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Biology Support Forum (any questions may be asked) (3 Viewers)

el_manu

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Anyone know if this dot point is tested often, "describe current theories about processes responsible for the movement of materials through plants in xylem and phloem tissue"
 

gada1

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How do you know if a species is ectothermic or endothermic?
Hello. Do not listen to Queenroot. If you say that endothermic is warm blooded and ecto is cold blooded, you will get zero. Biology teachers HATE that explanation.
An endothermic organism is one that maintains a relatively constant internal body temperature despite the changes in ambient temperature. They have the metabolic and physiological adaptations that allow them to do so.
An ectothermic organism, however, experiences a fluctuation in internal body temperature which corresponds to the changes in ambient temperatures as they do not have the physiological adaptations that would have enabled a constant internal temperature. Instead, they ONLY depend on behavioural adaptations to regulate changes in internal temperature and to prevent dramatic changes in the conditions of the internal environment.
 

gada1

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Anyone know if this dot point is tested often, "describe current theories about processes responsible for the movement of materials through plants in xylem and phloem tissue"
Yes. These theories are important. Do you need me to explain them? :)
 

gada1

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Hi.
I'm doing an assignment about radioactive tracers travelling through xylem and I have a question which is not even part of the assignment but would help my understanding of the concept.

If water is needed for photosynthesis, why does it evaporate through the stomates?
I thought photolysis occurred so how is there any water left to evaporate?

Thank you
Hello. Don't listen to Queenroot.
Xylem is made of dead tissue. So the transport of water relies on the physical forces of cohesion, adhesion and tension to be transported to all cells for photosynthetic processes to take place.
To answer your question you need to understand the 'tension' concept. Tension is formed within the xylem vessels when the removal of water through the stomata via transpiration forms a concentration gradient of water between the stomata and the xylem vessel. The water is released through the stomata BECAUSE of this concentration gradient that is formed. So the water that HAS NOT BEEN USED in photosynthesis is able to move down this concentration gradient to the stomata and finally into the surrounding environment.
 

Queenroot

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Hello. Do not listen to Queenroot. If you say that endothermic is warm blooded and ecto is cold blooded, you will get zero. Biology teachers HATE that explanation.
An endothermic organism is one that maintains a relatively constant internal body temperature despite the changes in ambient temperature. They have the metabolic and physiological adaptations that allow them to do so.
An ectothermic organism, however, experiences a fluctuation in internal body temperature which corresponds to the changes in ambient temperatures as they do not have the physiological adaptations that would have enabled a constant internal temperature. Instead, they ONLY depend on behavioural adaptations to regulate changes in internal temperature and to prevent dramatic changes in the conditions of the internal environment.
endothermic would be the one with a limited temperature range and can undergo thermoregulation hence it would be 34-36 degrees. Ectothermic would vary with the environment hence it would be the one with a much larger and variable range 8-26 degrees.
Nigga pls
 

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