Exchange Of Materials - Heart, Blood, Vessels Flashcards
Our body needs to pump blood to…
- get oxygen to ourselves
- move nutrients
- move waste
- move hormones
- help fight disease
- help stabalise body temperature
We need a … System because diffusion isn’t efficient enough for our whole body
Circulatory
Name the three components of the circulatory system
Heart - the pump
Blood - transport medium
Blood vessels - transport route
What do veins do
Gets the blood back to the heart
What do arteries do
Gets blood taken away from the heart
Label the right and left sides of a heart
Workbook
The left side of the heart has a … Muscular wall because it has to pump the blood …
Thicker
Further
List the circulatory system in order from the lungs
Lungs - pulmonary vein - heart (left atrium, valve, left ventricle, valve) - aorta - body (hepatic artery, hepatic portal vein, renal artery, renal vein, hepatic vein) - vena cava from both enter points - heart (both entering points meet in the middle at the right atrium, valve, right ventricle, valve) - pulmonary artery - lungs
Pulmonary circulation
Transports blood to and from the lungs to exchange O2 and CO2 with air
Systematic circulation
Transports blood to and from the body to exchange O2 and CO2 with body cells
Aorta
Carries blood from heart to the body (oxygenated)
Pulmonary vein
Carries blood from lungs to heart (oxygenated)
Vena cava
Carries deoxygenated blood through the heart from the body
How blood flows through the heart
Diastole: heart muscle completely relaxed, blood flows into atria
Atrial system: atrial contract, AV valves open, blood flows into ventricles
Ventricular systole: ventricles contract, AV valves closed, blood flows out of ventricles
Pulmonary artery
Carries the blood from the heart to the lungs (deoxygenated)
Heart rate
Beats per minute
Stroke volume
Volume of blood pumped per beat
Effects exercise has on the heart
- increases heart rate
- muscles need more energy
- rate of respiration increases
- more oxygen and glucose needed
- heart rate and force of beat increase
Effects stress has on the heart
- increases heart rate
- fight or flight response
- adrenaline causes heart to beat faster
4 ways the body controls heart rate
- osmoreceptors in the aorta sense CO2 levels
- cardiac centre in the medulla (part of brain) receives information via sensory nerve
- cardiac centre sends nerve impulses via accelerator or decelerator nerves
- pacemaker reacts and increases/decreases heart rate and force of heart beat therefore blood pressure increases/decreases
Effects of adrenalin on heart rate
Adrenaline released from the adrenal glands stimulates the pacemaker to increase heart rate
Coronary heart disease
- blockage of coronary artery
- blood supply to area of heart muscle cut off
- less O2 and glucose reaches heart muscle
- area of heart muscle cannot respire leading to a heart attack (angina)
Artery
- heart to organs
- high blood pressure
- arterial blood (red)
- small lumen lining
- thick wall with muscle fibres and elastic tissue
- no valves
Vein
- organs to heart
- low blood pressure
- venous blood (deep purple/blue)
- large lumen lining
- thin wall with little muscle and elastic tissue
- with valves
Capillary
- carry blood through organs
- medium blood pressure
- thin walls
- very small lumen lining (single file)
- no valves
Capillaries take away waste materials from body cells, how
Artery - capillary puts O2 and glucose into cell - capillary takes away urea and CO2 from cells - vein
Why do veins have valves
To prevent back flow
Why are capillaries walls only 1 cell layer thick
In order to let diffusion to occur fast
Why do arteries have muscular walls
To maintain high blood pressure
What is the main function of the placenta in the womb
To provide oxygen and nutrients to the foetus and remove waste products like CO2
How does oxygen pass from the mother to the baby
O2 is absorbed from the intervillous space
Blood arrives via the endometrial arteries
What other functions does the placenta have
It provides a stable connection with the mother and produces hormones which stop menstruation
Why is it important that the mother and foetus’ blood supply don’t mix
The mothers blood may have bacteria or viruses which could harm the baby
Why is a pregnant woman smoking dangerous
As carbon monoxide can reach the developing foetus thus the foetus has less oxygen to grow
Composition of blood
Plasma (55%)
White blood cells
Red blood cells
Plasma ingredients/function
- to transport substances around the blood
- water(80%)
- glucose
- amino acids
- CO2
- urea
- proteins (antibodies, hormones, clotting factors)
Leukocytes (white blood cells)
- phagocytes (ingest pathogens)
- lymphocytes (produce antibodies)
Platelets (thrombocytes)
Involves in blood clotting
Erythrocytes (red blood cells)
- haemoglobin (transport of oxygen and haemoglobin [oxyhaemoglobin])
- no nucleus (more space for haemoglobin)
- biconcave shape (large SAV and short diffusion distance)
- thin membrane (short diffusion distance)
Sickle cell anaemia
Inherited condition
Prevents carrying of oxygen
Harmophilia
Blood doesn’t clot properly
Lose more blood
