Chapter 40: The Circulatory System

True or false: like unicellular organisms, most multicellular organisms obtain food and oxygen, and remove waste via diffusion

false

unicellular organisms obtain food and oxygen, and remove waste via diffusion—which is difficult for multicellular organisms to do

true or false: small/simple organisms, such as flatworms, dont need a circulatory system because they’re thin and small enough for diffusion to occur

true

in this type of circulatory system, oxygen, nutrients, and hormones flow through cavities, which limits their transportation throughout the body

open circulatory system

in this type of circulatory system, oxygen, nutrients, and hormones flow within blood vessels, which efficiently transports them throughout the body

closed circulatory system

this specialized connective tissue is composed of plasma and various cellular components

blood

water, electrolytes, proteins, hormones, nutrients, gases, and wastes make up which component of blood?

plasma

you can measure the proportions of cellular components in blood via ___

hematocrit (centrifusion)

tubes that carry blood between the heart and rest of the body are known as ___

blood vessels

true or false: the heart is a contracting pump that pushes blood into muscles

false. the heart is a contracting pump that pushes blood into arteries

this type of blood cells transports oxygen and carbon dioxide, and lack a nucleus and most organelles

erythrocytes (RBC)

true or false: erythrocytes contain copper

false

erythrocytes contain hemoglobin

this hormone regulates the production of erythrocytes

erythropoietin (EPO)

“low oxygen levels → EPO released by kidney cells → RBC matures → oxygen levels increases → EPO production ceases” describes what kind of feedback loop?

negative feedback loop

this type of blood cells protects the body from infection and regulates the inflammatory reaction

leukocytes (WBC)

neutrophils, eosinophils, and basophils have vesicles that release chemicals. thus, they’re classified as what type of leukocytes?

granular leukocytes

lymphocytes and monocytes lack vesicles that release chemicals. thus, they’re classified as what type of leukocytes?

agranular leukocytes

platelets are essential for blood clotting and are formed from pieces of what cells?

megakaryocytes

platelets help in the process of forming clots to stop bleeding, which is also referred to as ___

hemostasis

during hemostasis, blood vessels constrict to reduce blood flow. this step is also known as ___

vascular spasm (step 1)

during hemostasis, platelets stick together to seal ruptured blood vessels. this step is also known as ___

platelet plug formation (step 2)

during hemostasis, blood forms into a gel to create a clot to trap erythrocytes and platelets. this step is also known as ___

coagulation (step 3)

this type of blood vessel carries blood away from the heart, and diverges into smaller vessels called arterioles

arteries

arteries are made of how many layers to carry blood away under enormous pressure?

three thick-walled layers

true or false: arterioles lack connective tissue, and have a thin smooth muscle layer

true

this type of blood vessel exchanges solutes and water with body cells, and converges into vessels called venules

capillaries

true or false: capillaries are nonporous and found everywhere in the body

false

capillaries are porous and found everywhere in the body

capillaries are made of a microscopic, thick walled layer of what type of cells to allow for material exchange via diffusion?

epithelial cells

rings of smooth muscle that regulate blood flow through capillary beds

precapillary sphincters

what type of vessels transport fluid from the cell via capillaries containing carbon dioxide and waste

lymphatic vessels

what type of fluid is screened for bacteria by lymphatic vessels and send back into the body

lymphatic fluid

this type of blood vessel returns blood to the heart via skeletal muscle contraction and gravity and acts as a blood reservoir

veins

the heart is surrounded by a fibrous sac made of three layers. this structure is called the ___

pericardium

the thin outer layer of epithelial and connective tissue of the pericardium is called the ___

epicardium

the thick middle layer of muscle of the pericardium is called the ___

myocardium

the thin inner layer of epithelial tissue of the pericardium is called the ___

endocardium

the heart is separated into 4 chambers, which are called ___

the left and right atrium, and the left and right ventricles

what muscular partition separates the right and left sides of the heart?

the septum

true or false: blood moves bidirectionally

false

blood must go in one direction, so valves prevent back flow

deoxygenated blood moves from a muscle into the right atrium via the ___

vena cava vein

the right atrium is separated from the right ventricle by the ___

right atrialventricular valve

deoxygenated blood moves from the right ventricle to the lungs via the ___

pulmonary artery

the right ventricle is separated from the pulmonary artery by the ___

pulmonary valve

in the lungs, what is added to the blood once carbon dioxide is removed?

oxygen

oxygenated blood is moved from the lungs to the left atrium via the ___

pulmonary vein

oxygenated blood moves from the left atrium to the ___

left ventricle

the left atrium is separated from the left ventricle by the ___

left atrialventricular valve

the left ventricle moves the blood toward a body system, thus organs and muscles via the ___

aorta artery

the aorta artery is separated from the left ventricle by the ___

aortic valve

how many times does blood pass through the heart?

twice

what type of blood passes through the right side of the heart?

deoxygenated blood

what type of blood passes through the left side of the heart?

oxygenated blood

true or false: the heart pumps blood through two circuits

true

the lungs, pulmonary artery, and pulmonary vein make up which circuit?

the pulmonary circuit

the rest of the body, aorta, and vena cava make up which circuit?

the systemic circuit

the complete cycle of events in the heart, for the beginning of one heartbeat to the beginning of the next heartbeat describes what cycle?

the cardiac cycle

the period of relaxation in the cardiac cycle is known as ___

diastole

the period of contraction in the cardiac cycle is known as ___

systole

during the cardiac cycle, both atria contract, forcing blood into the ventricles. this is also known as ___

atrial systole (step 1)

true or false: during atrial systole, both atrialventricular valves are open while the pulmonary and aortic valves are closed

true

during the cardiac cycle, both ventricles contract, causing the atrialventricular valves to close while the pulmonary and aortic valves open to allow blood in. this is also known as ___

ventricular systole (step 2)

during the cardiac cycle, both ventricles relax and passively fill with blood through the atrialventricular valves. this is also known as ___

diastole (step 3)

true or false: during diastole, the pulmonary and aortic valves are open, and both atria remain contracted

false. during diastole, the pulmonary and aortic valves are closed, and both atria remain relaxed

true or false: the cardiac muscle is unique because it creates its own action potentials

true

how are hearts classified among vertebrates?

how heartbeats are initiated, and the number of chambers

true or false: vertebrates have multi-chambered hearts

true

fish use gills for gas exchange, and have how many chambers in their heart?

2 chambers

amphibians and reptiles have 1 ventricle and 2 atria in what type of chambered heart?

3 chambered heart