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Biology MC Questions

Hey there,
I have some questions on my biology quiz I wasn't sure about and can find no answer to. Could someone give me the correct answers to these as well as explanations for them?

Which is not a correct statement about phagocytes?

•

a. They provide specific defence against disease-causing organisms.

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b. They have many mitochondria to produce ATP for endocytosis.

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c. They are white blood cells with a lobed nucleus.

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d. They have many lysosomes containing hydrolytic enzymes.



Aortic stenosis is a heart valve disorder in which the aortic semi-lunar valve opening is narrow. Which effect could aortic stenosis have on the heart structure and function?

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a. The wall of the left ventricle thickens, leading to an enlarged heart and inability to relax and fill completely during diastole.

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b. The cardiac muscle of the left ventricle wall is thinned by blood leaking out of the left ventricle during ventricular diastole.

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c. The tendons of the heart valves are weakened by blood being forced back through the bicuspid/left atrioventricular valve into the left atrium.

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d. There is less cardiac muscle in the left ventricle and reduced diastolic blood pressure, caused by the smaller blood volume entering the left atrium.

•

(My guess is A based on the research I did)



If a molecule of CO2 released into the blood in your left toe travels out of your nose, it must pass through all of the following structures except the

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a. alveolus.

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b. right ventricle.

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c. pulmonary vein.

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d. trachea.

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e. right atrium.

The graph shows the human haemoglobin dissociation curve. Which range of partial pressures of oxygen would be found in pulmonary arteries?



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a. between 6 and 8 kPa

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b. between 0 and 2 kPa

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c. between 8 and 12 kPa

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d. between 2 and 6 kPa

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(My guess is b)



Which reactions will be taking place in blood in a capillary next to an alveolus?

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a. 1 and 2

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b. 2 and 3

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c. 2 only

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d. 1 only



The Bohr effect describes the effect of

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a. decreased pH decreasing the affinity of hemoglobin for oxygen, enhancing unloading.

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b. decreased pH increasing the loading of carbon dioxide onto hemoglobin.

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c. increased pH on the increased ability of oxygen to load onto hemoglobin.

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d. increased temperature decreasing the affinity of hemoglobin for oxygen.

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(My guess is C)



The diagram shows the pressure changes in various structures of the left side of the heart during the cardiac cycle. At the end of which period, A, B, C or D, is the ventricle full of blood?



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a. A

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b. B

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c. C

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d. D


It would be a huge help if someone could help me with these. Thank you.

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I do AQA AS bio, Ill try them.
(edited 5 years ago)
q1 is d,
q2 im not sure maybe a Im not confident with heart
q3 -
q4 - pulmoary arteries carry deoxygenated blood to heart to be oxygenated at heart - honestly not sure xD,
can't do q2,3,4 XD
q5 - d - reaction 1 only
q6 - a
q7- B
Would have helped if you numbered the q's.
(edited 5 years ago)
Where did you get the q's from?
If you want explanation:
q1 - ultrastructure link to function, phagocytes need lysosomes to secrete lysosymes/hydrolytic enzymes whcich hydrolyse the pathogen it egulfed - this is a01.
Original post by Jack Smith123
q1 is d,
q2 im not sure maybe a Im not confident with heart
q3 -
q4 - pulmoary arteries carry deoxygenated blood to heart to be oxygenated at heart - honestly not sure xD,
q5 - d - reaction 1 only
q6 - a
q7- B
Would have helped if you numbered the q's.



Q1 is A....
q5- talking about loading of haemoglobin with 02 so Its either a or c, I picked a cuz Im not sure about h+ ions.
a6-a01
q7 - right before ventricular systole.
(edited 5 years ago)
In AQA I learnt phagocytosis is a non - specific response, but then again it might be because of the specific class 2 histocompatibility molecule complementary to pathogen so it would make some sense for it to be a.
Original post by ZombieTheWolf
Q1 is A....

