Biology Paper 1

[altox876]

It dosent matter...if air temperature is higher, thermoreceptors will detect this and transmit impulses to hypothalamus and set the negative feedback process into action...Confirmed..by the following source
BBC Bitesize.(England's Revision Source for GCSE exams)

The question was not about whether vasodilation occurs in that situation. Rather it asked whether it would contribute to heat loss by body, which in this case I think its contribution would be negligible because of the temperature difference between the skin and the air.

 

[altox876]

how can core be higher than suface temp in hot surroundings

Ok, this I may be wrong about but read my other post.

 

[danial 234]

altox how do u know the temp of air or body in that situation. you cant make assumptions

 

[altox876]

altox how do u know the temp of air or body in that situation. you cant make assumptions

I have made no assumptions. The question said that air temp is higher than body temperature.

 

[danial 234]

I have made no assumptions. The question said that air temp is higher than body temperature.

exactly, i m saying that how do u know that the difference between them is larger or smaller

 

[altox876]

exactly, i m saying that how do u know that the difference between them is larger or smaller

Since the question explicitly mentioned a difference, in my opinion, it was supposed to be taken into account. If the surrounding temperature is higher, heat will not flow from skin to the air(the mode of action of vasodilation). Sweating would occur, which would take latent heat. This is my logic and I accept that I am probably wrong.

 

[thementor]

exactly, i m saying that how do u know that the difference between them is larger or smaller

Since the question explicitly mentioned a difference, in my opinion, it was supposed to be taken into account. If the surrounding temperature is higher, heat will not flow from skin to the air(the mode of action of vasodilation). Sweating would occur, which would take latent heat. This is my logic and I accept that I am probably wrong.

look guyz it said air temp is higher than core body temp. and so it means that thermoreceptors will detect this differnce in temperature and so sweating and vasodialtion will occur but not shivering the asnwer was cross tick tick. Period and end of story.

 

[Haris Sal11]

1) what is present in root hair cell? nuclues present, cholorphyll avsent
2) what was of chlorine and nitrates ? chloride diffusion, nitrates active transport
3) what was the color od starch test? bl bl bl yellow
4) which leaf is experimented for presence of chlorophyll ? variegated one
5) where does evapouration occurs in a plant( was it guard cell or mesophyll spongy) the diagram ? stomate (guard cells)
6) what was the orange test ? glucose
7) what was the organ and blood going and comming ? lungs
8) where was glucose present most ? hepatic portal vein
9) was it FSH, LH, oestrogen, progestosterone ? oestrogen *confirmed*
10) what was the alelles answer ? B (two alleles for height gene)
11) what was artifical selection ? B mating bulls
12) what was meiosis diagram answer ? C last one division
13) what was the mosquito answer ? Water one
14) effect of global warming ? reduction
15) what was the ball and socket answer ? 3 and 5 (D)
16) what was the answer of the graph of diapraghm ? (A, before rise of volume)
17) Cross Pollination, a flower on one plant pollinates a flower on other plant of same species
18) where substance exchange occur between mother and baby? uterus wall
19) what was the cerebrum, cerebellum, medulla oblongata, hypothalamus ? B or A one
20) what was the Q P R answer of eye focusing ? Q P
21) what was P Q R S in which bacteria were involved ? Q AND R
22) what was the answer to artries compared with veins ? more elastic tissues
23) where respiration and photosythesis occured at X and Y ? tick tick cross tick
24) what was answer of DNA and made up of cells answer ? bacteria - virus
25) what was the answer of cuticle( plz confirm was it non cellular or made of cells which allowed light to pass and prevented water)? cuticle is non cellular, it is a result of cellular activity but is not made of cells and main purpose of it being to prevent transpiration or water loss
26) what was the organism that feeds on producer and consumer? A) 2
27) which was producer in block diagram ? B small box
28) what was the secretion answer of insulin ? varied varied
29) what was the answer of transport of water in leaf, root and stem ? C 1,4,6 something
30) what was the answer of venn diagram of evaporation muscle contraction and diffusion ? B diffusion an muscle action
31) scientist one - 2 fruits
32) down's syndrome - D) 47 -zygote
33) funtion of p through liver from ileum; transport glucose to liver
34)Global warming - sea level reduction
35)anaerobic respiration comparsion - CO2 produced/not produced one
36) pH acidic made by lactose breakdown
37)Example of active transport- movement of glucose through villi
38) purple yellow CO2 concentration
39) Lungs - A one before volume starts increasing
40) how body loses heat? skeletal activity no, others two sweat and vasodilataion yes

Aerobic respiration, CO2 option is wrong. It was glucose. In yeast, Glucose is not used, in humans it is. Lactose is used in yeast.

