Mastering A&P Exam 2

Which layer of the typical vessel can be regulated to constrict or dilate the lumen?

tunica media

Arteries always carry oxygenated blood away from the heart. True or false ?

False

Which of the following form successively larger vessels that carry blood toward the heart?

veins

Which of the following is true regarding veins?

Veins have valves; arteries do not.

Factors that aid venous return include all EXCEPT ________.

urinary output

An increase in blood viscosity will cause an increase in total peripheral resistance. True or False?

True

Which of the following would decrease total peripheral resistance to blood flow?

decreasing the hematocrit

Which of the following is NOT an important source of resistance to blood flow?

blood vessel diameter

What blood vessel experiences the steepest drop in blood pressure?

arterioles

The pulse pressure is ________.

systolic pressure minus diastolic pressure

**Circulatory shock**

Due to inadequate blood flow to meet tissue needs

**Vascular shock**

Normal blood volume but poor circulation due to extreme vasodilation

Cardiogenic shock

Results from heart inability to sustain adequate circulation due to myocardial damage

**Hypovolemic shock**

Due to large-scale blood loss

Select the correct statement about blood flow.

Blood flow through the entire vascular system is proportional to cardiac output

The baroreceptors in the carotid sinus and aortic arch are sensitive to which of the following?

changes in arterial pressure

Where are the sensors for the arterial baroreceptor reflex located?

carotid sinus and aortic arch

If blood pressure is increased at the arterial baroreceptors, what would happen with the activity level of the parasympathetic nervous system (PNS) and sympathetic nervous system (SNS)?

increased PNS activity and decreased SNS activity

Which of the following would cause vasodilation of arterioles?

decreased activity of the sympathetic nervous system

Stimulation of the adrenal medulla would result in which of the following?

an increase in heart rate and contractility

A decrease in blood pressure at the arterial baroreceptors would result in which of the following?

an increase in heart contractility

Which of the following is a myogenic factor that influences blood flow?

stretch of vascular smooth muscle

Which of the following organs would experience decreased blood flow during exercise?

kidneys

Blood flow to the skin ________.

increases when environmental temperature rises

Where in the body would you find low oxygen levels causing vasoconstriction and high levels causing vasodilation?

lungs

Which of the following statements describes the significance of blood pressure changes as blood reaches the capillary beds?

Blood pressure drops as it reaches the capillary beds because high pressure would rupture them.

In the capillaries, hydrostatic pressure (HP) is exerted by __________.

blood pressure

The net hydrostatic pressure (HP) is the hydrostatic pressure in the __________ minus hydrostatic pressure in the __________.

capillary; interstitial fluid

Which of the following would reflect the typical net hydrostatic pressure (HP) at the arterial end of the capillary?

34 mm Hg

The colloid osmotic pressure in the capillary is caused by __________.

proteins in the blood

Which net pressure draws fluid into the capillary?

net osmotic pressure

Reabsorption of fluid into the capillary takes place at the arterial end or venous end of the capillary?

venous

Which vessel leaves the right ventricle of the heart to take oxygen-poor, dark red blood into pulmonary circulation?

pulmonary trunk

Which vessel(s) return(s) oxygenated blood to the left atrium of the heart to complete the pulmonary circuit?

pulmonary vein

What is the main function of the lymphatic system?

The lymphatic system returns leaked fluid and plasma proteins that escape from the bloodstream to the blood.

Which of the following distinguishes lymphatic vessels from veins?

lymphatics collect larger materials

Lymph from the right leg ultimately is delivered to which duct in the thoracic region?

thoracic duct

Select the correct statement about lymph transport.

Lymph transport depends on the movement of adjacent tissues, such as skeletal muscles.

The lymphatic capillaries function to absorb the excess protein-containing interstitial fluid and return it to the bloodstream. True or false?

True

Digested fats are absorbed from the intestine by the lymph capillaries. True or false ?

True

Which lymphoid organ extracts aged and defective blood cells and platelets from the blood in addition to storing some of the breakdown products for later reuse?

The spleen harbors macrophages that ingest and recycle materials from erythrocytes that have aged or become damaged.

Which of these lymphoid organs is the thymus?

The thymus is located in the inferior neck and superior thorax profound to the superior sternum.

Which of the following would NOT be classified as a lymphoid organ?

pancreas

Which of the following is a role of lymph nodes?

They filter lymph.

Flow of lymph through a lymph node is slowed due to

fewer efferent vessels draining it compared to many afferent vessels feeding it

Functions of the spleen include all of those below EXCEPT ________.

forming crypts that trap bacteria

Which of the following lymphoid organs is NOT matched with its function?

Peyer's patches: site of B cell maturation

The thymus functions strictly in maturation of B cells. True or False?

