Answer:
1. import and export of nutrients and wastes
2. cell signaling
3. cell recognition
4. cell growth and motility
Explanation:
Plasma membranes are selectively permeable which means it only allows selective molecules to cross through it. So the plasma membrane helps in the import and export of nutrients by simple diffusion, facilitated diffusion or through active transport.
There are membrane protein embedded in the plasma membrane which have different role. Some help in cell signaling like GPCR, some help in cell recognition and some act and transporter proteins.
The plasma membrane is also responsible for cell growth and motility because it allow the raw materials and signals to pass through it which is required by the cell to metabolize and grow. So 1,2,3,4 is the correct answer.
Diffusion is the passive transport from a high concentration to a low without using energy. homeostasis results from balance.
Answer:
ureters
Explanation:
The ureters are two tubes that drain urine from the kidneys to the bladder. Each ureter is a muscular tube that drains into the bladder. Smooth muscle contractions in the walls of the ureters, over time, send the urine in small spurts into the bladder, the organ where urine is stored before it can be eliminated.
Answer:
Squirrels will emigrate and leave the population.
Explanation:
Hope this helps
The answer is <span>Take consistent amounts of saliva samples from a number of people who have not eaten in 8 hours and measure the quantity of amylase in each sample.
First, the researcher needs to know the quantity of amylase in the <u>same</u> amount of saliva. Thus the amount must be consistent and not varying.
Next, people must not eat in 8 hours, so they are all in the same condition at the moment of collecting saliva. If some eat immediately before the sample collecting while some eat 8 hours before, the content of their saliva will be different.
For the correct results, all conditions must be the same.</span>