LIFE 1409 Exam #1

Endocrine glands ________.

secrete chemical messengers that travel in the bloodstream

Chemical signaling that affects neighboring cells is called ________.

paracrine

A newly developed pesticide has been observed to bind to an intracellular hormone receptor. If ingested, residue from this pesticide could disrupt levels of ________.

thyroid hormone

A small molecule binds to a G protein, preventing its activation. What direct effect will this have on signaling that involves cAMP?

Adenylyl cyclase will not be activated

A student is in a car accident, and although not hurt, immediately experiences pupil dilation, increased heart rate, and rapid breathing. What type of endocrine system stimulus did the student receive?

neural

The hypothalamus is functionally and anatomically connected to the posterior pituitary lobe by a bridge of ________.

nerve axons

Which of the following is an anterior pituitary hormone?

TSH

How many hormones are produced by the posterior pituitary?

0

Which of the following hormones contributes to the regulation of the body’s fluid and electrolyte balance?

antidiuretic hormone

Which of the following statements about the thyroid gland is true?

1) It is located anterior to the trachea and inferior to the larynx

2) The parathyroid glands are embedded within it

3) It manufactures three hormones

The secretion of thyroid hormones is controlled by ________.

TSH from the anterior pituitary

The development of a goiter indicates that ________.

there is an excessive accumulation of colloid in the thyroid follicles

Iodide ions cross from the bloodstream into follicle cells via ________.

active transport

When blood calcium levels are low, PTH stimulates ________.

the activity of osteoclasts

Which of the following can result from hyperparathyroidism?

fractures

The adrenal glands are attached superiorly to which organ?

kidneys

What secretory cell type is found in the adrenal medulla?

chromaffin cells

Cushing’s disease is a disorder caused by ________.

abnormally high levels of cortisol

Which of the following responses is not part of the fight-or-flight response?

reduced mental activity

What cells secrete melatonin?

pinealocytes

The production of melatonin is inhibited by ________.

exposure to bright light

The gonads produce what class of hormones?

steroid hormones

The production of FSH by the anterior pituitary is reduced by which hormone?

inhibin

The function of the placental hormone human placental lactogen (hPL) is to ________.

prepare the breasts for lactation

If an autoimmune disorder targets the alpha cells, production of which hormone would be directly affected?

glucagon

Which of the following statements about insulin is true?

Insulin facilitates the movement of intracellular glucose transporters to the cell membrane

The walls of the atria produce which hormone?

atrial natriuretic peptide

The end result of the RAAS is to ________.

increase blood pressure

Athletes may take synthetic EPO to boost their ________.

blood oxygen levels

Hormones produced by the thymus play a role in the ________.

development of T cells

The anterior pituitary gland develops from which embryonic germ layer?

oral ectoderm

In the elderly, decreased thyroid function causes ________.

decreased basal metabolic rate

Which of the following statements about blood is true?

blood is slightly more viscous than water

Which of the following statements about albumin is true?

it is the most abundant plasma protein

Which of the following plasma proteins is not produced by the liver?

immunoglobulin

Which of the formed elements arise from myeloid stem cells?

platelets

Which of the following statements about erythropoietin is true?

it facilitates the proliferation and differentiation of the erythrocyte lineage

Interleukins are associated primarily with which of the following?

1. production of various lymphocytes

2. immune responses

3. inflammation

Which of the following statements about mature, circulating erythrocytes is true?

they have no nucleus

A molecule of hemoglobin ________.

consists of four globin proteins, each bound to a molecule of heme

The production of healthy erythrocytes depends upon the availability of ________.

copper, zinc, and vitamin B₁₂

Aging and damaged erythrocytes are removed from the circulation by ________.

macrophages

A patient has been suffering for 2 months with a chronic, watery diarrhea. A blood test is likely to reveal ________.

polycythemia

The process by which leukocytes squeeze through adjacent cells in a blood vessel wall is called ________.

emigration

Which of the following describes a neutrophil?

abundant, granular, especially effective against bacteria

T and B lymphocytes ________.

are involved with specific immune function

A patient has been experiencing severe, persistent allergy symptoms that are reduced when she takes an antihistamine. Before the treatment, this patient was likely to have had increased activity of which leukocyte?

basophils

Thrombocytes are more accurately called ________.

platelets

The first step in hemostasis is ________.

vascular spasm

Prothrombin is converted to thrombin during the ________.

common pathway

Hemophilia is characterized by ________.

