APHY 102 Midterm Exam - Ivy Tech

What is a hormone and how does it act?

Hormones are chemical messengers that are responsible for regulation. They are secreted into body fluids, mainly blood. It has specific actions on target tissues, which are any tissue that has specific receptors for that particular hormone.

What is a paracrine gland?

a secretion that enters interstitial fluid but affects only neighboring cells

What is an autocrine gland?

A secretion that only affects the secreting cell.

What is an endocrine gland?

A gland that secretes a substance (a hormone) into the bloodstream and act on target cells

What is an exocrine gland?

A ducted gland that produces a secretion onto a body surface.

Where is the thymus located?

mediastinum; behind the sternum

Where is the pineal gland located?

center of brain

Where are the reproductive organs located?

abdomen; pelvic

Where is the pituitary gland located?

sella turcica of the sphenoid bone; base of the brain

Where are the adrenal glands located?

on top of each kidney

Where is the pancreas located?

posterior to the stomach

What are the two steroid hormones?

Sex hormones and adrenal cortex hormones; estrogen and testosterone

Describe steroid hormones

-diffuse through cell membranes into cytoplasm or nucleus

-combine with a receptor molecule binding to DNA

-promote transcription of mRNA

-mRNA enters cytoplasm directing protein synthesis

Describe non-steroid hormones.

Amines, proteins, peptides, and glycoproteins. The endocrine gland secretes nonsteroid hormones, which body fluid carries hormone to its target cell. Hormone combines with receptor site on membrane of its target cell, activating G protein. Cellular changes produce the hormone's effects.

How is the anterior pituitary gland different than the posterior pituitary gland?

The anterior pituitary becomes an endocrine gland producing and secreting hormones for the body and connects to the posterior pituitary when fully formed. Meanwhile, the posterior pituitary remains connected to the hypothalamus, functioning as a repository for hormones produced by the hypothalamus and receiving messages from it that regulate when hormones are to be released to and through the anterior pituitary

What regulates pituitary gland secretion?

Hypothalamus

Describe tropic hormones

stimulate other endocrine glands to release hormones

anterior pituitary hormones

ACTH - controls manufacture and secretion of certain hormones from the outer layer of the adrenal gland.

FSH - controls growth and development of follicles that house egg cells in ovaries and stimulate production of sperm cells in the testes.

GH - stimulates cells to enlarge and more rapidly divide

LH - promotes secretion of sex hormones and allows release of egg cells from ovaries

PRL - promotes milk production

TSH - controls secretion of certain hormones from the thyroid

posterior pituitary hormones

ADH - reduces volume of water that kidneys secrete

Oxytocin - smooth muscle contraction and allows contraction of the uterus during childbirth and may stimulate the movement of certain fluids in the male reproductive tract during sexual activity

Thyroid hormones

Calcitonin - controls blood calcium and phosphate ion concentration

Thyroxine(T4) - more prevalent in circulation

Triiodothyronine(T3) - more potent than T4

Parathyroid hormones

PTH - increases blood calcium ion concentration and decreases blood phosphate ion concentration through actions in the bones, kidneys, and intestines

adrenal medulla hormones

epinephrine and norepinephrine - increase heart rate, BP, breathing, decrease digestion

adrenal cortex hormones

Aldosterone - helps regulate concentration of sodium and potassium ions

Cortisol - affects glucose metabolism and influences proteins and fat metabolism

Pancreas hormones

Glucagon - stimulates liver to break down glycogen into glucose

Insulin - stimulates the liver to form glycogen from glucose

Somatostatin - helps regulate glucose metabolism by inhibiting secretion of glucagon and insulin

pineal gland hormone

Melatonin - made from serotonin and regulates circadian rhythms

Thymus Gland Hormones

Thymosins - affect production and differentiation of T lymphocytes

How are glucagon and insulin alike?

Both work to keep blood glucose concentration constant

How are glucagon and insulin different?

Glucagon stimulates the liver to break down glycogen into glucose and insulin promotes the formation of glycogen from glucose

How is diabetes insipitus different from diabetes mellitus?

Diabetes insipitus - a person is insatiably thirsty and has large amounts of urine output

Diabetes mellitus - two types (type 1 and type 2). Type 1 occurs when body makes no insulin. Type 2 occurs when the body reaches insulin resistance

How are pheromones different than hormones?

Pheromones are a type of hormone that are released in small quantities and play a big role in physical attraction between people.

How does aging affect the endocrine system?

As people get older, their endocrine glands decrease in size, muscular strength decreases as GH levels decrease, ADH levels increase due to slower breakdown in liver & kidneys. Calcitonin levels decrease, and insulin resistance may develop.

Describe normal blood: number of each cell type, pH.

Blood is about 8% of body weight. Adult blood volume is about 5 L.

RBC count is usually 4,600,000-6,200,000 in males, 4,200,000-5,400,000 in females.

WBC are usually 5,000-10,000 per cubic mm of blood.

