Biology paper 3

[whitetiger64]

can u tell me what does pH have to do with photosynthesis or anything else, what is pH in general, thx

pH is the measurement of the acidity or alkalinity of a substance. pH plays an important role in the activity of enzymes. So at an optimum pH level, the enzymes will work faster. Therefore the general referance to pH in any chemical reaction will mostly be because it is an enzyme-controlled reaction.

 

[whitetiger64]

The sylabus says "Describe the process of chewing".

How???

CHEWING:
The chewing muscles contract and relax to move the lower jaw up and down, this makes the food between teeth to be cut and crushed. The tongue helps by moving food between teeth.

 

[Mahdi]

can u tell me what does pH have to do with photosynthesis or anything else, what is pH in general, thx

The pH is short for (Potential Hydrogen), It is simply a scale to measure acidity or alkalinity of the soil.
Now how does that effect the rate of photosynthesis?
Well, the enzymes present in the plants need an optimum pH to work. If the soil is too acidic or too alkaline enzymes are denatured, bringing a halt on the reactions in plant cells.
Plants usually need a neutral pH as they contain water mostly.

Hope that helps.

 

[Mahdi]

Guys can anybody explain osmoregulation and with examples plz it would be a lot of help to me !!

To maintain balance between water and dissolved materials in an organism.
Like we humans (vertebrates) have an osmoregulatory organ, kidneys to excrete excess water, nitrogen, salts etc.

That's all I understand from it..sorry if insufficient.

 

[dana xP]

To maintain balance between water and dissolved materials in an organism.
Like we humans (vertebrates) have an osmoregulatory organ, kidneys to excrete excess water, nitrogen, salts etc.

That's all I understand from it..sorry if insufficient.

its quiet just wht i wanted thanx

 

[Fatima_Toomii]

Guys can anybody explain osmoregulation and with examples plz it would be a lot of help to me !!

Osmoregulation occurs in the collecting ducts found in the nephrons which are located in the kidneys. It's basically the balancing of the amount of water found in your body. The hypothalamus is a part of the brain which also monitors the water potential of the blood (if there is too much water or too little water), and in the case of a dehydrated person, for example, it will stimulate the pituitary gland to release ADH (antidiuretic hormone). ADH will increase the level of water absorbed, so there is enough water in the dehydrated person's body.

So, simply put, osmoregulation causes more water to be absorbed if your body is dehydrated or more water to be excreted if your body has sufficient amounts of water in it.

Hope that helped

 

[dana xP]

Osmoregulation occurs in the collecting ducts found in the nephrons which are located in the kidneys. It's basically the balancing of the amount of water found in your body. The hypothalamus is a part of the brain which also monitors the water potential of the blood (if there is too much water or too little water), and in the case of a dehydrated person, for example, it will stimulate the pituitary gland to release ADH (antidiuretic hormone). ADH will increase the level of water absorbed, so there is enough water in the dehydrated person's body.

So, simply put, osmoregulation causes more water to be absorbed if your body is dehydrated or more water to be excreted if your body has sufficient amounts of water in it.

Hope that helped

ya thanx alot

 

[Fatima_Toomii]

ya thanx alot

You're welcome

 

[Mahdi]

its quiet just wht i wanted thanx

Anytime
All the best!

 

[Lost_Life]

can u tell me what does pH have to do with photosynthesis or anything else, what is pH in general, thx

pH Is the alkalinity or acidity of something, ph can affect photosynthesis ( enzymes present in plants )

 

[Lost_Life]

GUYS
MAY SOMEONE STATE THE ADS AND DISADS OF SEXUAL AND ASEXUAL REPRO
AND ALSO THE ADS AND DISADS OF USING FERTILIZERS
THANKS

 

[Fatima_Toomii]

GUYS
MAY SOMEONE STATE THE ADS AND DISADS OF SEXUAL AND ASEXUAL REPRO
AND ALSO THE ADS AND DISADS OF USING FERTILIZERS
THANKS

Do you mean natural or chemical fertilisers?

 

[dana xP]

advantages of asexuall reproduction
-less time consuming
-only one parent is needed

disadvantages of asexuall reproduction
-no variation in offspring
-increase competitions between offspring

advantages of sexual reproduction
-leads to variation
-offsprings r more adapted to the environment

disadvantages of sexual reproduction
-takes a longer time than asexual
-2 parents r needed

 

[Lost_Life]

Do you mean natural or chemical fertilisers?

both

 

[Fatima_Toomii]

GUYS
MAY SOMEONE STATE THE ADS AND DISADS OF SEXUAL AND ASEXUAL REPRO
AND ALSO THE ADS AND DISADS OF USING FERTILIZERS
THANKS

Advantages of asexual reproduction in plants:
-Fast/Plants grow more rapidly.

Disadvantages of asexual reproduction in plants:
-More competition between plants.
-They don't colonise new areas.
-Little variation.
-Because there is little variation, if these plants are struck by a disease, none of them may have resistance to the disease which means that they will all probably die.
-Unlikely for future generations to adapt to changes in the environment.

Advantages of sexual reproduction in plants:
-Colonise more areas.
-Less competition between plants.
-More variation.
-Because of increased variation, plants are able to evolve and adapt to changes.

Disadvantes to sexual reproduction in plants:
-Many seeds are wasted because they land in unsuitable places when dispersed.
-Individuals may not be as well adapted to conditions as their parents.
-Require more time than asexual reproduction.

 

[Fatima_Toomii]

both

Advantages of chemical fertilisers:
-Easy to store and add to the land.
-Releases nutrients quickly.
-Shows exactly how much of each nutrient is in the fertiliser.

Disadvantages of chemical fertilisers:
-It can be washed into rivers and streams where it causes water pollution.
-Short-lasting.

Advantages of natural fertilisers:
-They add humus to the soil which improves its structure.
-Lasts for a longer period of time.

Disadvantages of natural fertilisers:
-Farmer doesn't know exact amount of nutrients available.
-Releases nutrients more slowly.

 

[Lost_Life]

Thanks!

 

[Fatima_Toomii]

Thanks!

You're welcome.

 

[Lost_Life]

You're welcome.

 

[Lost_Life]

INSHALLAH WE ALL WILL GET AN A* ameen Ya Rab!