Section 1, Part A - Multiple Choice (4 Viewers)

[hsc2012la]

Haemoglobin provides an adaptive advantage to an endotherm in a cold environment because it allows. A) more oxygen to be dissolved in plasma. b) the organism to decrease its metabolic rate. c) more energy to be available to the organism. d) less carbon dioxide to be transported in the blood. what did you guys put?

c

 

[TheOptimist]

Could 6 be D though?
Because C is increase antibodies against disease but shouldn't vaccines increase memory B and T cells
And D was decrease number of antigens that trigger an immune response because after vaccines, it takes less antigens to trigger the immune response and start the secondary response??

D)They decrease the number of antigens taht trigger the immune response,
imo this is incorrect your deduction does not link to D
rather the immune response will release more antibodies on re-exposure, it does not mean that it will take less antigens to trigger the immune response

 

[RUBYTUESAY]

Antidiuretic hormone (ADH or vasopressin) controls water reabsorption in the nephron. When levels of fluid in the blood drop, the hypothalamus causes the pituitary to release ADH. This increases the permeability of the collecting ducts to water, allowing more water to be absorbed from the urine into the blood. The resulting urine is more concentrated. When there is too much fluid in the blood, sensors in the heart cause the hypothalamus to reduce the production of ADH in the pituitary, decreasing the amount of water reabsorbed in the kidney. This results in a lower blood volume and larger quantities of more dilute urine.

Can this answer question 15?
Looking at this I would put down B
Also, what did everyone put for q6?

 

[Newbit]

Could 6 be D though?
Because C is increase antibodies against disease but shouldn't vaccines increase memory B and T cells
And D was decrease number of antigens that trigger an immune response because after vaccines, it takes less antigens to trigger the immune response and start the secondary response??

Q6. How do vaccinations prevent disease?
They prevent the disease by exposing the body to a weakened strain of the disease which creates antibodies, therefore increasing the number of antibodies against that pathogen.

 

[TheOptimist]

Thoughts on Q12?

What was there to be thought about?

 

[Chulbul Pandey]

Re: General Thoughts: Biology

You're not crazy, DNA polymerase is the enzyme in DNA replication

Catalase is the enzyme in liver (and potatoes)
as for me... I wrote catalase and confused myself later on, crossed it out and wrote amylase

Woopss..I think I meant peroxidase...there goes another mark!

 

[SandyS1995]

Thoughts on Q12?

Got it wrong because i had no idea what it was. we never went through that in class

 

[kentonite]

The biscuit one is easy.. the question is asking whats the difference between natural selection and the experiment about biscuits. the answer is that the biscuits can't reproduce..

 

[desmol]

The biscuit one is easy.. the question is asking whats the difference between natural selection and the experiment about biscuits. the answer is that the biscuits can't reproduce..

agreed, the only other viable option was an observation, not a limitation of the experiment

 

[Kimyia]

D)They decrease the number of antigens taht trigger the immune response,
imo this is incorrect your deduction does not link to D
rather the immune response will release more antibodies on re-exposure, it does not mean that it will take less antigens to trigger the immune response

Ok, I'm confused because the Bio in Focus textbook says:
"The secondary response:
- is more rapid and requires less antigen to initiate it"

 

[desmol]

Got it wrong because i had no idea what it was. we never went through that in class

All it was asking was where is there more nitrogenous wastes - the collecting tubule contains the most because products of the kidney and osmoregulation all end up there

 

[kentonite]

Thoughts on Q12?

I wrote that as D because i thought collecting ducts were only permeable to water and salts by hormones ADH and aldoesterone

 

[andrewandrewc]

Aw man 18. Forgot xylem was dead LOL!

 

[desmol]

Ok, I'm confused because the Bio in Focus textbook says:
"The secondary response:
- is more rapid and requires less antigen to initiate it"

But immunity is the 3rd line of defense, not the 2nd

 

[Kimyia]

But immunity is the 3rd line of defense, not the 2nd

Secondary response means the re-exposure to a pathogen after being first exposed with a vaccine.

 

[wavess]

What about question 11? What was the answer?

 

[desmol]

Secondary response means the re-exposure to a pathogen after being first exposed with a vaccine.

Oops, sorry hehe

 

[Kimyia]

Oops, sorry hehe

haha all good

 

[TheOptimist]

But immunity is the 3rd line of defense, not the 2nd

she's reffering to the re-exposure of the antigen in the body "the secondary response" not 2ndline/3rd line,

 

[Chulbul Pandey]

YEAHHH!! What was the answer to the hybrid question?? I wrote the apples..