How does the structure of a cell membrane the cell regulate water

An example of internal feedback working to maintain homeostasis is your a. decreased respiration rate when you are studying b. decreased heart rate when you are sad c. increased respiration rate when your muscles need more oxygen d. increased heart rate when your lungs need more oxygen

How do all types of diffusion/passive transport actually ‘work’ without using even the smallest amount of cellular energy?

Apopulation of bears has genetic diversity. some of the bears have an allele that gives them thicker fur. due to climate change, the winters have gotten colder in their habitat. now the bears with thicker fur are becoming more common in the population. a.) which type of bear is selected for in the coldest ecosystem? b.) what must be the other allele for the type of fur, and what term would you use to describe the fact that the allele is becoming less common in the colder climate? c.) describe the change in the bear population in terms of changing allele frequencies and phenotypes d.) is this an example of natural selection