Chapter 33 Study Guide

If a person's blood pressure is 120/70, the 70 refers to the pressure

during relaxation of the heart.

In mammals, blood with a low oxygen content enters the ________ of the heart.

right atrium

Which of these animals has a heart with only two chambers?

goldfish

In fishes, blood leaving the heart goes directly to the

gills

An artificial pacemaker is a device that replaces the actions of the

sinoatrial node

The left ventricle is more muscular than the right ventricle because it must push the blood

through the body's extensive system of vessels that nourish all cells.

System purpose?

The circulatory system transports oxygen, carbon dioxide, nutrients, hormones, heat, and cellular wastes throughout the body

The heart is the

pump

The blood is the

transport medium

Blood vessels are the

tubing network

What is the direction of blood flow?

Body → Right side of the heart (oxygen poor blood) - > Lungs (picks up O2, releases CO2) → Left side of heart (oxygen rich blood → Body tissue (delivers O2 and collects CO2

Arteries

Carry blood away from the heart

Capillaries

Tiny vessels where gas and material exchnage occurs with tissues

Veins

carry blood back toward the heart

Plasma

Liquid carrying dissolved substances

Red blood cells

carry most oxygen, using hemoglobin

White blood cells

Help defend against infection

Platelets

Help form clots

• Blood pressure is generally _____ in arteries and ___ as blood moves through the vessels.

highest ; falls

In the lungs blood releases?

Carbon dioxide

In the lungs blood picks up ?

oxygen

In body tissue blood does what?

Delivers oxygen and collects carbon dioxide

What is blood pressure?

The force blood exerts on vessel walls

Why do veins contain one-way valves?

To prevent blood from flowing backward as it returns to the heart

If a person's blood pressure is 120/70, the 70 refers to the pressure

during relaxation of the heart.

In mammals, blood with a low oxygen content enters the ________ of the heart.

right atrium

Which of these animals has a heart with only two chambers?

goldfish

In fishes, blood leaving the heart goes directly to the

gills

An artificial pacemaker is a device that replaces the actions of the

sinoatrial node.

The left ventricle is more muscular than the right ventricle because it must push the blood

through the body's extensive system of vessels that nourish all cells.

Which set of chambers supplies blood to the pulmonary circulation?

Right atrium and right ventricle

Which of the following have four-chambered hearts?

birds

In which vertebrate group are there two atria but only a single ventricle?

some reptiles

In vertebrates, which heart chamber supplies oxygenated blood to the body cells?

Left ventricle

Ventricles force blood directly into the

arteries

The human heart contains cells that do all of the following EXCEPT:

create new red blood cells.

What is the cardiac cycle?

The alternating relaxation and contraction of the heart chambers

When your blood pressure is measured from an artery in your arm, it is a measurement of the pressure produced by your

left ventricle

Thrombin catalyzes the conversion of the plasma protein fibrinogen into fibrin. True or False?

true

The most abundant cell type in blood is the

erythrocyte

Plasma contains all of the following components EXCEPT

lymph

The average red blood cell lives for about ________ days.

120

Which of the following does NOT play a role in blood clotting?

albumin

Which of these blood cells have no nucleus in mammals?

red blood cells

Erythropoietin stimulates the manufacture of

red blood cells

Which of the following is a leukocyte that engulfs and destroys bacteria?

neutrophil

Why do red blood cells contain hemoglobin?

Hemoglobin can bind and carry four molecules of oxygen simultaneously.

What drives the return of blood to the heart in the systemic veins?

Muscles squeezing blood through the veins

Imagine that you are about to give blood for the first time. While watching other donors around you, you become pale and have to sit down before you faint. Which vessels constricted to produce this nervous side effect?

Arterioles

Which of the following types of blood vessels are directly involved in the exchange of materials between blood and tissues?

Capillaries

What happens to the speed of blood as it passes through the capillaries?

It decreases greatly.

The accumulation of carbon dioxide, lactic acid, or other cellular waste causes nearby precapillary sphincters to

relax

Hypertension may lead to

low blood pressure

Suggest a way that interstitial fluid (water) can be drawn back into the blood vessels.

The high osmotic pressure of the blood inside the capillaries caused by albumin draws fluid back into the vessels by osmosis.

Bone marrow is part of the lymphatic system. True or False?

true

Lymph nodes aid in the destruction of bacteria and viruses. True or False?

true

How do lymphatic capillaries differ from blood capillaries?

they have “dead ends”

What two organs are considered to be part of the lymphatic system?

spleen and thymus

How is lymph moved along the lymphatic vessels?

Lymph moves by contractions of smooth muscles in the lymphatic vessels and contraction of nearby skeletal muscles during exercise.

All organisms that generate energy (ATP) aerobically need to take in oxygen and remove carbon dioxide from their bodies. This process is known as

respiration

The carbon dioxide that is exhaled when you breathe is produced during

cellular respiration

Why are respiratory surfaces, such as living cell membranes, moist?

Gases must dissolve in water to cross cell membranes.

Respiration provides the body with oxygen and also eliminates __________, one of the waste products of cellular respiration.

carbon dioxide

Aquatic animals that lack a circulatory system for transporting gases __________.

often have flattened bodies

What happens during countercurrent exchange in fishes?

Gas exchange occurs as blood and water move in opposite directions across a respiratory surface.

All flatworms use their skin as a respiratory organ.

true

If a respiratory surface dries out, gas exchange will

not occur

What is gas exchange?

amphibians breathing through their skin

You are a veterinarian working for the San Diego Zoo. Today, you are performing an autopsy on a 22.7-gram frog and a 21.2-gram lizard, both of which appear to have died of a respiratory infection. Why are you not surprised to find that the lungs of the lizard have a larger internal surface area than those of the frog?

Lizards have dry, scaly skin, whereas frogs have thin, moist skin.

In the lungs, oxygen moves from air into blood by

diffusion

Which of the following statements about gas exchange in animals with interacting circulatory and respiratory systems is FALSE?

Oxygen is actively transported into the circulatory system.

What are spiracles?

Openings into the tracheae of insects

Which of the following passageways delivers air directly into each lung?

bronchus

What structure prevents food from entering the larynx?

epiglottis

The vocal cords are located in the

larynx

What happens during inhalation?

The diaphragm contracts.

Which of the following is NOT part of the conducting portion of the human respiratory system?

Alveoli

Which of the following events initiates the process of exhalation?

Relaxation of the diaphragm

Which of the following structures serves as a passageway for both air and food?

Pharynx

Where does gas exchange occur in the mammalian lung?

Alveoli

Which of the following represents the correct path of air during the process of inhalation?

pharynx, larynx, trachea, bronchi, bronchioles, alveoli

Carbon dioxide can be transported in the blood by all of the following methods, EXCEPT

as CO within red blood cells.

Most of the carbon dioxide released from cells is transported in the blood as

bicarbonate ions in the plasma.

Which of the following occurs in the lungs?

Some of the oxygen in the air moves into the blood, and some of the carbon dioxide in the blood moves into the air.

In the tissues, carbon dioxide enters red blood cells and combines with water to form hydrogen ions and bicarbonate ions. How is the blood prevented from becoming too acidic as a result of bicarbonate formation?

The hydrogen ions are bound to hemoglobin.

How is a gradient maintained so that carbon dioxide will diffuse from body cells into the plasma?

Most carbon dioxide enters red blood cells where it immediately combines with water to produce bicarbonate ions and hydrogen ions.

Cells lining the alveoli are coated with a thin layer of fluid called "surfactant." What is the function of this fluid?

to prevent the alveoli from collapsing when air is exhaled