Unit 9-cardiovascular system- animal biology

How many types of blood vessels are in the cardiovascular system?

three types of blood vessels

What are the three main types of blood vessels in the cardiovascular system

Arteries, veins, and capillaries.

what do arteries do

carry blood away from the heart

what do capillaries do

permit exchange of materials with tissues

what do veins do

carry blood back to the heart

what is the inner layer of a blood vessel

endothelium

what is the middle layer of a blood vessel

smooth muscle and elastic tissue

what is the outer layer of the blood vessels

fibrous connective tissue

what is the largest artery in the human/ most mammalian bodies

the aorta

what does the aorta do

carries oxygen rich blood from the heart to other parts of the body

arteries eventually branch off into smaller what

arterioles

arterioles

can be dilated/constricted which helps blood pressure

what are capillaries

tiny vessels, single cell thick, feed all of the tissues in the body

what do capillaries do

play an important role in homeostasis

exchange of substances across thin walls

what are the exchange in substances in capillaries

Oxygen and nutrients diffuse out.

Wastes and carbon dioxide diffuse in.

Water may also leave capillaries.

Can all of the capillary beds be open at the same time

no, blood flow varies so that only some are completely open at any given time

what controls the blood flow of a capillary bed

precapillary sphincters

what 2 things take blood from capillary beds to the heart

veins and venules

what are venules

small blood vessels/veins that drain blood from capillaries and join to form a vein

what do veins have that prevent backflow of blood and direct blood toward the heart

valves

what is blood flow in veins primarily dependent on

skeletal muscle contractions

what could damage to valves from aging or disease lead to

may lead to blood pooling in the veins

what are varicose veins and hemorrhoids

caused by veins enlarging as blood pools and becomes visible at skin surface

why do veins have a greater capacity to expand

due to thinner walls

what are the largest veins

the venae cavae: includes the superior vena cava and the inferior vena cava

blood is a connective tissue that contains what

cells within a fluid matrix

what are the functions of blood

-transporting gasses nutrients, wastes, and hormones

-regulates body temperature, blood and osmotic pressures, water balance, and pH

-protects combating pathogenic microorganisms, excess loss of blood by clotting mechanisms

what are the two main portions of blood

plasma and formed elements which consist of cells and platelets

what are the functions of plasma protein

-transport: albumin transports bilirubin, lipoproteins transport cholesterol

-blood clotting: fibrinogen

-fight disease: immunoglobins

-help maintain blood volume due to large size

what is another name for red blood cells

Erythrocytes

where are red blood cells created

in red bone marrow of certain bones

what do red blood cells contain

hemoglobin

what is hemoglobin

a respiratory pigment

what is the life span of red blood cells in humans and dogs

120 days

what is the life span of red blood cells in cats

80 days

what is anemia

too few red blood cells or not enough hemoglobin

what are the three causes of anemia

-decreased production of red blood cells (iron-deficiency)

-loss of red blood cells

-destruction of red blood cells

when arterial blood carries a reduced amount of oxygen (because of anemia or high-altitude location), kidneys increase the production of what hormone

erythropoietin (EPO)

what does erythropoietin do

speeds up maturation of red blood cells in bone marrow

what is another name for white blood cells

leukocytes

what are white blood cells

-usually larger than red blood cells

-nucleated

-lack hemoglobin

-fight infection and provide immunity

white blood cells are divided and based on structure in what two groups

granular and agranular leukocytes

what are granular leukocytes

have visible granules containing enzymes and proteins

what are the enzymes and proteins in granular leukocytes

neutrophils, basophils, and eosinophils

what are neutrophils

most abundant, phagocytize bacteria

what are basophils

granules stain deep blue, release histamine

what are eosinophils

stain deep red, fight parasitic worms

what are agranular leukocytes

lack visible granules and typically have kidney-shaped or spherical nucleus

what are monocytes

largest white blood cells; differentiate into dendritic cells and macrophages

what are dendritic cells

phagocytic cells that capture microbes with dendrites, then stimulate other white blood cells for defense

what are macrophages

phagocytes in liver, kidney, and spleen

what are the two types of lymphocytes

B lymphocytes (B cells) and T lymphocytes (T cells)

what to B lymphocytes (B cells) do

produce antibodies

what to T lymphocytes (T cells) do

kill other cells (cytotoxic T cells) or regulate responses of other cells (helper T cells)

