VCE Biology Question Thread

[GodNifty]

Thank you for that! Yeah, sorry I meant to action not active. Sorry, I have another question about neurons. Are they electrical impulses or chemical signals? I'm sorry, I cannot get the hang of them

This is the part where I let someone else more knowledgeable than me to answer you, but an action potential is an electrical impulse.

An action potential actually happens from the entry (and exit) of sodium ions into the axon cytoplasm and exit (and entry) of potassium ion outside the axon. These ions are electrically charged

You don't need to know this at all for biology so don't worry about it.

Hey everyone! I was just wondering whether anyone knew whether or not we were required to memorize the different hormones for animals and plants? For example, glucocorticoids and mineralocorticoids are in the adrenal cortex and then the hormone class or each, target, function, etc. Same goes with plants? Thanks in advance everyone!

Don't think so, but maybe know the basic ones for plants like ethylene. Pheromones should be fine for animals (sorry, can't remember the study design at all lol)

[Chocolatemilkshake]

Sorry, I have another question about neurons. Are they electrical impulses or chemical signals? I'm sorry, I cannot get the hang of them

The action potential which travels across the neuron is an electrical signal. This electrical signal is converted into neurotransmitters at the axon (end of the neuron). These neurotransmitters are chemical signals and they transmit the signal across the synaptic cleft from the axon of one neuron to the dendrites of the next. For biology units 3/4 you just need to generally know that this is the role of neurotransmitters.

Hey everyone! I was just wondering whether anyone knew whether or not we were required to memorize the different hormones for animals and plants? For example, glucocorticoids and mineralocorticoids are in the adrenal cortex and then the hormone class or each, target, function, etc. Same goes with plants? Thanks in advance everyone!

Nope definitely not that detailed. If you know how a few of the basic hormones work though, that could help with understanding the content.

[Moonblossom]

Hey, sorry, another question. What is the difference between neurotransmitters and neurohormones? Thanks in advance!

[Chocolatemilkshake]

Hey, sorry, another question. What is the difference between neurotransmitters and neurohormones? Thanks in advance!

Neuotransmitters are chemical signalling molecules that carry a message directly across a synapse (travel directly between two neurons or a neuron and target cell). Neurohormones are similar and are also released by a neuron, however, they are released into the blood stream and travel a short distance in the blood before reaching its target (hence neurohormone as it uses the blood stream like a hormone does). However, generally neurohormones travel in small specialised capillaries and don't travel such long distances (and throughout the entire blood stream) like hormones.

Just note, knowledge of neurohormones isn't really necessary for the VCE course, although I guess it's useful to know the difference 

[chiarra]

Hi, I'm going back through my notes and I have a question about the light-dependent and light-independent inputs and outputs of each? I look at other notes but everyone has a different answer so I don't know what the exact input and outputs of each stage are?

[Moonblossom]

Hi, I'm going back through my notes and I have a question about the light-dependent and light-independent inputs and outputs of each? I look at other notes but everyone has a different answer so I don't know what the exact input and outputs of each stage are?

In my school for the light dependent stage we had the inputs as light energy, water, NADP+, ADP and Pi. For outputs we had NADPH, ATP and oxygen gas (waste product).

For the light independent stage the inputs were NADPH, ATP and carbon dioxide and the outputs were a molecule of glucose, NADP+, ADP and Pi.

Don't know how much this helps

[makram]

In terms of the dot point: 'the use of monoclonal antibodies in treating cancer'-- what exactly is required for us to know?

[Chocolatemilkshake]

In terms of the dot point: 'the use of monoclonal antibodies in treating cancer'-- what exactly is required for us to know?

I personally learnt what a monoclonal antibody was and a few different ways that they are utilised to treat cancer (it's actually really interesting!). At our school we also had to know how a monoclonal antibody was produced although I believe that this is a bit beyond the study design.

[J_Rho]

In terms of the dot point: 'the use of monoclonal antibodies in treating cancer'-- what exactly is required for us to know?

Adding onto what CM said, these are my monoclonal antibody notes from last year

Here are some VCE resources on monoclonal antibodies you may find helpful
BioNinja - Acquired Immunity
Contemporary VCE Bio - Monoclonal Antibodies and Cancer Treatment
Free VCE Notes - Immunity

[justinely]

Are the terms "MHC class I PROTEINS" and "MHC class I MARKERS" interchangeable? Do "proteins" and "markers" refer to the same thing? When do u use which?

The innate 2nd line of defence consists of Cellular Response and Humoral Response........ which one happens first?
Or do they happen at the same time?