Oooh, And it also states that the lysosomes 'contain ' the hydrolytic enzymes which may not be 100% accurate as I learnt that it secretes the lysosymes so it would make sense for it to be a
(edited 5 years ago)
Reply 8
Avatar for KMabry
KMabry
OP
1
I did some research and phagocytes are said to contain a lot of lysosomes.
I'm sorry I didn't number them, I'll fix that.
I do need some more explanation so I can be confident what I'm being told is right.
Original post by Jack Smith123
In AQA I learnt phagocytosis is a non - specific response, but then again it might be because of the specific class 2 histocompatibility molecule complementary to pathogen so it could be a.


Yes, you are correct! The question says which isn't correct, A says phagoctyes are specific so that must be the incorrect one :smile:
o.0, thought it said correct in the q xD. Never knew nucleus was lobed but might have heard of it before, why does endocytosis need atp- active transport of the pathogen against conc. grad?
Original post by ZombieTheWolf
Yes, you are correct! The question says which isn't correct, A says phagoctyes are specific so that must be the incorrect one :smile:
(edited 5 years ago)
Reply 11
Avatar for KMabry
KMabry
OP
1
what classifies the phagocytes' disease control to be 'non specific'? I didn't know what that meant.
Means the response phagocytes have for all pathogen is same - but note that it really isn't if you pay attention to detail as the phagocyte would produce a complementary class 2 histocompatibility molecule to pathogen to take its antigens to present on cell surface membrane, so it does have a specific aspect to it. But then again that's only for macrophages. Bad q xD.
Original post by KMabry
what classifies the phagocytes' disease control to be 'non specific'? I didn't know what that meant.
Reply 13
Avatar for KMabry
KMabry
OP
1
Alright, now that we've gotten that one out of the way, how about the others?
Reply 14
Avatar for KMabry
KMabry
OP
1
And these questions were randomly assigned to me on Schoology. I did some digging to find their origin, but to no avail.
First q was a heck of a q lol.
Im not confident with 2,3,4.
q5: d - Reaction 1 only. agree?
Original post by KMabry
Alright, now that we've gotten that one out of the way, how about the others?
Original post by Jack Smith123
o.0, thought it said correct in the q xD. Never knew nucleus was lobed but might have heard of it before, why does endocytosis need atp?


Honestly, I'm crappy in this area of biology but this is why I think so:
Think about cell membranes. When you take something in passively, it's usually non-polar and small such as Oxygen. Many passively taken molecules usually work down a concentration gradient too and don't usally require the cell itself to do anything.
Big or charged molecules usually require energy provided by ATP to enter the membrane.

Now think about a phagocyte taking in something much much bigger, perhaps bacteria. The cell here is taking in the bacteria, the bacteria isn't choosing to enter the phagocyte.
It isn't about the size of the molecule but the concentration gradient it is moving against and the type of molecule it is because this will affect what process it will take to move across the cell surface membrane. E.g the pathogen will require atp as there will be low conc. of pathogen inside the phagocyte and high conc of pathogen outside the phagocyte so active transport will have to occur hence mitochondria required to produce atp for endocytosis of the pathogen, right?

Original post by ZombieTheWolf
Honestly, I'm crappy in this area of biology but this is why I think so:
Think about cell membranes. When you take something in passively, it's usually non-polar and small such as Oxygen. Many passively taken molecules usually work down a concentration gradient too and don't usally require the cell itself to do anything.
Big or charged molecules usually require energy provided by ATP to enter the membrane.

Now think about a phagocyte taking in something much much bigger, perhaps bacteria. The cell here is taking in the bacteria, the bacteria isn't choosing to enter the phagocyte.
(edited 5 years ago)
Original post by Jack Smith123
It isn't about the size of the molecule but the concentration gradient it is moving against and the type of molecule it is because this will affect what process it will take to move across the cell surface membrane. E.g the pathogen will require atp as there will be low conc. of pathogen inside the phagocyte and high conc of pathogen outside the phagocyte so active transport will have to occur hence mitochondria required to produce atp for endocytosis of the pathogen, right?



Size of molecule does matter, especially in comparison to the phagocyte. If a molecule is too large it cannot pass through the lipid bilayer and use a protein channel (however I'm unsure if this how phagocytes do endocytosis. There are some simple explanations on wikipedia).
Q1 A
Q2 A
Q3 C
Q4 D (I couldn't find anything on kpa but in mmg it is usually around 40?)
Q5 B
Q6 C
Q7 B

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