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.
Answer: parasitism
Explanation: Because it's relationship between two species of plants or animals in which one benefits at the expense of the other, sometimes without killing the host organism.
Answer: Base pairs occur when nitrogenous bases make hydrogen bonds with each other.
Explanation: Each base has a specific partner: guanine with cytosine, adenine with thymine (in DNA), The hydrogen bonds are weak allowing it to "unzip"
3 is a
7 is b hope I helped