The heart and circulation Flashcards
Function of an artery
To carry high pressure blood away from the heart (usually oxygenated exception being pulmonary artery)
Function of the vein
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)
Features of arteries
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
Features of veins
Thinner walls and wider lumen because less pressure blood
But blood is so low pressure that the veins need valves to prevent backflow
Features of capillaries
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
Main Artery
Aorta
Main Vein
Vena Cava
Blood vessel that brings glucose and oxygen to the heart
Coronary Artery (Branches out from the Aorta) allows the cardiac muscles respire
Which side of the heart pumps blood yo the rest of the body
Left Ventricel(it will be on the right side of diagrams) has thicker more muscular walls
Valves between Atrium and Ventricles
Atrio-ventricular valves
Valves between Ventricles and Arteries
Semi lunar valves
Where are pace maker cells that allow the heart to be myogenic (beat by itself) located
Walls of the right atrium
How do single cell organisms respire
Since they have a high SA to volume ratio they can exchange materials directly into the environment
How do insects respire
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
How do fish respire
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
How do humans respire
Lungs
Humans have a closed circulatory system. A double circulatory system meaning blood passes through our hearts twice
Red blood cells
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
Plasma
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
Bonding formula for Haemoglobin
Hb+ 4O2 ⇌ HbO8
Collects O2 in high concentration but releases in low
Platelets
Create a net of dead cells that trap red blood cells which form a clot which dries and protects from infection
white blood cells
Are the bodies immune system
Types of white blood cells
- 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
Functions of blood (name 3)
- 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
Signs of heart problems
- 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