Platelets are usually 130,000-360,000 per cubic mm of blood.

Normal blood pH is around 7.4.

Describe the different formed elements and their origins

RBCs originate in red bone marrow from hemocytoblasts (stem cells) which then differentiate in a process called hematopoiesis.

WBCs are called leukocytes and are split into granulocytes and agranulocytes.

Platelets are cell fragments of megakaryocytes; they lack a nucleus and are half the size of a RBC.

Compare the formed elements of the blood.

RBCs, WBCs, and platelets all act together to maintain life. RBCs transport oxygen to the body's tissues, WBCs fight infections in the body, and platelets clot wounds that occur.

What are normal levels and percentages of RBC

4,600,000-6,200,000 in males.

4,200,000-5,400,000 in females.

4,500,000-5,100,000 in children.

RBCs are 45% of the blood.

How is the shape of a red blood cell important to its function?

It allows them to squeeze through vessel walls and transport oxygen to tissues

Why might blood volume differ from one person to the next?

It might differ depending on a person's health and age, and women tend to have lower blood volume due to their menstrual cycle.

What is hematocrit?

the ratio of the volume of red blood cells to the total volume of blood

Neutrophils

Most abundant WBC; 54-62%. Phagocytic and tend to self-destruct as they destroy foreign invaders, limiting their life span to a few days.

Eosinophils

Deep red granules in acid stain, bi-lobed nucleus, 1-3% of WBC

Basophils

release histamine and heparin, <1% of WBC

Monocytes

Largest of all blood cells, kidney or oval shaped nuclei, become macrophages, 3-9% of WBC

Lymphocytes

Slightly larger than RBC, 25-33% WBC

Compare serum versus plasma

Plasma is the liquid part of blood, in which blood cells, nutrients and hormones float.

Serum is the fluid part of blood, without the clotting factors or blood cells.

Describe the steps in clot formation

Hemostasis - the stoppage of bleeding.

1. Blood vessel spasm - smooth muscle in blood vessel contracts

2. Platelet plug formation:

a. break in vessel wall

b. blood escapes through break

c. platelets adhere to each other, to end of broken vessel, and to exposed collagen

d. platelet plug helps control blood loss

3. Blood coagulation - clot forms (occurs extrinsically or intrinsically).

What happens if clots form within blood vessels?

A thrombus is made. If it breaks loose of the vessel wall and begins circulating through the body, it is then called an embolus, which can travel into tighter vessels and get trapped, causing death.

What is edema?

Abnormal accumulation of fluid in the interstitial spaces, causing swelling of the tissues

What antigens can be found on RBC?

Antigens A, B, AB, or none.

What antibodies can be found in the plasma?

Antibodies A, B, AB, or none.

Type A

Contains A antigens on cell surface and anti-B antibodies in plasma

Type B

Contains B antigens on cell surface and anti-A antibodies in plasma

Type AB

Contains both A and B antigens on cell surface and no antibodies in plasma

Type O

Contains no antigens on cell surface and has both anti-A and anti-B antibodies in plasma (universal donor)

Type A can give to

Either Type A or Type AB

Type A can receive from

Either Type A or Type O

Type B can give to

Either Type B or Type AB

Type B can receive from

Either Type B or Type O

Type AB can give to

only AB

Type AB can receive from

A, B, AB, O

Type O can give to

A, B, AB, O

Type O can receive from

only O

How does the Rh factor affect a developing fetus and its mother?

Rh positive - presence of antigen D or other Rh antigens on the RBC membranes.

Rh negative - lack of these antigens

If a mother is Rh negative and her baby is Rh positive, her antibodies form to fight Rh-positive blood cells. If a mother is Rh positive and her baby is Rh positive, her antibodies attack the baby's RBC. Complications can lead the baby to develop erythroblastosis fetalis or hemolytic disease.

What are the functions of the cardiovascular system?

Distribution of nutrients, oxygen, wastes, hormones, electorlytes, heat, immune cells, and antibodies, fluid, electrolyte, and acid- base balance

Where is the heart found?

The heart lies in the thoracic cavity. It is posterior to the sternum, medial to the lungs, anterior to the vertebral column, and lies just above the diaphragm and beneath the 2nd rib with the apex of the heart at the 5th intercostal space.

Describe the layers of the heart wall

Epicardium- outer layer; protects the heart by reducing friction. A serious membrane that consists of connective tissue covered by epithelium, and it includes capillaries and nerve fibers.

Myocardium- middle layer; thick and consists largely of the cardiac muscle tissue that pumps blood out of the heart chambers.

Endocardium- inner layer; epithelium and underlying connective tissue. Forms a protective inner lining of the chambers and valves.

