Bacteria, a prokaryote, has circular DNA, as do mitochondria and chloroplasts. This provides support for the Endosymbiotic Theory, which states that the mitochondria and chloroplast in eukaryotic cells were once aerobic bacteria (prokaryote) that were ingested by a large anaerobic bacteria (prokaryote).
About half of a body’s weight is muscle. Muscle tissue is of three distinct types: skeletal, cardiac, and smooth. Each type has a unique structure and a specific role. Skeletal muscle<span> moves bones. </span>Cardiac muscle<span> contracts the heart to pump blood. The </span>smooth muscle<span> tissue that changes shape to facilitate bodily functions of intestine and bladder. Here are more details about the structure and function of each type of muscle tissue in the human muscular system. </span>
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.
