Maintaining a balance marathon! (1 Viewer)

[Aysce]

Alright guys, we're only sticking with one topic at a time ie. One thread for MAB, another for BOL and vice versa. So basically, each person will post a question after they have answered a question from the previous post. These questions SHOULD be taken from past papers or trial papers, but some from other sources will suffice as well.

Le start with something simple.

Q. Plants, like many other living things, need adaptations to assist in minimising their water loss. Describe TWO adaptations shown by terrestrial AUSTRALIAN plants that assist them in minimising water loss. (3 marks)

Note: Notes can be used to aid you but it is better if you try to answer the question yourself.

When posting responses, I encourage people to say how a person can improve their answers so that they can extend themselves and make their answers more concise yet detailed.

 

[Dylanamali]

wooo bio time =P

 

[Aysce]

wooo bio time =P

Wasn't smart to post it at this time ahah

 

[Parvee]

eww a bio marathon

 

[Kimyia]

Q. Plants, like many other living things, need adaptations to assist in minimising their water loss. Describe TWO adaptations shown by terrestrial AUSTRALIAN plants that assist them in minimising water loss. (3 marks).

Some Australian terrestrial plants, like Eucalypts, have adapted vertically hanging leaves to assist in minimising water loss. Vertically hanging leaves present less surface area to the sun during high radiation at midday and so less stomates are exposed to the heat and thus less water is evaporated. Another adaptation shown in some Australian terrestrial plants, such as that in the Atriplex salt bushes, is to change the reflectiveness of their leaves during leaf development so that they have highly reflective leaves during summer. This means a greater amount of heat can be reflected away from the leaf and so there is less heat to evaporate water from the plant, thus minimising water loss.

Next question!
Describe ONE theory about the processes responsible for the movement of materials through phloem tissue (3 marks)

 

[Dylanamali]

^ great answer.

 

[Aysce]

A theory explaining the processes catalysing the movement of materials through the phloem tissue is the Source-Path-Sink theory. The source-path-sink theory suggests that the products of photosynthesis such as glucose, undergo active transport into one end of the phloem known as the source where organic materials are produced. These materials will then travel to the other end of the phloem, called the sink which is the site of need, where they will be actively unloaded into the surrounding tissues. As a result of the differences in osmotic pressure between the water and sugar concentrations, water will flow in when the phloem is being loaded at the source, while water will flow out when the materials are being unloaded at the sink.

I did these with notes beside me because I honestly suck at plant work. Is there anyway I can improve my answer?

Nek question.

Question 34.

Draw a labelled diagram to show how a specific feedback mechanism plays an essential role in homeostasis.

 

[Aysce]

Cmon guys..

 

[Boonyak]

Not my diagram but meh.

 

[Boonyak]

Not my diagram but meh.
View attachment 24434

Why is the maintenance of a constant internal environment important for metabolic efficiency? ( easy 1 )

 

[SunnyScience]

Not my diagram but meh.
View attachment 24434

Why is the maintenance of a constant internal environment important for metabolic efficiency? ( easy 1 )

A constant internal environment is needed so that enzymes will always be working at an optimum rate, and thus metabolism will be at optimum efficiency.


Distinguish between active and passive transport and relate these to processes occurring in the mammalian kidney.

 

[Kimyia]

A constant internal environment is needed so that enzymes will always be working at an optimum rate, and thus metabolism will be at optimum efficiency.


Distinguish between active and passive transport and relate these to processes occurring in the mammalian kidney.

Active transport requires energy to move substances against a concentration gradient. This can be seen in the kidney where energy is required to reabsorb glucose and amino acids so they are not lost in urine and a sodium pump mechanism actively transports sodium ions from urine back into the kidney cells to conserve salt when necessary.
Passive transport requires no energy as substances are moved along a concentration gradient (includes diffusion and osmosis). This can be seen in the kidney as water is reabsorbed throughout the nephron passively by osmosis and urea diffuses into the nephron down a concentration gradient.

