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Describe how water is carried by the transpiration stream. (3 marks)

Transpiration is the loss of water from a plant by evaporation, which then diffuses out of the leaf via the stomata. It is important to note whether the student understands how and why water leaves the plant...
AS
Answered by Abishek S. • Biology tutor
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Why are the lungs adapted for the rapid absorption of oxygen into the blood?

Oxygen is absorped into the blood by the process of diffusion. A large surface area, short diffusion pathway (the distance the oxygen has to travel through) and large concentration gradient increases the rat...
CP
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Explain the adaptations of cacti to their environment

Extensive root systems allow for maximum uptake of available water from the ground. Low surface area to volume ratio reduces the rate of evapotranspiration, alongside a thick waxy cuticle covering the surfac...
LB
Answered by Lewis B. • Biology tutor
8768 Views

Sandeep has been fasting and is not drinking water during the daytime. Name the hormone and explain the sequence of events involving this hormone, that occur during the day to maintain Sandeep's water balance.

ADH (Anti-diuretic hormone). First his blood plasma becomes more concentrated. This is detected by receptors in the hypothalamus which stimulates the pituitary gland to secrete ADH. ADH enters the blood stre...
NB
Answered by Nathan B. • Biology tutor
2825 Views

What are the adaptations of alveoli to increase gas exchange?

Alveoli are folded to increase their surface area to volume ratio, so more volume of air can diffuse in from the blood and and in from the bronchioles. The lining of the alveoli walls are also moist so the g...
LB
Answered by Lathesha B. • Biology tutor
79090 Views