Question

which of the following correctly compares the structures of plant and animal cells?
a both plant and animal cells have a large central vacuole where enzymes, nutrients, and waste are stored.
b both plant and animal cells have ribosomes which synthesize proteins for the cell.
c both plant and animal cells have a nucleus where cellular respiration takes place.
d both plant and animal cells have cell walls which transport substances into and out of the cell.

question 12 (2 points)
(02.02 mc)
which of the following outcomes would be most likely if the membrane of a cell were to no longer be selectively permeable?
a harmful substances would be able to enter the cell and cause mutations to the cells dna.
b the cell would grow as more nutrients would be able to easily enter the cell.
c a cell wall would form outside the membrane to protect the contents of the cell.
d the cell would die as it would not be able to regulate which substances can enter and leave.

question 13 (2 points)
(02.02 mc)
when plants with soft stems and leaves begin to droop, what is going on inside the plant cells that causes plants to droop like this?
a the cell membranes begin to come apart when there is not sufficient water around the cells.
b the cytoplasm of the cells becomes more concentrated, which slowly poisons the cells.
c the cell walls become brittle as they dry out, and some of them collapse.
d the central vacuoles in the cells lose water and can no longer help support the cells.

question 14 (2 points)
(02.03 mc)
why is it important that the inside of a lysosome have a lower ph than the surrounding cytoplasm in the cell?
a the protein molecules constructed in the lysosome form best at a lower ph.
b the substances stored in a lysosome are most stable at a lower ph.
c the digestive enzymes in the lysosome work best at a lower ph.
d the waste products stored in the lysosome require a lower ph.

Explanation:

1. For the first question about plant and animal cell structures: Plant cells have a large central vacuole, animal cells don't always have a large central vacuole; ribosomes are present in both plant and animal cells for protein - synthesis; cellular respiration mainly occurs in mitochondria, not the nucleus; plant cells have cell walls, animal cells don't. So the correct statement is that both have ribosomes.
2. For the second question about cell membrane permeability: A selectively - permeable membrane regulates the entry and exit of substances. If it loses this property, the cell can't regulate substances and will die.
3. For the third question about plants drooping: When plants droop, the central vacuoles in plant cells lose water and can no longer support the cells well.
4. For the fourth question about lysosome pH: Lysosomes contain digestive enzymes that work best at a lower pH.

Answer:

1. b. Both plant and animal cells have ribosomes which synthesize proteins for the cell
2. d. The cell would die as it would not be able to regulate which substances enter and leave
3. d. The central vacuoles in the cells lose water and can no longer help support the cells
4. c. The digestive enzymes in the lysosome work best at a lower pH