Chapter 9 - Transport in animals Flashcards
Name the four nutrients that the cytoplasm carries
- amino acids
- glucose
- oxygen
- carbon dioxide
What do animal cells look like?
circular shaped, cell membrane, cytoplasm wth a small vacuole and a nucleus
What are the 3 characteristics of the circulatory system?
- system of blood vessels that carry blood
- heart pumps blood
- valves ensure flow in one direction
Where does oxygen blood come from
the lungs (left side)
Explain the term ‘double circulatory system’
blood passes through the heart twice in one complete body circuit
Where can double circulatory systems be found?
mammals, birds and reptiles
What are the 2 parts of the double circulatory system?
pulmonary system: vessels take blood to lungs and back
systematic system: vessels that take blood to the rest of the body and back
What kind of circulatory system do fish have?
single circulatory system
What are the negatives of a single circulatory system?
- when blood flows through tiny vessels, it loses pressure
- blood get to organs slower than mammals
What are the positives of a single circulatory system?
- needs less energy
- more efficient for getting energy to cells quickly for respiration
- blood goes back to the heart to increase pressure
How many chambers does the heart have?
4
What happens in the aria (upper heart chambers) ?
blood flows
What happens in the ventricles (lower heart chambers) ?
pumps blood out
Define septum
the structure by which the left and right side of the heart are divided
How does the blood enter the heart?
Left atrium receives oxygenated blood through pulmonary vein which came from lungs. Right atrium receives deoxygenated blood from the rest of the body through the venae cavae.
Why do the strong muscles in the walls of the ventricle contract?
to pump blood out of the heart
Define aorta
largest artery in the body. recieves oxygenated blood from left ventricles and pumps it to the rest of the body (away from the heart)
Define pulmonary artery
carries deoxygenated blood from the right ventricle to the lungs (to heart)
What are the 6 characteristics of red blood cells?
- approximately 84% of the cells in the human body (20-30 trillion
- full circulation takes around 1 minute
- delivers oxygen to every tissue in the body
- live up to 120 days, then get recycled
- no nuclei to help carry oxygen (disk with a large surface area)
- small so they can squeeze through tiny capilaries
Define atrioventricular valve
valve between atrium and ventricle in heart that allows blood to flow from atria to ventricles
What do valves prevent?
the backflow of blood
Define semi-lunar valves
close to entrance of aorta and pulmonary artery that prevents backflow of blood from the arteries back into ventricle
Which has thicker wall; ventricles or atria?
ventricle
Which side of the ventricles have thicker walls?
left
What effect does pressure have on the walls of the heart chambers?
more pressure = thicker wall
Define coronary arteries
vessels that supply blood to the heart muscles on the outside of the heart
What does the heart need to continue pumping blood?
a constant supply of nutrients and oxygen
How can coronary arteries get blocked?
if cholesterol builds up
What happens if blood clots form?
the lumen can get blocked more
What happens if the coronary arteries get blocked?
- the cardiac muscle cannot get any oxygen or nutrients
- muscles cannot contract, therefore the heart could stop beating
Can CHD be eliminated?
no but it can be prevented
What can be done to prevent coronaryheart disease (CHD)?
- no smoking
- regular exercise
- healthy diet
Is saturated fats linked with high colesterol?
yes
Why is a vegetarian diet healthier than a meat diet?
because meat has more saturated fats than than plant-based foods
1 heartbeat =
1 lub-dub
How fast does a normal person’s heart beat when at rest?
60 - 75 times per minute
Sound of a heart beating =
opening and closing the valves
Define pulse
expansion and relaxation of an artery caused by the heart pushing blood through it
pulse rate =
heart rate
How is heart activity studied in hospitals?
electrocardiograms (ECG)
Define ECG
a graph showing the electrical activity of a heart plotted over time
What are the 4 components of the blood?
- red blood cells
- white blood cells
- platlets
- plasma
What does the cytoplasm in red blood cells contain?
haemoglobin
Define haemoglobin
a red pigment that contains iron that combines with oxygen in the lungs
What is the function of oxyhaemoglobin?
releases oxygen when levels are low (haemoglobin combined with oxygen)
What are the 3 characteristics of white blood cells?
- nucleus that is often large
- small but larger than red blood cells
- move around easily, can squeeze out of capillaries into all parts of the body
What is the function of white blood cells?
to fight pathogens and clean up dead body cells
What are the 2 types of white blood cells?
Phagocytes and Lymphocytes
Define phagocytes
destroy pathogens by engulfing them and digesting them (important term: phagocytosis)
Define lymphocytes
produce antibodies which fix onto pathogens and destroy them
What is the nucleus like in each type of white blood cells?
phagocytes: lobbed nucleus
lymphocytes: have a large round nucleus that fits the cell
What are the 5 characteristics of platlets?
- small fragments of cells with no nucleus
- when blood vessels break, platlets release a substance that makes fibrinogen which then changes it into insoluble fribin
- fribin forms fibres that pile up on top of each other
- clumps of platlets and red blood cells all come together to form a blood clot
- made in red bone marrow
What are the 3 characteristics of plasma?
- mostly water
-many substances dissolved in it (glucose, amino acids, mineral ions) - transports hormones (adredeline) and waste products (CO₂ and urea)
