VCE Biology Question Thread

[Billuminati]

If someone could help with this question
Using the law of Laplace explain how surfactants stabilise alveoli of different sizes that share the same alveolar duct

It wasn't covered in the 2nd year physiology unit in Monash biomed, but from a quick look at my uni textbook I think you need to explain it in terms of "as radius increases, pressure decreases"

[Chocolatepistachio]

if someone could help with this question

[Chocolatepistachio]

Enkephalins and endorphins are peptide neurotransmitters that function in the perception of pain. This is because
A they interact with specific opioid receptor proteins to produce their effects
B they are small enough to directly enter post synaptic membranes
C they have special membrane channels that let them through the post-synaptic cells
D. They interact with morphine

Would this be a

[Billuminati]

Enkephalins and endorphins are peptide neurotransmitters that function in the perception of pain. This is because
A they interact with specific opioid receptor proteins to produce their effects
B they are small enough to directly enter post synaptic membranes
C they have special membrane channels that let them through the post-synaptic cells
D. They interact with morphine

Would this be a

Yes pretty much every neurotransmitter produce an effect by binding to a receptor, similar to hormones

[-Lilac-]

if someone could help with this question

Is there any more context to this question, maybe from what you have been focusing on in class? There are a few things you could mention here. An obvious one would be whether the cytokine is acting in a paracrine vs autocrine manner. Or you could talk about whether is Is it having an inhibitory or stimulating effect on something.

[greenpaper]

Why are adult stem cells not more likely to be rejected by the patient's body than embryonic stem cells.

[greenpaper]

Why are embryonic stem cells easier to isolate and grow in the lab than Adult stem cells

[Billuminati]

Why are adult stem cells not more likely to be rejected by the patient's body than embryonic stem cells.

It's because they have specialised and have developed distinct markers that identify them as non self to the host immune system. Embryonic stem cells don't have this specialisation, they can be easily integrated in a transplant. In fact, due to their tendencies to grow and proliferate, embryonic stem cell transplants are plagued by the problem of too much growth to the degree that it will cause a malignant tumour

Adult stem cells are found scattered in different places that may be hard to reach eg bone marrow whereas you can just grow a ball of embryonic stem cells if ethical guidlines permit it.

[Chocolatepistachio]

If someone could help with this question
Which of the following chemical messengers is able to cross the phopholipid bilayer of the cell membrane?
A amino acids
B amines (excluding thyroid hormone)
C peptides
D eicosanoids

[Billuminati]

If someone could help with this question
Which of the following chemical messengers is able to cross the phopholipid bilayer of the cell membrane?
A amino acids
B amines (excluding thyroid hormone)
C peptides
D eicosanoids

It's D because eicosanoids are fatty acid derivatives and are therefore hydrophobic

[biology1234]

During which stage of mitosis do the centromeres split?
Would this be during anaphase, as I know that spindle fibres pull sister chromatids to opposite ends of cell.

[biology1234]

what is difference between cytokinesis in animal cells and cytokinesis in plate cells.

[tiredandstressed]

what is difference between cytokinesis in animal cells and cytokinesis in plate cells.

To answer your questions let's review what is cytokinesis
Cytokinesis: is the division of cytoplasm
Cytosol and organelles in the cytosol are distributed around the new nuclei
These all then become enclosed within a new plasma membrane

Plants require the development of a cell plate due to the presence of the cell wall , however, animal cells do not have this process due to the absence of a cell wall

[greenpaper]

The study design discusses the following dot point- the key events in meiosis that result in the production of gametes from somatic cells.
What does it mean by from somatic cells?

[Chocolatepistachio]

Any cell in the body except sex cells