Download Structural levels of organization:

Structural levels of organization:
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body has many levels of organization
simplest level is the chemical level (study on your own in ch.2)
Atoms
o Tiny building blocks come together to form
molecules
o come together to form
cells
o smallest unit of living things
o basic structure of all living things
cellular level examined in chapter 3.
tissues
o groups of similar cells with common function
o 4 basic types
o come together to make up…
organs
o complex functions become possible
organ system
o group of organs that cooperate to accomplish a common purpose
organism
o made up of 11 systems
o highest level of structural organization
Principal systems:
1.
integumentary
a. skin
i. waterproofs the body
ii. cushions and protects
iii. excretes salts and urea in perspiration
iv. helps to regulate body temperature
b. receptors
i. pain
ii. pressure
iii. temperature
2.
Skeletal
a. Bones, cartilage, ligaments and joints
i. Supports the body and provides a framework for skeletal
muscles to do work.
b. has a protective function
i. skull
c. hematopoiesis
i. formation of blood cells
d. storage of minerals
3.
Muscular
a. Have one function…to contract (shorten)
i. Types
1. skeletal
2. cardiac
3. smooth
4.
Nervous
a. Body’s fast acting control system
b. Cosists of:
i. Spinal cord
ii. Brain
iii. Nerves
iv. Sensory receptors
5.
Endocrine
a. Body’s slow acting control system
b. Produces chemical molecules called hormones
i. Released into blood
ii. Travel to distant organs
c. made up of:
i. pituitary gland
ii. throid gland
iii. parathyroid glands
iv. adrenal glands
v. thymus
vi. pancreas
vii. pineal
viii. ovaries (female)
ix. testes (male)
6.
Cardivascular
a. Heart and blood vessels
i. Uses blood to transport to and from tissues:
1. oxygen
2. nutrients
3. hormones
4. other substances
7.
Lymphatic
a. Complements the cardiovascular system
i. Includes
1. lymphatic vessels
2. lymph nodes
3. spleen
4. tonsils
ii. return leaked fluids to the cv system
iii. work extensively on immunity
8.
Respiratory
a. Keeps the body constantly supplied with oxygen and removed carbon
dioxide.
b. Consists of:
i. Nasal passages
ii. Pharynx
iii. Larynx
iv. Trachea
v. Bronchi
vi. Lungs
1. contain tiny air sacks
a. alveoli
b. gaseous exchange takes place here
9.
digestive
a. tube running from mouth to anus
i. include
1. oral cavity (mouth)
2. esophagus
3. stomach
4. small and large intestines
5. rectum
ii. role is to break down food and deliver products to the blood
iii. undigested food is expelled as feces
b. breakdown
i. starts in the mouth
ii. ends in the small intestine
iii. end of digestive system is for reabsorption of fluids
c. other organs
i. liver
1. produces bile to breakdown fats
ii. pancreas
1. insulin to transport sugars
10.
Urinary
a. Removes wastes from the body
i. Usually nitrogen containing products
b. AKA excretory system
c. Composed of
i. Kidneys
ii. Ureters
iii. Bladder
iv. Urethra
d. maintains body salt and water balance
e. regulates acid and base balance of blood as well
11.
Reproductive
a. Function is to produce offspring
i. Sperm are produced by the males
1. structures
a. scrotum
b. penis
c. accessory glands
d. duct system
ii. Eggs are produed by the females
1. structures
a. uterine tubes
b. uterus
c. vagina