulatory System
FUNCTION: transports
oxygen, nutrients and waste
throughout the body;
Includes: heart, blood, and
blood vessels
• Heart: muscular structure
that pumps the blood.
• Blood vessels: includes
arteries (blood away from the
heart), veins (blood towards
the heart), capillaries
(smallest vessels).
• Blood: made up of blood cells
made in the bone marrow.
Flow of blood throughout the
heart
• Right Atrium: blood enters
heart from the vena cava (vein)
• Right Ventricle: blood enters
here from the right atrium
through biscupid valve and goes
to lungs by Pulmonary Artery.
• Lungs: CO2 is
removed O2 is
picked up
• Pulmonary Vein:
brings
oxygenated blood
back to the heart
from the lungs
• Left Atrium: oxygenated
blood enters here
• Left Ventricle: oxygenated
blood moves to the Aorta
(artery)
• Aorta: large artery; takes
oxygenated blood to all parts
of the body
Overview of blood flow: RA---RV--Lungs----LA------LV----Aorta
Parts of Blood :
2 Types of Blood cells:
• (RBC): carry oxygen
(hemoglobin); if low
person feels tired
• WBC: fight infections
in the body; also known
as leukocytes,
phagocytes,
macrophages.
• Lymphocytes: special WBCs that
produce antibodies
Additional Blood
Components:
• Platelets: responsible for
blood clotting (contains
Factor VIII protein and
associated with
hemophilia)
• Plasma: watery portion of
the blood
Lymphatic System
FUNCTION: Immune System,
filters out disease causing
problems
Main part: Lymph Nodes
Skeletal System
FUNCTION: supports the body,
protects internal organs,
provides for movements,
stores minerals (calcium etc);
and site of blood cell
formation:
• 206 bones in the body
• Axial Skeleton: supports head,
back, & chest.
• Appendicular Skeleton: limb bones
(arms & legs)
• Joints: immovable (skull), ball
and socket (shoulder), Hinge
(knee/elbow), pivot
(neck/forearm)
Saddle/Gliding (wrist/ankle)
• Ligaments: connects bone to
bone; Tendons: connects bone
to muscle
Muscular System
3Types Of Muscle
• skeletal: movement of bones
• smooth; involuntary movement
of organs
• Cardiac: found only in the
heart
Integumentary System:
FUNCTION: serves as a barrier
against infection and injury; helps
maintain homeostasis, removes
waste products from the body and
protects against UV radiation
• Includes : skin, hair, nails, sweat
glands, and oil glands
Reproductive System
FUNCTION: responsible for the
continuity of life, produces
gametes (sperm and egg) by
Meiosis – leads to more variation
• Embryonic development –