If the number of any type of white blood cell increases or decreases beyond normal, what may it indicate

the presence of disease

what does bacterial infections mean

neutrophils are elevated w

what does infectious mononucleosis mean

B cells are elevated

what does AIDS mean

T cells levels are decreased

what does leukemia mean

abnormal white blood cells

what is another name for platelets

Thrombocytes

platelets form as a result of what

fragmentation of megakaryocytes in the red bone marrow.

what are platelets

involved in the process of clotting or coagulation

at least 12 clotting factors participate with platelets in forming a blood clot

when does the clotting process begin

when a blood vessel is damaged

how does the blood clotting process work

-blood vessel is damaged

-platelets clump and partially seal the leak

-prothrombin activator is released

-converts prothrombin to thrombin

-thrombin converts fibrinogen to fibrin

-as damage heals, the enzyme plasmin breaks down the clot

what does hemophilia refer to

a group of inherited disorders caused by deficiency in a clotting factor

what is the most common type of hemophilia

Hemophilia A, found especially in males

how is hemophilia treated

blood infusions and injections of clotting factors

what is a stem cell capable of doing

dividing and producing new cells that can differentiate into particular cell types

most exchanges between the blood and the tissues of the body take place via what?

capillaries

what is interstitial fluid

the fluid between the body’s cells and forms from the substances that left the capillaries

what is interstitial fluid that is contained within the lymphatic vessels called

lymph

what is the myocardium

major portion of the heart

consists mainly of cardiac muscle

what is the pericardium

serous membrane that surrounds the heart

what is the endocardium

lines the inner surface of the heart

membrane consisting of connective tissue and endothelium

what separates the right and left sides of the heart

a wall called a septum

what are the 4 chambers of the heart

two atria and two ventricles

what are the atria

thin walled; pump blood to the ventricles

what are the ventricles

thick walled; pump blood to the lungs and body

what are the four valves in the heart that prevent backflow

two atrioventricular valves and two semilunar valves

what are atrioventricular valves

Valves located between the atria and ventricles that regulate blood flow and prevent backflow into the atria. Supported by fibrous chordae tendinea

what is the AV valve on the right

the tricuspid valve

what is the AV valve on the left

the bicuspid valve or the mitral valve

what are semilunar valves

valves located between ventricles and major arteries

where is the pulmonary semilunar valve located

located between the right ventricle and the pulmonary artery.

where is the aortic semilunar valve

located between the left ventricle and the aorta

what is the path of blood through the heart

vena cava; right atrium; tricuspid valve; right ventricle; pulmonary semilunar valve; pulmonary trunk; pulmonary arteries; lungs; pulmonary veins; left atrium; mitral valve; left ventricle; aortic semilunar valve; aorta; body

blood must travel through what organ to go from the right side of the heart to the left side

the lungs

the right ventricle sends what type of blood into the pulmonary circuit

oxygen poor blood

the left ventricle sends oxygen rich blood to where

the rest of the body

what is cardiac output

the volume of blood pumped by the left ventricle per minute

what is a pulse

a wave effect that passes down the walls of arteries when the aorta expands and then recoils with each ventricular contraction

each heartbeat is a what

a cardiac cycle

what is the sequence of a cardiac cycle

1. the 2 atria contract simultaneously

2. the 2 ventricles contract simultaneously

3. all chambers relax

what is systole

contraction of the heart muscle

what is diastole

relaxation of the heart muscle

how many times does the heart contract/beat per minute

70 time/beats per minute

what is a heart murmur

a swishing sound; may be result of a leaky valve

what does the “lub-dub” sound of a heartbeat mean

the “lub” sound is the atrioventricular valves closing

the “dub” sound is the semilunar valves closing

the rhythmic contraction of the aorta and ventricles is due to the what

the intrinsic conduction system

how is the intrinsic conduction system made possible

by nodal tissue, which has both muscular and nervous characteristics