Mod Edit: Merged Double Post

[J_Rho]

Are the terms "MHC class I PROTEINS" and "MHC class I MARKERS" interchangeable? Do "proteins" and "markers" refer to the same thing? When do u use which?

In my experience I've never heard them being called proteins (only markers), and the study design and examiners reports don't offer much nor tell us what we should call them. I personally would stick with MHC 1 Markers (but as long as you say MHC 1 it should be fine...and i mean they ARE proteins suppose it might depend on the context?), as that's what they seem to be most commonly called. Perhaps another user (or your teacher) may be able to shed more light on this

The innate 2nd line of defence consists of Cellular Response and Humoral Response........ which one happens first?
Or do they happen at the same time?

The difference is that humoral happens when it's in the extracellular fluid and cellular is in the cells so they are separate processes as one involved B cells and the other involves Cytotoxic T cells so I do believe they can happen at the same time it just depends where the infection is (i imagine most of the time it would either be just in extracellular fluid AND cells OR just extracellular fluid), not certain tho so don't take this as fact.

My notes from last year

Edit: typo

[linesido]

In my experience I've never heard them being called proteins (only markers), and the study design and examiners reports don't offer much. I personally would stick with MHC 1 Markers, as that's what they seem to be most commonly called. Perhaps another user (or your teacher) may be able to shed more light on this

When im answering questions, I call them proteins or somethings molecule. I dont think it really matters.

[justinely]

In my experience I've never heard them being called proteins (only markers), and the study design and examiners reports don't offer much. I personally would stick with MHC 1 Markers, as that's what they seem to be most commonly called. Perhaps another user (or your teacher) may be able to shed more light on this
The difference is that humoral happens when it's in the extracellular fluid and cellular is in the cells so they are separate processes as one involved B cells and the other involves Cytotoxic T cells so I do believe they can happen at the same time it just depends where the infection is (i imagine most of the time it would either be just in extracellular fluid AND cells OR just extracellular fluid), not certain tho so don't take this as fact.

My notes from last year

Edit: typo

Ohhh. I have the Heinemann textbook and they call it MHC proteins, but I some other sources call it markers. That's why I was confused. Thanks for your input though!

[GodNifty]

In my experience I've never heard them being called proteins (only markers), and the study design and examiners reports don't offer much. I personally would stick with MHC 1 Markers, as that's what they seem to be most commonly called. Perhaps another user (or your teacher) may be able to shed more light on this
The difference is that humoral happens when it's in the extracellular fluid and cellular is in the cells so they are separate processes as one involved B cells and the other involves Cytotoxic T cells so I do believe they can happen at the same time it just depends where the infection is (i imagine most of the time it would either be just in extracellular fluid AND cells OR just extracellular fluid), not certain tho so don't take this as fact.

My notes from last year

Edit: typo

The innate 2nd line of defence consists of Cellular Response and Humoral Response........ which one happens first?
Or do they happen at the same time?

Humoral response is a third line of defence, not 2nd. By 'cellular response', do you mean 'cell-mediated response'? That's also a third line of defence. J_Rho is right in saying that it depends on the infection, typically on whether it's bacterial (typically humoral, but could be a intracellular parasite) or viral (cell-mediated).

MHC1 proteins and markers are the same thing, but I'd probably stick with markers instead.

[justinely]

Humoral response is a third line of defence, not 2nd. By 'cellular response', do you mean 'cell-mediated response'? That's also a third line of defence. J_Rho is right in saying that it depends on the infection, typically on whether it's bacterial (typically humoral, but could be a intracellular parasite) or viral (cell-mediated).

MHC1 proteins and markers are the same thing, but I'd probably stick with markers instead.

By 'cellular response', I mean phagocytes and antigen presenting cells, so the 2nd line of defence. And by "humoral response", I mean complement proteins, cytokines, inflammation and fever, so in the 2nd line of defence also. There are cellular and humoral responses in the 3rd line of defence too, but they're different. And thanks for the clarification about the MHCs markers!!


The cellular response of the innate immune system can consist of phagocytes and antigen presenting cells. phagocytes can quickly eliminate PATHOGENS by engulfing them and breaking them down with digestive enzymes, and then releasing them out. but in another process,  phagocytosis of an ANTIGEN occurs, except it is followed by an class II MHC protein binding onto one of the fragments of the antigen and presenting it to a helper T cell......... how come the phagocytosis of a pathogen (first process i mentioned), doesn't involve MHC proteins? or similarly, why can't the second process not involve MHC proteins?

Mod Edit: Merged Double Posts