Campbell Biology Chapter 42

Small molecules can move between cells and their surroundings by

diffusion

Some animals lack a _______

circulatory system

A gastrovascular cavity

functions in both digestion and distribution of substances throughout the body

A circulatory system has

a circulatory fluid, a set of interconnecting vessels, and a muscular pump called the heart

function of the circulatory system

connects the fluid that surrounds cells with the different organs of the body

Circulatory systems can be ___ or _____ and vary in the number of ____ in the body

open, closed, and circuits

In insect, arthropods, and some molluscs, circulatry fluid called ______ bathes the organs in an _______

hemolymph, open circulatory system

In a _______ circulatory system ____ is confined to vessels and is distinct from the interstitial fluid

closed, blood

Humans and other vertebrates have a closed circulatory system called the

cardiovascular system

Three main types of bloods vessels

arteries, veins, and capillaries

Arteries branch into _____ and carry blood away from the heart to _______

aterioles capillaries

Networks of capillaries called ______ are the sites of chemical exchange between the blood and interstitial fluid

capillary beds

Venules converge into _____ and return blood from the capillaries to the heart

veins

Arteries and veins are distinguished by the direction of blood flow

arteries carry blood away from heart; veins to heart

blood enters through an _____ and is pumped out through a _____

atrium and ventricle

Bony fishes, rays, and sharks have a _____ circulation with a _____ chambered heart

single, two

Single circulation

blood leaving the heart passes through two capillary beds before returning

Amphibians, reptiles, and mammals have _______

double circulation

Oxygen poor and oxygen rich blood are pumped separately from the

right and left sides of the heart

Oxygen rich blood delivers oxygen through the

systemic circuit

frogs and other amphibians have a three chambered heart

two atria and one ventricle

Turtles snakes and lizards have a three chambered heart

two atria and one ventricle, partially divided by an incomplete septum

mammals and birds have a four chambered heart

two atria and two ventricles

the left side of the heart pumps and receives

oxygen rich blood

the right side receives and pumps

oxygen poor blood

Cardiovascular system

Mammalian heart

The heart contracts and relaxes in a rhythmic cycle called the

cardiac cycle

the contraction or pumping phase is called

systole

the relaxation or filling phase is called

diastole

The number of beats per minute is called the

heart rate

the amount of blood pumped in a single contraction is called the

stroke volume

The volume of blood pumped into the systemic circulation, it depends on both the heart rate and stroke volume

cardiac output

atrioventricular valves

separate each atrium and ventricleg

semilunar valves

control blood flow to the aorta and pulmonary artery

"lub dup" sound of a heart beat is caused by the recoil of blood against the ____ valves then against the _____ valves

AV, semilunar

Backflow of blood through a defective valve causes a

heart murmur

Autorhythmic

contraction without signal from the nervous system

sinoatrial (SA) node or pacemaker sets

the rate and timing at which cardiac muscle cells contract

impulses that travel during the cardiac cycle can be recorded as an

electrocardiogram (ECG or EKG)

Impulses from the SA node travel to the

atrioventricular (AV) node

at the av node the impulses are delayed and then travel to the

purkinje fibers that make the ventricles contract

the pacemaker is regulated by two portions of the nervous system

the sympathetic and parasympathetic divisions

the sympathetic division speeds up the

pacemaker

the parasympathetic division slows down

the pacemaker

the pacemaker is also regulated by

hormones and temperature

A blood vessels cavity is called the

central lumen

the epithelial layer that lines blood vessels is called the

endothelium

the endothelium is

smooth and minimizes resistance

Which has thicker walls, arteries or veins

Arteries, to accommodate the high pressure of blood pumped from the heart

Velocity of blood flow is slowest where

the capillary beds, as a result of the high resistance and large total cross sectional area

Blood flow in capillaries is necessarily ____ for exchange materials

slow

T or F Blood flows from areas of lower pressure to higher pressure

FALSE, blood flows from high to low

Systolic pressure

the pressure in the arteries during ventricular systole; it is the highest pressure in the arteries

diastolic pressure

the pressure in the arteries during diastole; it is lower than systolic pressure

Pulse

the rhythmic bulging of artery walls with each heartbeat

Vasoconstriction

the contraction of smooth muscle in arteriole walls; it increases blood pressure

Vasodilation

the relaxation of smooth muscles in the arterioles; it causes blood pressure to fall

_____ is a major inducer of vasodilation

Nitric oxide

The peptide _____ is a strong inducer of vasoconstriction

endothelin

The system that returns fluid that leaks out from the capillary beds

lymphatic

fluid lost by capillaries is called

lymph

Edema

swelling caused by disruptions in the flow of lymph

Lymph nodes are

organs that filter lymph and play an important role in the body's defense

Blood in vertebrates is a connective tissue consisting of several kinds of cells suspended in a liquid matrix called

plasma

The composition of mammalian blood

Platelets

fragments of cells that are involved in clotting

Erythrocytes

the most numerous blood cells

hemoglobin

iron containing protein that transports O2

Sickle cell disease is caused by

abnormal hemoglobin proteins that form aggregates

5 major types of white blood cells or leukocytes

monocytes, neutrophils, basophils, eosinophils, and lymphocytes

They function in defense either by _______ bacteria or mounting immune responses

phagocytizing

Platelets are fragments of cells and function in

blood clotting

Erythrocytes, leukocytes, and platelets all develop from a common source of

stem cells in the red marrow of bones

The hormone erythropoietin

stimulates erythrocyte production when O2 delivery is low

Coagulation

the formation of a solid clot from liquid blood

A blood clot formed within a blood vessel is called a ____ and can block blood flow

thrombus

Atherosclerosis

caused by the buildup of fatty deposits (plaque) within arteries

Low-density lipoprotein (LDL)

delivers cholesterol to cells for membrane production

High density lipoprotein (HDL)

scavenges excess cholesterol for return to the liver

Heart attack or myocardial infarction

the damage or death of cardiac muscle tissue resulting from blockage of one or more coronary arteries

stroke

nervous tissue in the brain usually resulting from rupture or blockage of arteries in the head

Angina pectoris

chest pain caused by partial blockage of the coronary arteries

Gas exchange supplies O2 for ________ and disposes of CO2

cellular respiration

Partial pressure is the pressure exerted by a _____ in a mixture of gases

particular gas

Ventilation moves the respiratory medium over the

respiratory surface

Lungs

an infolding of the body surface

Swallowing moves the ____ upward and tips the epiglottis over the glottis in the pharynx to prevent food from entering the ______

larynx and trachea

Air passes through the

pharynx, larynx, trachea, bronchi, and bronchioles to the alveoli, where gas exchange occurs

Cilia and mucus line the epithelium of the air ducts to

move particles up to the pharynx

Gas exchange takes place in

alveoli, air sacs at the tips of bronchioles

surfactants

secretions that coat the surface of the alveoli

Breathing

the process that vetilates the lungs, the alternate inhalation and exhalation of air

Positive pressure breathing

ventilation by forcing air down the trachea

Negative Pressure breathing

pulls air into the lungs

Lung volume increases as the rib muscles and ______ contract

diaphragm

Tidal volume

is the volume air inhaled with each breath

vital capacity

maximum tidal volume

after exhalation a _______ of air remains in the lungs

residual volume

respiratory pigments

proteins that transport oxygen, greatly increase the amount of oxygen that blood can carry