False

The thymus is the only lymphoid organ that does NOT ________.

directly fight antigens

Which of the following provides a first line of defense against pathogens?

skin and mucous membranes

Four (or five) cardinal signs indicate inflammation. What specific sign of inflammation is the result of exudate in the tissue spaces?

edema (swelling)

Which of the following inflammatory chemicals is/are released by mast cells?

histamine

What protein can be released by infected cells to help protect cells that have not yet been infected?

interferon

How do interferons protect against viral infection in healthy cells?

Interferons encourage the production of antiviral proteins.

Which of the following phases involves white blood cells leaving capillaries?

diapedesis

Which of the following is an effect of complement activation?

opsonization

Inflammation ________.

brings more leukocytes to the site of infection

All but one of the following occurs during the inflammatory response. Select the example below that does NOT describe the process of inflammation.

Vasoconstriction prevents excessive blood loss due to injury.

Which of the following is NOT a role of activated complement?

prevention of immediate hypersensitivity reactions

Complement proteins and antibodies coat a microorganism and provide binding sites, enabling macrophages and neutrophils to phagocytize the organism. This phenomenon is termed ________.

opsonization

Soluble proteins secreted by plasma cells are called antibodies. True or False?

True

**Regulatory T cell**

Slows or stops the immune response

B cell

Forms antibody producing cells

Helper T cell

Absence results in no immune response

**Memory cell**

Enables quick and efficient response to secondary exposure to antigen

**Cytotoxic T cell**

Kills cancer cells and virus infected body cells

How does a lymphocyte exhibit immunocompetence?

by being able to recognize their one specific antigen

Which of the following is not an antigen-presenting cells (APC)?

T cell

B lymphocytes develop immunocompetence in the ________.

bone marrow

Which of the following cells engulf antigens by phagocytosis and present fragments of them on their own surfaces for recognition?

dendritic cells

The antivenom used to treat a venomous snake bite is an antibody produced in an animal such as a horse. Suppose these antibodies are injected into a patient who has been bitten by a venomous snake. How would you classify the resulting humoral immunity?

passive immunity, artificially acquired

Which of the following best illustrates artificially acquired active humoral immunity?

vaccines

What part of the antibody's structure determines its class?

constant (C) region

Which of the following occurs when antibodies block specific sites on viruses or bacterial exotoxins?

neutralization

Which mechanism(s) of antibody action result(s) in cell lysis?

complement activation

Which of the following statements regarding the primary versus the secondary immune response is true?

A primary response results when naïve lymphocytes are activated, while a secondary response is a result of activating memory cells.

Vaccines provide what type of immunity?

artificially acquired active

Which of the following are properly matched?

IgG: most abundant antibody

Plasma cells ________

have a great deal of rough endoplasmic reticulum reflecting the fact that they secrete a tremendous amount of protein (antibody)

B cells respond to the initial antigen challenge by ________.

producing progeny cells that include plasma cells and memory cells

Which of the following statements does not describe the adaptive immune response?

It occurs immediately after the body is challenged by foreign material.

Antibodies typically act extracellularly in body fluids and are therefore considered part of the humoral branch of adaptive immunity. True or False

True

What type of cell is the precursor to the helper T cell?

CD4 cell

Which of the following activate CD8 cells?

antigen fragments on class I MHC proteins

What type of T cell can directly attack and kill other cells, such as virus-infected cells?

cytotoxic T (TC) cells

T cells achieve self-tolerance in the __________.

thymus

Which of the following are NOT appropriately matched?

helper T cells: destroy infected body cells

What occurs if a naïve T cell binds to an antigen without receiving a co-stimulatory signal?

The T cell enters a state of anergy.

Which lymphocytes act as the bridge between the cellular and humoral responses?

helper T cells

An advantage to adaptive immunity is ________

its memory cells that provide quicker, larger and more efficient immune response upon second and subsequent exposure to an antigen

Which of the following is NOT a type of T cell?

antigenic

Regulatory T cells ________.

may function in preventing autoimmune reactions

T-cell activation requires ________.

antigen binding and co-stimulation

Immunocompetence ________.

is the ability of individual cells to recognize a specific antigen by binding to it

Which of the following is/are the most specific internal defense against disease?

T cells

What types of antigen do mature T cells normally not recognize?

self-antigens

Which of the following are NOT correctly matched?

immediate hypersensitivity: allergic contact dermatitis

Allergens differ from antigens because ________

allergens produce an abnormally large immune response to what is an otherwise harmless particle

Anaphylactic shock is a rare but severe allergic response that may occur if the allergen enters the blood stream. True or False?

True

In a case of immediate hypersensitivity, the immune system responds with an allergic response on the first exposure to the allergen.True or False?

False