Anatomy and Physiology II Midterm

Paracrine secretion

Paracrine secretion

affect neighbouring cells

Local hormone

hormones that act locally without first entering the blood stream

Autocrine secretions

affect only the secreting cell itself

Exocrine gland

A gland (as a sweat gland, a salivary gland, or a kidney) that releases a secretion external to or at the surface of an organ by means of a canal or duct.

Endocrine gland

a ductless gland that secretes hormones directly into the bloodstream

Primary gland

hormone secretion

Secondary gland

produce hormones as well as other substances

How do steroid hormones travel?

through blood on protein carriers

Where are steroid hormone receptors located?

inside the cell

How do non-steroid hormones travel?

travel dissolved in blood- may need a carrier protein for protection from enzymes
water soluble

Where are non-steroid hormone receptors?

cell membrane

First messenger

A water soluble hormone that binds to its receptor at the outer surface of the plasma membrane and initiates intracellular activity

Second messenger

A small, nonprotein, water-soluble molecule or ion that relays a signal to a cell's interior in response to a signal received by a signal receptor protein.

Signal transduction

A series of molecular changes that converts a signal on a target cell's surface to a specific response inside the cell (cell communication)

What do prostaglandins do?

communicate with cells to signal healing measures

Where is the pituitary gland located?

base of the brain

What controls the pituitary gland?

hypothalamus

What is growth hormone (GH) responsible for? What is it controlled by?

GH is responsible for body growth and blood glucose levels (glycolysis, gluconeogenesis)
GH is controlled by the hypothalamus

What is prolactin (PRL) responsible for? What is it controlled by?

PRL is responsible for lactation, menstruation, and fertility
PRL is controlled by the hypothalamus

What is thyroid-stimulating hormone (TSH) responsible for? What is it controlled by?

TSH regulates thyroid hormones
TSH is controlled by the hypothalamus

What is adrenocorticotropic hormone (ACTH) responsible for? What is it stimulated by?

ACTH stimulates adrenal glands to release cortisol and androgens
ACTH is stimulated by the hypothalamus

What is follicle-stimulating hormone (FSH) responsible for? What is it stimulated by?

FSH regulates menstruation and egg production
FSH is stimulated by the hypothalamus

What is luteinizing hormone (LH) responsible for? What is it stimulated by?

LH is responsible for maturation of germ cells, causes Leydig cells to produce testosterone, and for creation of steroid hormones from ovaries
LH is stimulated by the hypothalamus

What are the two posterior pituitary hormones?

Antidiuretic hormone (ADH) and oxytocin (OT)

What is the function of antidiuretic hormone (ADH)? What is it controlled by?

tells kidneys to conserve water and may cause blood vessels to constrict
ADH is controlled by the hypothalamus

What is the function of oxytocin (OT)? What is it controlled by?

has roles in childbirth, putting milk in milk ducts, bonding, and male sexual response
OT is controlled by the hypothalamus

Where is the thyroid gland located?

anterior neck

What are the thyroid hormones?

thyroxine (T4), triiodothyronine (T3), and calcitonin

What are the functions of T3 and T4? What are they controlled by?

T3 and T4 are responsible for energy metabolism regulation
They are controlled by the hypothalamus and pituitary gland

What is the function of calcitonin? What is it controlled by?

Calcitonin lowers blood levels of calcium when too high and increases calcium storage rate in bones and urine
It is controlled by calcium blood concentration

Where is the parathyroid gland located?

posterior of thyroid

What is the function of parathyroid hormone (PTH)?

increases calcium blood concentration

What are the two parts of the adrenal glands?

adrenal medulla (inner) and adrenal cortex (outer)

What is the function of epinephrine and norepinephrine? What are they regulated by?

they resemble affects of SNS neurotransmitters
They are regulated through the sympathetic division of the adrenal medulla

What is the function of aldosterone? What is it stimulated by?

plays a role in electrolyte concentration and blood volume/BP regulation
It is stimulated by potassium ions in the blood and comes from the adrenal cortex

What is the function of cortisol? What triggers its release?

influences glucose, protein, and fat metabolism in response to stress
stress, injury, or disease trigger release from the adrenal cortex

Which part of the adrenal gland produces adrenal sex hormones?

inner zone of adrenal cortex

Where is the pineal gland located? What does it secrete?

near the upper portion of the thalamus
it secretes melatonin

Where is the thyroid gland located? What does it secrete?

lies between the lungs, behind sternum
secretes thymosins and has a role in immunity