inadequate production of clotting factors

The process in which antibodies attach to antigens, causing the formation of masses of linked cells, is called ________.

agglutination

People with ABO blood type O ________.

lack both antigens A and B on their erythrocytes

Hemolytic disease of the newborn is a risk during a subsequent pregnancy in which ________.

an Rh⁻ person is carrying a second Rh⁺ fetus

Which of the following is not important in preventing backflow of blood?

endocardium

Which valve separates the left atrium from the left ventricle?

mitral

Which of the following lists the valves in the order through which the blood flows from the vena cava through the heart?

tricuspid, pulmonary semilunar, bicuspid, aortic semilunar

Which chamber initially receives blood from the systemic circuit?

right atrium

The ________ layer secretes chemicals that help to regulate ionic environments and strength of contraction and serve as powerful vasoconstrictors.

endocardium

The myocardium would be the thickest in the ________.

left ventricle

In which septum is it normal to find openings in the adult?

atrioventricular septum

Which of the following is unique to cardiac muscle cells?

Only cardiac muscle is capable of autorhythmicity

The influx of which ion accounts for the plateau phase?

calcium

Which portion of the ECG corresponds to repolarization of the atria?

none of the above: atrial repolarization is masked by ventricular depolarization

Which component of the heart conduction system would have the slowest rate of firing?

Purkinje fibers

The cardiac cycle consists of a distinct relaxation and contraction phase. Which term is typically used to refer ventricular contraction while no blood is being ejected?

isovolumic contraction

Most blood enters the ventricle during ________.

atrial diastole

The first heart sound represents which portion of the cardiac cycle?

closing of the atrioventricular valves

Ventricular relaxation immediately follows ________.

ventricular repolarization

The force the heart must overcome to pump blood is known as ________.

afterload

The cardiovascular centers are located in which area of the brain?

medulla oblongata

In a healthy young adult, what happens to cardiac output when heart rate increases above 160 bpm?

It decreases

What happens to preload when there is venous constriction in the veins?

it increases

Which of the following is a positive inotrope?

Ca²⁺

The earliest organ to form and begin function within the developing human is the ________.

heart

Of the three germ layers that give rise to all adult tissues and organs, which gives rise to the heart?

mesoderm

The two tubes that eventually fuse to form the heart are referred to as the ________.

cardiogenic tubes

Which primitive area of the heart will give rise to the right ventricle?

bulbus cordis

The pulmonary trunk and aorta are derived from which primitive heart structure?

truncus arteriosus

The endothelium is found in the ________.

tunica intima

Nervi vasorum control ________.

both vasoconstriction and vasodilation

Closer to the heart, arteries would be expected to have a higher percentage of ________.

elastic fibers

Which of the following best describes veins?

thin walled, large lumens, low pressure, have valves

An especially leaky type of capillary found in the liver and certain other tissues is called a ________.

sinusoid capillary

In a blood pressure measurement of 110/70, the number 70 is the ________.

diastolic pressure

A healthy elastic artery ________.

is compliant

Which of the following statements is true?

As blood volume decreases, blood pressure and blood flow also decrease

Slight vasodilation in an arteriole prompts a ________.

huge decrease in resistance

Venoconstriction increases which of the following?

1. blood pressure within the vein

2. blood flow within the vein

3. return of blood to the heart

Hydrostatic pressure is ________.

the pressure exerted by fluid in an enclosed space

Net filtration pressure is calculated by ________.

subtracting the blood colloid osmotic pressure from the capillary hydrostatic pressure

Which of the following statements is true?

In one day, more fluid exits the capillary through filtration than enters through reabsorption

Clusters of neurons in the medulla oblongata that regulate blood pressure are known collectively as ________.

the cardiovascular center

In the renin-angiotensin-aldosterone mechanism, ________.

aldosterone prompts the kidneys to reabsorb sodium

In the myogenic response, ________.

vascular smooth muscle responds to stretch

A form of circulatory shock common in young children with severe diarrhea or vomiting is ________.

hypovolemic shock

The coronary arteries branch off of the ________.

ascending aorta

Which of the following statements is true?

the radial and ulnar arteries join to form the palmar arch

Arteries serving the stomach, pancreas, and liver all branch from the ________.

celiac trunk

The right and left brachiocephalic veins ________.

1. drain blood from the right and left internal jugular veins

2. drain blood from the right and left subclavian veins

3. drain into the superior vena cava