Top answers

Explain the passive transport mechanisms across a cell membrane, differentiating between simple diffusion and facilitated diffusion.

Substances move down a concentration gradient in passive transport, meaning that no energy input (ATP) is required. Hydrophilic molecules will pass down the membrane using facilitated diffusion, as they cann...
RP
Answered by Rares P. • Biology tutor
2574 Views

What is the role of receptors in mediating steroids and protein hormones?

Steroid hormones are lipids; they can cross directly through the cell's plasma membrane and nuclear membrane, binding to receptors. Receptor – hormone complex is formed and serves as a transcription factor; ...
RP
Answered by Rares P. • Biology tutor
3482 Views

Describe homoeostasis using temperature control as an example.

Homeostasis is the maintenance of a constant internal environment. The body tends to use a series of negative feedback loops to allow this. Using temperature as an example, the body likes to maintain a core ...
PS
Answered by Priya S. • Biology tutor
4074 Views

State the difference between a malignant and benign tumor is and describe how tumors form

Malignant tumors are cancerous, harmful tumors whereas benign are non-cancerous. Tumors are caused by a mutation which causes uncontrolled cell division.
EW
Answered by Esther W. • Biology tutor
5951 Views

A biologist has a small pond containing goldfish in her garden. On a sunny day, more pondweed is at the surface of the water but on a cloudy day, less pondweed is at the surface. Suggest an explanation for this observation

The intensity of light is greater on a sunny day, therefore the rate of photosynthesis in the pondweed is greater during these days. Hence, more oxygen is produced which thereby increases the bouyancy (makes...
JS
Answered by Jay S. • Biology tutor
7934 Views