Transport in animals Details Flashcards
(43 cards)
Features of double circulation
-Oxygenated blood is pumped at high pressure to the cells of the body
-Deoxygenated blood is pumped at low pressure
-No mixing of oxygenated and deoxygenated blood
-Blood flows at both high and low pressure
-Contain valves to prevent the backflow of blood
Reasons for oxygenated blood being pumped at high pressure to the cells of the body
allows for rapid blood flow to cells and removal of waste products
Reasons for deoxygenated blood being pumped at low pressure
to protect the lungs
Features of single circulation
-Gills slow down the blood flow
-Blood flows at just low pressure
-Oxygen is received at low pressure and brought to cells of the body
-Contain valves to prevent the backflow of blood
Advantages of double circulation over single circulation
-Ensures efficient supply of oxygen to body
-Ensures efficient supply of(named) nutrients to body
-No mixing of oxygenated and deoxygenated blood
-Helps to maintain a high rate of respiration
-Allows more time for gas exchange
Features of arteries
-Large blood vessels that carry blood at high pressure
-Carry blood from your heart to the rest of your body
-Blood is rich in oxygen and nutrients
-As arteries get further away from heart, they begin to branch, becoming smaller and smaller
Features of capillaries
-Where oxygen is transferred to your tissues
-Wastes from cells are transferred into the blood from here
Features of veins
-Lead back to the heart
-Carry deoxygenated blood back to heart
Structure of arteries
-Thick outer wall(to withstand blood being carried at high pressures)
-Small lumen(expands as blood pulsates through to maintain blood pressure)
-Thick layer of elastic tissue(helps deal with high pressure)
-(NB: Valves absent since high pressures prevent backflow)
Structure of veins
-Large lumen(to reduce blood flow resistance)
-Thin layer of elastic tissue
-Thin outer wall(since blood is transported at low pressure)
-Contains valves(to prevent backflow)
Structure of capillaries
-Very small lumen
-Wall one cell thick(allows for quick diffusion of nutrients/wastes)
-Site of gas exchange
Process of blood circulation
-Deoxygenated blood enters right atrium(through vena cava)
-Deoxygenated blood enters right ventricle
-Deoxygenated blood is pumped by right ventricle(through pulmonary artery) to lungs where they become oxygenated
-Oxygenated blood enters left atrium(through pulmonary vein)
-Oxygenated blood enters left ventricle
-Oxygenated blood is pumped by left ventricle to rest of the body(through the aorta)
-Body cells use oxygen, causing blood to become deoxygenated
-Deoxygenated blood returns to heart(and cycle repeats)
In the arteries, blood is pumped…
away from the heart
In the veins, blood is pumped…
to the heart
Ways to monitor the activity of the heart
-ECGs(Electrographs)
-Pulse rate
-Listening to the sounds of the valves closing
(In terms of heart rate)physical activity…
increases the heart rate
Cause of coronary heart disease
Consuming too much fat
Why physical activity increases the heart rate
-Increased energy demand in muscles
-Increased rate of respiration(since blood must travel to quicker to the muscles to supply them with oxygen/nutrients while also removing waste products(eg. carbon dioxide)
-Heart rate increases to meet demands
Possible risk factors of coronary heart disease
-Being male:(
-High-cholesterol diet
-Lack of exercise
-Stress
-Smoking
-Genetic predisposition
-Age(greater chance if you’re older)
Cause of coronary heart disease(coronary artery perspective)
Heart’s blood supply being blocked by a build-up of fatty substances in the coronary arteries
Function of the right/left atrium
Contracts to pump blood into the right/left ventricles(respectively)
Function of right ventricle
Contracts to pump blood to the lungs(to become oxygenated)
Function of the left ventricle
Contracts to pump blood to the rest of the body
Function of atrioventricular valves
Prevent the backflow of blood and separate the atrium and the ventricles