Hematopoiesis

blood cell production

Reticulocyte

immature RBC without a nucleus

Erythropoiesis

production of RBCs

Erythropoietin (EPO) function

stimulates RBC production when low O2 levels are detected

Where is EPO secreted from?

kidneys and liver

Polycythemia

slow moving blood, O2 deficiency

Hemorrhagic anemia

RBCs destroyed faster than they're being made

Hemolytic anemia

over-destruction of RBCs, fewer RBCs than normal

Pernicious anemia

diminished ability to absorb vitamin B12

Megaloblastic anemia

RBCs are too big (underdeveloped) and can't travel

Aplastic anemia

destruction of red bone marrow

Iron-deficiency anemia

caused by inadequate iron intake

Sickle-cell anemia

RBCs are C (sickle) shaped and can't travel
- causes decreased O2 transport
- RBCS are fragile

Thalassemias

not enough hemoglobin made
- decreased O2 levels

What is the life cycle of an RBC?

1. begins in the small intestine and absorbs nutrients
2. RBCs are produced in red bone marrow, then they travel through the body for 120 days
3. Old RBCs go to the liver to be broken down
4. Hemoglobin is turned to globin and heme
5. Heme is turned to iron (recycled) and biliverdin
6. Biliverdin is turned to bilirubin and either goes to the kidney for excretion, or it is sent to the small intestine
7. nutrients are recycled and cycle repeats

What are the 2 categories of WBCs?

granulocytes and agranulocytes

Neutrophils

a type of granulocyte that engulfs invaders

Eosinophils

a type of granulocyte with roles in parasitic infections and allergic reactions

Basophils

a type of granulocyte with roles in allergic reactions and inflammation

Monocyte

a type of agranulocyte which engulfs invaders

Lymphocytes

a type of agranulocyte which is long-lived and includes T lymphocytes, B lymphocytes, and NK cells

Thrombocytosis

an abnormal increase in the number of platelets in the circulating blood
- caused by infection or genetic defect

What are the three types of plasma proteins?

albumins, globulins, fibrinogen

What is albumin responsible for? What is it synthesized by?

responsible for osmotic pressure and synthesized by the liver

What is the function of globulins?

to transport substances such as antibodies

What is the function of fibrinogen?

blood clotting

Hemostasis

stoppage of bleeding

What are the 3 steps of hemostasis?

1. blood vessel spasm
2. platelet plug formation
3. blood coagulation

Fibrinolysis

Breakdown and removal of a clot

Embolus

moving blood clot

Coronary thrombosis

obstruction of a coronary artery by a clot

Cerebral thrombosis

presence of a stationary clot in a blood vessel of the brain

Type A blood

A antigens and anti-B antibodies

Type B blood

B antigens and anti-A antibodies

Type AB blood

A and B antigens, no antibodies

Type O blood

no antigens, A and B antibodies

Rh positive

having Rh factor on surface of blood cells

Rh negative

lacking Rh factor on surface of blood cells

Erythroblastosis fetalis

a disorder that results from the incompatibility of a fetus with Rh-positive blood and a mother with Rh-negative blood, causing red blood cell destruction in the fetus; a blood transfusion is necessary to save the fetus

Pulmonary circuit

carries blood to the lungs for gas exchange and returns it to the heart

Systemic circuit

transports blood to and from the rest of the body

Pericardium

membranous sac enclosing the heart

Fibrous pericardium

outer layer is a tough, connective tissue

Serous pericardium

inner layer is thinner, more delicate membrane

Serous fluid

watery fluid surrounding heart to reduce friction against pericardium

What are the 3 layers of the wall of the heart?

epicardium, myocardium, endocardium

Epicardium

outermost layer of heart wall, same as visceral pericardium

Myocardium

thick middle layer of heart wall, consists of cardiac muscle

Endocardium

innermost layer of the heart, contains Purkinje fibers

Purkinje fibers

specialized conductive fibers located within the walls of the ventricles

Atria

upper chambers of the heart, thin walls

Auricles

"flaps" on the atria to increase the volume of the chamber

Ventricles

thick lower chambers of the heart, pump blood out to the lungs and body

Septum

Divides the right and left chambers of the heart

What is the right AV valve also called?

tricuspid valve

Tricuspid valve

valve between the right atrium and the right ventricle

What is the left AV valve also called?

bicuspid or mitral valve

Bicuspid valve

valve between the left atrium and the left ventricle.

Chordae tendineae

thin bands of fibrous tissue that attach to the valves in the heart and prevent them from inverting

Where do chordae tendineae originate from?

papillary muscles

Pulmonary valve

valve positioned between the right ventricle and the pulmonary artery