HUMANBIOLOGY_TWENTYSEVEN

circulatory system

organ system consisting of the heart and vessels that distribute blood (or a comparable fluid) throughout the body

heart

muscular organ that pumps blood (or a comparable fluid) throughout the body

blood

type of connective tissue consisting of cells and platelets suspended in a liquid matrix

plasma

watery, protein-rich fluid that forms the matrix of blood

red blood cell

disk-shaped blood cell that contains hemoglobin

hemoglobin

pigment that carries O₂ in red blood cells

white blood cell

one of five types of blood cells that participate in the immune response

platelet

cell fragment that orchestrates clotting in blood

blood clot

plug of solidified blood

artery

vessel that carries blood away from the heart

arteriole

small artery

capillary

tiny blood vessel that connects an arteriole with a venule

venule

small vein

vein (animal)

vessel that returns blood to the heart

cardiac muscle tissue

involuntary muscle tissue composed of branched, striated, single-nucleated contractile cells

pulmonary artery

artery that leads from the right ventricle to the lungs

sinoatrial (SA) node

specialized cardiac muscle cells that set the tempo of the heartbeat; the pacemaker

cardiac output

the volume of blood that the heart pumps each minute

blood pressure

force that blood exerts against blood vessel walls

respiratory system

organ system consisting of the lungs or comparable organs that acquire O₂ and release CO₂

nose

organ that forms the entrance to the nasal cavity inside the head; functions in breathing and the sense of smell

trachea

the respiratory tube that connects the larynx to the bronchi; the “windpipe”

bronchiole

small branched airway that connects bronchi to alveoli

The ______ system transports gases and nutrients throughout the body within a fluid called ______.

circulatory; blood

Plasma is the ______. 

liquid portion of the blood and is composed of about 90% water

Red blood cells are packed with an oxygen-carrying pigment protein called ______.

hemoglobin

A component of blood called _______ blood cells are called leukocytes and participate in immune responses.

white

Blood clotting is initiated by ______. 

platelets

What is the main fluid that transports substances within the vertebrate circulatory system?

blood

What component of blood exchanges nutrients, gases, and other dissolved substances with the interstitial fluid?

plasma

Hemoglobin is the protein found in ______ blood cells that transports ______ throughout the circulatory system.

red; oxygen

Leukocytes are ______, which originate in the red bone marrow, have nuclei, and lack hemoglobin.

white blood cells

The wall of the heart consists mostly of a thick layer of ______ muscle.

cardiac

Small, colorless cell fragments that initiate blood clotting are called ________.

platelets

In humans, oxygen-depleted blood leaves the ______ side of the heart and travels to the lungs to pick up oxygen. Oxygenated blood enters the ______ side of the heart and travels to the rest of the body.

right ventricle; left atrium

The ______ node of the heart is a region of specialized muscle cells in the upper wall of the right atrium, which is sometimes called the pacemaker because it sets the tempo of the beat.

sinoatrial

Regular exercise can provide cardiovascular benefits, such as lowering ______.

blood pressure and blood cholesterol

Networks of tiny blood vessels that connect arterioles to venules are called ______ beds.

capillary

What is the name of the type of muscle that makes up the walls of the heart?

cardiac muscle

What describes blood pressure?

the force that blood exerts on the walls of arteries

The organ system that exchanges gases with the environment in most animals is called the ______ system.

respiratory

What region of specialized cardiac muscle cells causes the atria to contract and sets the tempo of the heartbeat?

sinoatrial node

Select all the components of the human upper respiratory tract?

nose; pharynx, larynx

As a result of regular exercise, the heart will strengthen and the ______ will increase, such that the heart can beat less times per minute and still pump the same amount of blood.

stroke volume.

The blood vessels in capillary beds are tiny but very numerous, which provides ______ for the exchange of materials between the blood and interstitial fluid.

more surface area

The trachea and the lungs comprise the ______ respiratory tract.

lower

The force that blood exerts on ______ is referred to as blood pressure.

vessel walls

Air flows into the lungs when the size of the chest cavity ______ and the air pressure inside the lungs is ______ than the pressure outside the body. Air flows out of the lungs when the diaphragm and chest muscles relax, and pressure inside the lungs is ______ than the air pressure outside the lungs.

increases; lower; greater

Organs of the ______ system, such as gills or lungs, allow gases from the environment to be exchanged with blood vessels from the circulatory system.

respiratory

How does oxygen cross capillary walls?

diffusion

What component of blood transports 99% of the oxygen picked up in the lungs?

red blood cells

How does carbon dioxide move into the blood?

diffusion

Red blood cells contain ______, which binds to ______ in the alveolar capillaries.

hemoglobin; oxygen

During exhalation in humans, the diaphragm and muscles of the rib cage ______, the elastic tissues of the lungs recoil, air pressure in the lungs then exceeds atmospheric pressure, and air flows ______.

relax; out of the lungs