Bio - Chapter 21

Question 1

Artery

Answer 1

Carries blood from heart to organ

Question 2

Arteriole

Answer 2

Carries blood from an artery to a capillary bed

Question 3

Venule

Answer 3

Carries blood from capillaries to a vein

Question 4

Vein

Answer 4

Returns blood to the heart

Question 5

Pulmonary circuit

Answer 5

Oxygen poor blood collected by the right atrium is pumped to the right ventricle then to pulmonary arteries to the lungs
In capillaries of the lungs blood gives co2 and picks up O2
Oxygen Rich blood returns through pulmonary veins to the left atrium

Question 6

Systemic circuit

Answer 6

Oxygen rich blood collected by the left atrium is pumped from the left ventricle through the aorta to capillary beds of the body
At capillary beds in the body, blood gives up O2 and picks up CO2
The superior vena cava and inferior vena cava return to oxygen poor blood to the right atrium

Question 7

Structure of the human heart

Answer 7

Pericardium protect the heart
Protects and anchors the heart
Prevents overfilling of the heart with blood
Allows for the heart to work in relatively friction free environment.
Each half of the heart has two chamber: upper atrium and lover ventricle
AV, aortic, and pulmonary valves prevent blood from moving backwards

Question 8

Major vessels of the heart

Answer 8

Vessels returning blood to the heart include: superior and inferior  vena Cana
Right and left pulmonary veins
Vessels conveying blood away from the heart: pulmonary trunk, which splits into right and left pulmonary arteries.
Ascending aorta (three branches)

Question 9

Pathway of blood through the heart and lungs

Answer 9

Right atrium - right ventricle - pulmonary arteries - lungs - pulmonary veins - left atrium - left ventricle - aorta - systemic circulation

Question 10

Cardiac cycle

Answer 10

Sequence of contraction and relaxation of heart chambers that occurs with each heartbeat.
Signals from the cardiac peacemaker trigger contraction of the atria, then the ventricles
Atria fill ventricles
Ventricles drive blood flow away from the heart
Closing heart valves cause heartbeat sounds

Question 11

Plasma

Answer 11

Fluid portion of blood, composed of water with dissolved ions and molecules
Transports gases, nutrients , wages , signaling molecules, plasma proteins.
50-60% of the total blood volume

Question 12

Red blood cells

Answer 12

Hemoglobin - filled blood cells that transport oxygen and, to a lesser extent, carbon dioxide
Lack nucleus and organelles; live about 4 months

Question 13

White blood cells (leukocytes)

Answer 13

Various kinds function in housekeeping (digest debris ) and defend against viruses, bacteria, and other pathogens

Question 14

Platelet

Answer 14

Cell fragment that patches tears in blood vessels and initiates blood clotting in response to injury
Last 5-9 days

Question 15

Capillary beds

Answer 15

Exchange materials btw blood and interstitial fluid around cells
Gases diffuse across the plasma membrane
Blood pressure at arterial ends of capillary beds causes plasma to leak out, carrying oxygen, ions and nutrients.
Osmosis at venous ends of capillary beds causes water from interstitial fluid to enter blood carrying wastes (excess fluid becomes lymph)

Question 16

Human cardiovascular system

Answer 16

The human heart has four chamber and pumps blood through two separate circuits
Pulmonary and systemic
Each circuit has a network of blood vessels that carry out between the heart and capillary beds

Question 17

Pharynx

Answer 17

Throat; opens to airways and digestive tract

Question 18

Larynx

Answer 18

Short airway containing vocal cords

Contraction of vocal cords changes the size of the glottis

Question 19

Glottis

Answer 19

Opening formed when the vocal cords relax

Question 20

Epiglottis

Answer 20

Tissue flap at the entrance to the larynx

Folds down to prevent food from entering the trachea when you swallow

Question 21

Trachea

Answer 21

Major airway leading to the lungs ; windpipe

Branches into two bronchi, each leading to a lung

Question 22

Bronchus (bronchi)

Answer 22

Airway connecting the trachea to a lung

Question 23

Bronchiole

Answer 23

Small airway leading from bronchus to alveoli

Question 24

Alveoli (alveolus)

Answer 24

Tiny, thin-walled air sacs

Site of gas exchange in the lung

Question 25

Diaphragm

Answer 25

Dome-shaped muscle at base of thoracic cavity that alters thoracic cavity size during breathing Separate thoracic cavity from abdominal cavity Of all smooth nuclear only diaphragm can be controlled voluntarily

Question 26

Exchanges at respiratory membrane

Answer 26

Blood carries gases btw lungs and body tissues Fused basement membranes of alveolar and pulmonary capillary cells from the respiratory membrane Oxygen and carbon dioxide diffuse across the respiratory membrane each following its own concentration gradient

Question 27

Oxygen transport

Answer 27

Oxygen follows its concentration gradient from alveolar air spaces into pulmonary capillaries then into red blood cells where it binds reversible with hemoglobin

Question 28

Carbon dioxide transport

Answer 28

CO2 diffuses from cells into interstitial fluid then into blood CO2 diffuses from pulmonary capillaries into air in alveoli then is expelled