The heart and circulation

Question 1

Function of an artery

Answer 1

To carry high pressure blood away from the heart (usually oxygenated exception being pulmonary artery)

Question 2

Function of the vein

Answer 2

To carry low pressure blood back to the heart (usually deoxygenated exception being the pulmonary vein) (deoxgenated blood still has 16% oxygen so not no deoxgen)

Question 3

Features of arteries

Answer 3

Thick muscular walls with elastic fibers to handle high pressure blood with narrow lumen to push blood through the body as far and strong as possible

Question 4

Features of veins

Answer 4

Thinner walls and wider lumen because less pressure blood
But blood is so low pressure that the veins need valves to prevent backflow

Question 5

Features of capillaries

Answer 5

Walls are one cell thick and the bring glucose and oxygen to every cell in the body because less diffusion distance helps the materials exchange more efficiently

Question 6

Main Artery

Answer 6

Aorta

Question 7

Main Vein

Answer 7

Vena Cava

Question 8

Blood vessel that brings glucose and oxygen to the heart

Answer 8

Coronary Artery (Branches out from the Aorta) allows the cardiac muscles respire

Question 9

Which side of the heart pumps blood yo the rest of the body

Answer 9

Left Ventricel(it will be on the right side of diagrams) has thicker more muscular walls

Question 10

Valves between Atrium and Ventricles

Answer 10

Atrio-ventricular valves

Question 11

Valves between Ventricles and Arteries

Answer 11

Semi lunar valves

Question 12

Where are pace maker cells that allow the heart to be myogenic (beat by itself) located

Answer 12

Walls of the right atrium

Question 13

How do single cell organisms respire

Answer 13

Since they have a high SA to volume ratio they can exchange materials directly into the environment

Question 14

How do insects respire

Answer 14

Insects need a transport system to respire but as they are quite small they only require an open circulatory system meaning their body cavity filled with blood
This wouldn’t work for larger animals as all the blood would rest in the legs because of no blood pressure and oxygenated and deoxygenated blood would mix

Question 15

How do fish respire

Answer 15

Fish are big enough that they need to ensure every cell in their body has access to glucose and oxygen.
They have a closed circulatory system meaning their blood travels through blood vessels but unlike ours its a single circulatory system as oxygen diffuses straight into the blood via gills so blood only needs pass through the heart once

Question 16

How do humans respire

Answer 16

Lungs
Humans have a closed circulatory system. A double circulatory system meaning blood passes through our hearts twice

Question 17

Red blood cells

Answer 17

Carry oxygen that combines with the haemoglobin found in the biconcave structure. Its lack of nucleus means that the surface area is increased. also the fact the diameter is about the size of a capillary means that oxygen will diffuse in or out

Question 17

Plasma

Answer 17

Liquid that carries the blood which is mostly made of water(91-92%)(a polarized substance meaning it dissolves ionic substances) It has a high specific heat capacity as it is a large lattice which helps it transfer heat from your core to the rest of you body. it being liquid also means blood can flow

Question 18

Bonding formula for Haemoglobin

Answer 18

Hb+ 4O2 ⇌ HbO8
Collects O2 in high concentration but releases in low

Question 19

Platelets

Answer 19

Create a net of dead cells that trap red blood cells which form a clot which dries and protects from infection

Question 20

white blood cells

Answer 20

Are the bodies immune system

Question 21

Types of white blood cells

Answer 21

• Phagocytes- ingest(eat) and destroy bacteria, viruses, microbes and cellular debris
• Lymphocytes (main immune system)- some produce anti bodies which remove unwanted substances while others produce ani toxins to neutralise toxins

Question 22

Functions of blood (name 3)

Answer 22

• to flow
• immune system
• heals wounds
• allows respiration
• caries around glucose amino acids and other nutrient
• caries waste such as CO2 and urea
• transports water
• transports heat
• transports hormones

Question 23

Signs of heart problems

Answer 23

• Less oxygen in glucose is transported so less respiration occurs inducing increased fatigue
• Pain in chest (that can spread to arms)
• Palpitations or general changes in rhythm
• pale or discolored extremities e.g. fingers or toes
• Sweating
• High blood pressure

Question 24

Coronary heart disease

Answer 24

When low density lipoproteins (Bad cholesterol) are deposited in the walls of the coronary arteries increasing pressure of the blood in that region which increases risk of bursting or making it that blood cannot flow to certain areas of the heart to let the cells respire either changing the way the heart beats or completely killing the cells of a certain area (fun fact: high density lipoproteins can remove fatty deposits from artery walls but only in the right doses)

Question 25

Treatments of coronary heart disease

Answer 25

Statins- that lower cholesterol without surgery but are pills you need to take for life that may have side effects hence not being the best choice for all
Stents- a mesh that manually widens the blood vessel without any major surgery and have no risk of an immune response the risks are though that it could rupture a blood vessel which could cause internal bleeding or longer term could lead to a heart attack or stroke
(stents are made of either stainless steel, cobalt chromium or platinum chromium)

Question 26

Heart valve disease

Answer 26

If the valves don’t work properly then blood can flow backwards and blood flow from the heart becomes inconsistent- it is possible to replace the valves

Question 27

Artificial valves

Answer 27

• Biological are quieter and have no risk of clotting but only last 8-10 years
• Mechanical last over 20 years but can clot and are louder