VCE Biology Question Thread

[Dkontro]

I have gotten "very good" sac marks for the first 3 sacs of the year. I work really hard but I always make mistakes in the sac. Can I still get above 40 for the study score?

[TheAspiringDoc]

I have gotten "very good" sac marks for the first 3 sacs of the year. I work really hard but I always make mistakes in the sac. Can I still get above 40 for the study score?

Certainly you can if you do well on the exam. Also, your school scales up really well so if your doing well on your SACs and exam you could get well above 40

[KingDrogba]

So we did a prac in which we raised the temperature of the room to above 40, and 5 subjects were wrapped in blankets and sleeping bags and we monitored both core and skin temperature. In our results, the skin temperature fluctuated more than the core temperature, can someone explain why?

cheers

[TheAspiringDoc]

So we did a prac in which we raised the temperature of the room to above 40, and 5 subjects were wrapped in blankets and sleeping bags and we monitored both core and skin temperature. In our results, the skin temperature fluctuated more than the core temperature, can someone explain why?

cheers

Hazarding a guess I'd be thinking that the heat was still 'thawing' through (like when you toast some frozen bread and despite the outside being hot when you eat it, the inside is still cold/frozen)?

[tiff_tiff]

hello!

At which stage of cell division are the chromosomes composed of one molecule of DNA?

a. Prophase of mitosis
      
b. Telophase II of meiosis.
      
c. Metaphase II of meiosis.
      
d. The G2 phase of a mitotic cell cycle.

is it b?

i'm under the impression that each chromatid equales 1 dna molecule

[TheAspiringDoc]

hello!

At which stage of cell division are the chromosomes composed of one molecule of DNA?

a. Prophase of mitosis
      
b. Telophase II of meiosis.
      
c. Metaphase II of meiosis.
      
d. The G2 phase of a mitotic cell cycle.

is it b?

i'm under the impression that each chromatid equales 1 dna molecule

I believe it is 'b', as does this: https://au.answers.yahoo.com/question/index?qid=20130413001929AAPJbCp

[sunshine98]

So we did a prac in which we raised the temperature of the room to above 40, and 5 subjects were wrapped in blankets and sleeping bags and we monitored both core and skin temperature. In our results, the skin temperature fluctuated more than the core temperature, can someone explain why?

cheers

This happened because of Homeostasis (the maintenance of a stable internal environment despite changes in the external/internal environment). Temperature is specifically maintained and controlled/regulated due to the fact that enzymes will only function effectively at a specific temperature . Also , you know that if the temp exceeds the critical temp , the enzyme denatures (and obvs enzymes are required for all biochemical/metabolic cellular processes)

[Mieow]

hello!

At which stage of cell division are the chromosomes composed of one molecule of DNA?

a. Prophase of mitosis
      
b. Telophase II of meiosis.
      
c. Metaphase II of meiosis.
      
d. The G2 phase of a mitotic cell cycle.

is it b?

i'm under the impression that each chromatid equales 1 dna molecule

I could almost swear on my LIFE this is a question from ILT 3 for Biomedicine at UoM...

but to answer your question, it is b.

[Rishi97]

hello!

At which stage of cell division are the chromosomes composed of one molecule of DNA?

a. Prophase of mitosis
      
b. Telophase II of meiosis.
      
c. Metaphase II of meiosis.
      
d. The G2 phase of a mitotic cell cycle.

is it b?

i'm under the impression that each chromatid equales 1 dna molecule

Yup it's b and your impression is also correct. Each chromatid is 1 molecule of DNA

[Delirium]

Hi I'm having trouble with this question.


Stress such as exercise can have an effect on the levels of glucose found in blood.
A) assume that a sample of blood was taken immediately before exercising and immediately after exercising. Identify the expected difference in glucose levels between these 2 samples and explain why this difference would occur.

B) Assume that a third blood sample was taken half an hour after exercising. Compare the blood glucose level to that of the sample taken immediately after exercising. Identify the hormone involved and explain its role in altering the level of glucose.

[cosine]

Hi I'm having trouble with this question.


Stress such as exercise can have an effect on the levels of glucose found in blood.
A) assume that a sample of blood was taken immediately before exercising and immediately after exercising. Identify the expected difference in glucose levels between these 2 samples and explain why this difference would occur.

B) Assume that a third blood sample was taken half an hour after exercising. Compare the blood glucose level to that of the sample taken immediately after exercising. Identify the hormone involved and explain its role in altering the level of glucose.

A).
Immediately before exercise: well we will assume that this human was just sitting around before exercising, which means his/her glucose levels should be normal, that is 3.4-7.0mmol glucose in the bloodstream.

Immediately after exercise: because he/she has been exercising, more movements have been occurring and more biological processes are also happening within cells. This means the cells require a larger input of energy as well. So you could say that the glucose from the blood stream will have decreased relatively to the above scenario, as cells require more energy and this is accomplished by glucose being transported into them and is converted into ATP (cellular respiration)

B).
Half an hour after exercising, the majority of glucose in the blood stream has been absorbed by cells and converted into ATP, so the body is still functioning so it still needs energy. So the blood glucose levels decreased, and we know that when this happens, stored glycogen is broken down into glucose by a molecule called glucagon (the hormone that is responsible for the stimulation of this process).

Hope it helped!

[mahler004]

Immediately after exercise: because he/she has been exercising, more movements have been occurring and more biological processes are also happening within cells. This means the cells require a larger input of energy as well. So you could say that the glucose from the blood stream will have decreased relatively to the above scenario, as cells require more energy and this is accomplished by glucose diffusing into them and is converted into ATP (cellular respiration)

Glucose doesn't enter cells via diffusion - it enters through a series of active or passive (facilitated diffusion) protein transporters.

[Rishi97]

Hi I'm having trouble with this question.


Stress such as exercise can have an effect on the levels of glucose found in blood.
A) assume that a sample of blood was taken immediately before exercising and immediately after exercising. Identify the expected difference in glucose levels between these 2 samples and explain why this difference would occur.

B) Assume that a third blood sample was taken half an hour after exercising. Compare the blood glucose level to that of the sample taken immediately after exercising. Identify the hormone involved and explain its role in altering the level of glucose.

Have you learnt about insulin and glucagon yet?

[cosine]

Glucose doesn't enter cells via diffusion - it enters through a series of active or passive (facilitated diffusion) protein transporters.

My bad, amended.

[Delirium]

A).
Immediately before exercise: well we will assume that this human was just sitting around before exercising, which means his/her glucose levels should be normal, that is 3.4-7.0mmol glucose in the bloodstream.

Immediately after exercise: because he/she has been exercising, more movements have been occurring and more biological processes are also happening within cells. This means the cells require a larger input of energy as well. So you could say that the glucose from the blood stream will have decreased relatively to the above scenario, as cells require more energy and this is accomplished by glucose being transported into them and is converted into ATP (cellular respiration)

B).
Half an hour after exercising, the majority of glucose in the blood stream has been absorbed by cells and converted into ATP, so the body is still functioning so it still needs energy. So the blood glucose levels decreased, and we know that when this happens, stored glycogen is broken down into glucose by a molecule called glucagon (the hormone that is responsible for the stimulation of this process).

Hope it helped!

Thanks so much