Describe the pathway of blood into, through, and out of the heart

Superior/inferior venae cavae

Right atrium

Tricuspid valve

Right ventricle

Pulmonary semilunar valve

Lungs

Blood is oxygenated and returned to heart

Pulmonary veins

Left atrium

Mitral(bicuspid) valve

Left ventricle

Aortic semilunar valve

Body cells

Describe the pathway of the cardiac conduction system

SA node - AV node - Bundle of His - Left and right bundle branches - purkinje fibers

Describe an EKG

A recordable tracing of the electrical activity of the heart that the production and conduction of action potentials in the heart produces.

What is occurring within the heart during each part of the EKG?

At the P wave of the EKG, the atria are depolarizing.

At the QRS complex, the ventricles are depolarizing and the atria are repolarizing.

At the T wave, the ventricles are repolarizing and there is a brief refractory period between the T wave and the following P wave, which allows the heart a small rest.

Describe what is happening in the heart during atrial systole/ventricular diastole and atrial diastole/ventricular systole

Atrial systole/ventricular diastole - atria are contracting and ventricles are relaxed

Atrial diastole/ventricular systole - atria are relaxed and ventricles are contracting

How are the heart sounds made?

The first heart sound "lubb" occurs during ventricular systole as a result of the A-V valves closing.

The second heart sound "dupp" occurs during ventricular diastole as a result of the pulmonary and aortic semilunar valves closing.

What terms are used to describe abnormal heart rhythms?

Arrhythmia, atrial fibrillation, bradycardia, tachycardia, defibrillation, cardiac arrest, palpitations, Supraventricular tachycardia (SVT), Ventricular tachycardia, and ventricular fibrillation.

pulmonary circulation

Circulation of blood between the heart and the lungs, oxygenating blood and removing carbon dioxide

coronary circulation

circulation of blood through the coronary blood vessels to deliver oxygen and nutrients to the heart muscle tissue

systemic circulation

flow of blood from body tissue to the heart and then from the heart back to body tissues

What factors can influence heart rate and/or blood pressure?

Cardiac output, blood volume, peripheral resistance, and blood viscosity.

As blood volume, heart rate, stroke volume, blood viscosity, and peripheral resistance increase, BP increases.

How is cardiac output figured?

Stroke volume multiplied by the heart rate, expressed in bpm. (For example, if the stroke volume is 70 mL, and the heart rate is 72 bpm, the cardiac output is 5,040 mL per minute.

Where can pulse be found in the body?

The temple (temporal a.), neck (carotid a.), chin (facial a.), inner elbow (brachial a.), wrist (radial a.), groin (femoral a.), back of the knee (popliteal a.), front of the foot (dorsalis pedis a.), back of the ankle (posterior tibial a.)

At any given moment, where can blood be found in the body?

Veins

major arteries of the body

temporal, carotid, brachial, ulnar, radial, femoral, popliteal, dorsalis pedis, posterior tibial

major veins of the body

Superior and inferior vena cava, right and left external and internal jugular and subclavian v, right and left brachiocephalic v, hepatic v, splenic v, right and left common iliac v, external and internal iliac v, femoral v, great saphenous v, small saphenous v

What is arteriosclerosis?

the thickening and hardening of the walls of the arteries

How does aging affect the cardiovascular system?

Cholesterol deposition happens in the blood vessels, the heart enlarges, cardiac muscle cells die, there is an increase in fibrous connective tissue, adipose tissue and blood pressure and a decrease in resting heart rate.

What is the function of lymph?

To absorb dietary fats, deliver fats and excess fluids to the bloodstream, collect excess interstitial fluids, and deliver foreign particles to the lymph nodes.

Describe a lymphatic vessel

Fine, thin-walled, transparent valved channels distributed through most tissues. They have 3 walls: intima, media, and adventitia.

Describe the pathway of lymph

Lymphatic capillaries

Lymphatic vessels

Afferent lymphatic vessel

Lymph nodes

Efferent lymphatic vessel

Lymphatic trunk

Collecting duct

Where can lymph nodes be found in the body?

The cervical, axillary, supratrochlear, and inguinal regions and the pelvic, abdominal and thoracic cavities.

What types of cells provide our immunity?

T cells and B cells

T cell function

cell-mediated immunity; helper T cells,

B cell function

antibody production

Compare an antigen to an antibody.

antigens cause the disease and antibodies cure it.

Describe the thymus and its role in immunity

The thymus is a soft, bi-lobed gland enclosed in a connective tissue capsule. It is the place where T cells mature.

What is the function of the thymus?

T cell maturation

What is the function of bone marrow?

produces blood cells

What is the function of lymph nodes?

to trap disease-causing bacteria; filters lymph

What is the function of the spleen?

filter blood and help fight infections

What is the function of tonsils and adenoids?

activate defensive responses to inhaled and intranasal antigens

How does stress affect immunity?

With chronic stress, the immune system stays in low gear, leaving the body vulnerable to infection and disease. Basically, it suppresses it.

What is pus?

It is the accumulation of damaged tissue and dead microbes, granulocytes, and macrophages.

primary immune response

the initial immune response to an antigen, which appears after a lag of several days