 

[Talha Irfan]

Aerobic respiration, CO2 option is wrong. It was glucose. In yeast, Glucose is not used, in humans it is. Lactose is used in yeast.

Bro, one thing, it was Anaerobic* and in humans anaerobic respiration never produces Co2 but only lactic acid and energy refer to pg-165 of biology 'a course for o-level' and in yeast glucose is used ; remember alcoholic fermentation

 

[redd]

sis, LH was given see ur quoted url and try remembering the graph, on 14th day, the graph which went to max was LH and the small hump was FSH which was exactly below as it is , only Oestrogen was not shown. The pressure one was A before volume begins to rise

well, still m confused, there was no such curve that was rising between 1-7 days and FSH secretion is stimulated after the breakdown of uterine lining in 1-7 day. i can remember oestrogen curve there. FSH was msiing, there was no curve for it.

 

[danial 234]

well, still m confused, there was no such curve that was rising between 1-7 days and FSH secretion is stimulated after the breakdown of uterine lining in 1-7 day. i can remember oestrogen curve there. FSH was msiing, there was no curve for it.

FSH was there. remember there was a very small curve at 14

 

[Talha Irfan]

well, still m confused, there was no such curve that was rising between 1-7 days and FSH secretion is stimulated after the breakdown of uterine lining in 1-7 day. i can remember oestrogen curve there. FSH was msiing, there was no curve for it.

*See The Chart, The Red One Is For Oestrogen -------------->

 

[thementor]

Aerobic respiration, CO2 option is wrong. It was glucose. In yeast, Glucose is not used, in humans it is. Lactose is used in yeast.

dude glucose is used in yeast

 

[thementor]

Bro, one thing, it was Anaerobic* and in humans anaerobic respiration never produces Co2 but only lactic acid and energy refer to pg-165 of biology 'a course for o-level' and in yeast glucose is used ; remember alcoholic fermentation

exactly glucose is used in both

 

[redd]

*See The Chart, The Red One Is For Oestrogen --------------> View attachment 28240

well, as per i remember and as per my knowledge, i still think FSH was missing, well cant say anything, i may be wrong.

 

[Talha Irfan]

well, as per i remember and as per my knowledge, i still think FSH was missing, well cant say anything, i may be wrong.

oh good lord ; u r still in doubt

 

[redd]

oh good lord ; u r still in doubt

well, just a question of 1 mcq, we need A*s, and inshaa Allah will get them.

 

[UFO_far_planet]

http://coachsci.sdsu.edu/csa/vol36/rushall1.htm
During exercise the body produces a great deal of heat. In extreme circumstances this can elevate its core temperature from 37° C to beyond 40° C. When the surrounding air is cool heat can be lost from the body by the process of radiation (transfer of heat by electromagnetic waves), convection (by air movement), conduction (by contact), and evaporation (by sweating). As the surrounding temperature increases it becomes more and more difficult to lose heat by radiation, convection, and conduction. Hence, the predominant source of heat loss in warm to hot conditions is from the evaporation of sweat on the skin surface.

According to this the answer of question 20 homeostasis should have been D. What are everyone's thoughts?

You're right. I chose D.

 

[UFO_far_planet]

look guyz it said air temp is higher than core body temp. and so it means that thermoreceptors will detect this differnce in temperature and so sweating and vasodialtion will occur but not shivering the asnwer was cross tick tick. Period and end of story.

thementor, calm down, and then refer to pg 203 paragraph 2 of 'federal biology: a course for o'level' by lam peng kwan, if u have it.
I could be wrong, but do have a look.