New question: (easy one) Describe ONE adaptive advantage of haemoglobin - 2 marks.

 

[Aysce]

Active transport requires energy to move substances against a concentration gradient. This can be seen in the kidney where energy is required to reabsorb glucose and amino acids so they are not lost in urine and a sodium pump mechanism actively transports sodium ions from urine back into the kidney cells to conserve salt when necessary.
Passive transport requires no energy as substances are moved along a concentration gradient (includes diffusion and osmosis). This can be seen in the kidney as water is reabsorbed throughout the nephron passively by osmosis and urea diffuses into the nephron down a concentration gradient.

New question: (easy one) Describe ONE adaptive advantage of haemoglobin - 2 marks.

One adaptive advantage of haemoglobin is the ability of it in being able to have a higher affinity to oxygen molecules with each subsequent one being attached. When an oxygen molecule is attached to haemoglobin, the ability of the haemoglobin in being able to attach to another oxygen molecule increases until all four slots have been filled by oxygen. As a result of this, haemoglobin will have a higher likelihood of carrying the maximum load of oxygen molecules, hence enabling more oxygen to be delivered to their site of need and improving the efficiency of the functioning of the haemoglobin.

NEK QUESTION.

Question 26.
a. Name TWO products extracted from donated blood and state their uses. (4 marks)
b. Propose ONE reason why scientists have now begun to develop artificial blood. (1 mark)

 

[jnney]

a. Name TWO products extracted from donated blood and state their uses. (4 marks)
b. Propose ONE reason why scientists have now begun to develop artificial blood. (1 mark)

a) platelets: given to patients who have undergone chemotherapy. the treatment kills both cancer cells and good cells. hence receivers are provided with platelets to prevent dangerous and spontaneous bleeding.

red blood cells: given to anemic patients as they are deficient in rbc - rbc contain haemoglobin which delivers oxygen to all parts of body essential for survival.

b) donated blood contains diseases which is time consuming and costly to test which is a disadvantage. on the other hand, artificial blood will already be sterilised and used immediately.

 

[jnney]

how do we know if we're providing enough / the relevant points for each question? :/


Some people cannot secrete aldosterone. Outline how this condition may be treated. (1 mark).

 

[RandoM_TerroR]

oi, guys when are your half yearlies comin?

 

[jnney]

oi, guys when are your half yearlies comin?

week 9-10

 

[jnney]

A constant internal environment is needed so that enzymes will always be working at an optimum rate, and thus metabolism will be at optimum efficiency.

State that enzymes can only work in a limited range of conditions (pH, temp etc). Enzymes are also biological catalysts that control the reactions of cells necessary for survival.] in organisms.

One adaptive advantage of haemoglobin is the ability of it in being able to have a higher affinity to oxygen molecules with each subsequent one being attached. When an oxygen molecule is attached to haemoglobin, the ability of the haemoglobin in being able to attach to another oxygen molecule increases until all four slots have been filled by oxygen. As a result of this, haemoglobin will have a higher likelihood of carrying the maximum load of oxygen molecules, hence enabling more oxygen to be delivered to their site of need and improving the efficiency of the functioning of the haemoglobin.
?

I think you should explain why it is so important that haemoglobin has a high oxygen carrying capacity. mammalians require a continual supply of oxygen for aerobic respiration so energy can be generated for movement, growth etc. hence haemoglobin has an adaptive advantage of mammals as it is able to deliver large amounts of oxygen to the cells.

 

[Aysce]

State that enzymes can only work in a limited range of conditions (pH, temp etc). Enzymes are also biological catalysts that control the reactions of cells necessary for survival.] in organisms.



I think you should explain why it is so important that haemoglobin has a high oxygen carrying capacity. mammalians require a continual supply of oxygen for aerobic respiration so energy can be generated for movement, growth etc. hence haemoglobin has an adaptive advantage of mammals as it is able to deliver large amounts of oxygen to the cells.

True..truee..

 

[Alkanes]

I will be using this thread to study for my half yearlies. So post some more questions + quality answers haha