Exam 1 Ap 2

hypothalamus

links nervous & endocrine systems

Pituitary gland

“master gland,” controls other gland

Pineal Gland

melatonin, sleep cycle

Thyroid

metabolism, growth

Parathyroid glands

calcium balance

adrenal gland

stress response

pancreas

blood glucose regulation

gonads (ovaries/ testes)

sex hormones, reproduction

Major classes of hormones

peptide hormones, steroid hormones, amine hormones

Peptide hormones

water soluble, bind to cell surface receptors, fast acting

steroid hormones

lipid soluble, enter the cell and affect gene transcription, slower but longer lasting

Amine hormones

derived from amino acids, can act like peptide or steroid hormones,

Hypothalamus

controls the pituitary

Pituitary

releases hormones that control other endocrine glands

Insulin

lowers blood glucose

glucagon

raises blood glucose levels

Thyroxine (T4)

increase metabloism

Aldosterone

sodium and water retention

ADH

water reabsorption by kidneys, controls water balance

Cortisol

stress response and increases glucose

Epinephrine

increase heart rate and energy availabilty

aldosterone

regulates sodium and potassium

insulin and glucagon

regulate blood glucose

thyroid hormones

regulate metabolic rate

SA node

Serves as the heart's natural pacemaker, controlling heart rate and rhythm.

AV node

delays impulse

AV bundle

conducts signals

Cardias Conduction system

SA node, AV node, AV bundle, and Purkinje fibers work together to transmit electrical impulses throughout the heart.

Purkinje fibers

stimulate ventricular contraction

cardiac Cycle

the series of events that occur during one heartbeat, including contraction and relaxation phases of the heart.

Diastole

heart relaxes, chamber fills

Systole

heart contracts, blood is pumped

Artieries

carry blood away from the heart, thick elastic walls, high pressure, no valves

veins

carry blood to the heart, thinner walls, lower pressure, contain valves

factors inlfuenecing blood flow

blood pressure, vessel diameter, blood viscosity, peripheral resistance, cardiac output

arteries

this is where there is the highest pressure in circuits

veins

this is where there is the lowest pressure in circuits

Transport of oxygen

mostly bound to hemoglobin, small amount dissolved in plasma

transport of carbon dioxide

mostly as bicarbonate ions, some bond to hemoglobin, some dissolved in plasma

Lymphatic system functions

returns excess fluid to bloodstream, absorbs dietary fats, immune defense

lymphatic system structures

lymphatic vessels, lymph nodes, spleen, thymus, tonsils