Unit D: The Circulatory System

Question 1

3 key roles of the circulatory system

Answer 1

Transport gases, nutrients, waste products (throughout body)
Regulate temperature and distribution of hormones
Protect body against disease
Transports: nutrients, oxygen, waste, heat, hormones, immune cells
Contains heart, blood and blood vessels

Question 2

Where is cardiac muscle found

Answer 2

in the heart

Question 3

What kind of system is the cardiac muscle

Answer 3

autonomic nervous system (medulla oblongata)

Question 4

Type of system that smooth muscle is

Answer 4

automatic nervous system

Question 5

Location of smooth muscle:

Answer 5

found in the lining of organs
Ex. stomach, esophagus, uterus

Question 6

Location of skeletal muscle

Answer 6

attached to bones

Question 7

What kind of system is found in the skeletal muscle?

Answer 7

systematic nervous system
(voluntary)

Question 8

What happens in the skeletal muscle when there is a nerve impulse
(what happens to the muscle and what does it stimulate?)

Answer 8

Muscles contract
- stimulates the release of calcium ions in muscle fibres

Question 9

With is triggered after the release of calcium ions?

Answer 9

Actin and myosin filaments slide over one another

Question 10

What happens to the muscles when the actin and myosin filaments slide over one another

Answer 10

Muscle fibres shorten and contract
- After the contration, actin and myosen disengage

Question 11

What happens when actin and myosin (muscle fibres) disengage?

Answer 11

muscles relax/elongate, and go back to normal

Question 12

What is the autonomic (involuntary) nervous system?

Answer 12

network of nerves thouhgout the body that control unconscious processes (w/o thinking about them) → chemoreceptors in the medulla oblongata
Ex. breathing, heart beat

Question 13

What is the systematic (voluntary) nervous system?

Answer 13

a part of the peripheral nervous system (voluntary control of body movements) → responsible for all functions that can be consciously influenced → skeletal muscles in the body
Ex. moving our arms, legs, etc.

Question 14

What are Type 1 fibres? (type of respiration, efficiency)

Answer 14

• slower muscle twitch
• gets energy/fuel from aerobic respiration
• typically found in higher abundance in long-distance runners
• Slow but efficient

Question 15

What are Type 2 fibres? (type of respiration, efficiency)

Answer 15

• faster muscle twitch
• fuelled by anaerobic respiration
• typically found in higher abundance in sprinters
• fast but inefficient

Question 16

How many chambers are there in the heart? (what are they)

Answer 16

4 Chambers
2 atria (top)
2 ventricles (bottom)

Question 17

What is the purpose of valves?

Answer 17

Ensure blood flows only in one direction
Ensures correct direction through hearts chambers → body

Question 18

What is the purpose of the aorta?

Answer 18

arries blood AWAY from heart → body (leaves through *aortic valve)
To arteries: Devlivers oxygenated blood to brain, muscles and other cells

Question 19

What is the purpose of the superior/inferior vena cava?

Answer 19

Both: carry oxygen-poor blood to heart’s right atrium → right ventricle → lungs (using pulmonary artery)
Purpose: brings deoxygenated and trades in carbon dioxide for oxygen

Question 20

Where does the blood go in the superior vena cava?

Answer 20

carries blood from head, neck, arms and chest

Question 21

Where does the blood go in the inferior vena cava?

Answer 21

carries blood from legs, feet and rogans in abdomen/pelvis

Question 22

What is the purpose of the pulmonary arteries?

Answer 22

carries deoxygenated blood from right ventricle → lungs

Question 23

What is the purpose of the pulmonary veins?

Answer 23

carry oxygenated blood from lungs to the left atrium
- so blood can be pumped to the rest of the body

Question 24

What is the purpose of the left atrium?

Answer 24

holding chamber for oxygen-rich blood (from lungs and is pumped → left ventricle)

Question 25

What is the purpose of the left ventricle?

Answer 25

pump oxygen-rich blood from lungs → body LEFT atrium and ventricle handle OXYGENATED blood

Question 26

Why is the left ventricle bigger than the right?

Answer 26

Why is it bigger?: has to pump blood → whole body (needs enough pressure)

Question 27

What is the purpose of the right atrium?

Answer 27

receives oxygen-poor blood from body and pumps to right ventricle

Question 28

What is the purpose of the right ventricle?

Answer 28

pumps oxygen-poor blood → lungs RIGHT atrium and ventricle handle DEOXYGENATED blood

Question 29

What is the purpose of the septum?

Answer 29

separates the left and right sides of the heart (wall of tissue) Purpose: prevents the oxygenated blood from mixing with the deoxygenated Muscle in left ventricle = thicker This is b/c the left ventricle pumps blood to the whole body and needs strength to do so Right ventricle = only to lungs Hole in septum = less oxygenated blood for body

Question 30

What is the difference between the Capillaries, Arteries and the Veins

Answer 30

Capillaries: embedded in the heart wall Arteries: carry blood AWAY from the heart Veins: carry blood TO the heart

Question 31

What does the pulmonary pathway do?

Answer 31

circulates blood from the heart → lungs and back

Question 32

What does the systematic pathway do?

Answer 32

circulates blood from heart → body and back

Question 33

What does the coronary Pathway do?

Answer 33

Oxygen/nutrients delivered → heart (through *capillaries) Purpose: carries deoxygenated blood away Supplied by 2 small arteries (branch off of aorta) Left and right coronary arteries Cardiac tissue needs oxygenated blood to pump blood (working heart) 4 coronary arteries (blocked → risk of heart not pumping properly)

Question 34

What is the path of blood flow through the heart? (high carbon dioxide concentration vs the oxygenated)

Answer 34

Depleted oxygen blood → right atrium (entry through superior/inferior vena cava) Blood moves through right atrium → right ventricle → out of the heart (through pulmonary arteries) → lungs Oxygenated blood = back to heart and enters left atrium (through pulmonary veins) Blood flows → left ventricle → out of heart (through aorta) → body

Question 35

What is the Sinoatrial Node and what does it do to contribute to the beating of the heart?

Answer 35

generates an electrical signal that causes the upper heart chambers (atria) to contract Natural pacemaker initiating the sinus rhythm by electrical signals Location: right atrium ensures a coordinated contraction between atria and ventricles (by signals and pauses) Stimulated by brain Generates electrical impulses resulting in…

Question 36

What is the purpose of the contraction of the atria? (contribution to the beating heart)

Answer 36

reservoirs for blood between contractions Upper chambers Contractions separate the right and left heart as 2 separate circuits Purpose: receives blood returning to heart from body Signals the…

Question 37

What is the purpose of the atrioventricular node?

Answer 37

to relay electrical impulses from atria (upper chambers) → ventricles (lower chambers) “Gatekeeper” Connects the electrical systems of the atria and ventricles Transmits signals to ensure coordinated heartbeats Introduces a delay before passing the signal → ventricles (allowing atria to contract completely and push blood → ventricles before they contract)