Question

17.microtubules
a. provide shape and movement for cells.
b. transport materials throughout the cytoplasm.
c. convert chemical energy to electrical energy.
d. are artificial structures produced using nanotechnology.
e. none of the above.

18.the pressure exerted against the cell membrane and cell wall is known as
a. wall pressure.
b. turgor pressure.
d. cell pressure.
c. negative pressure.
e. none of the above.

19.a plant vacuole serves as a storage space for
a. water.
b. sugars.
d. proteins.
c. minerals.
e. all of the above.

20.which of the following is not necessary for a plant to perform photosynthesis?
a. carbon dioxide
b. water
d. minerals
c. sunlight
e. sugar

1. plant cell walls are primarily composed of

a. starch.
b. pectin.
d. cellulose.
c. protein.
e. chlorophyll.

22.after making a wet mount slide to study a cell, you notice an air bubble under the cover slip. what should be done to remove it?
a. squeeze the slide between your thumb and forefinger
b. add gas - line antifreeze to absorb the bubble
c. put a piece of paper towel beside the slide to remove the water
d. tap gently with a pencil eraser
e. nothing can remove bubbles

23.animal cells must obtain energy from chemical sources because they do not have
a. lysosomes.
b. mitochondria.
d. chloroplasts.
c. chromoplasts.
e. cell walls.

24.tissue cultures are
a. groups of cells grown out of the body.

Explanation:

Question 17

Microtubules are part of the cytoskeleton. They help in cell shape maintenance and cell movement (like in cilia/flagella), and also assist in intracellular transport. Option c is wrong (they don't convert chemical to electrical energy), d is wrong (they are natural cell structures). So a and b are correct? Wait, no—wait, microtubules: function includes providing shape, movement (like in mitotic spindle, cilia), and transporting materials (via motor proteins). But the options: a says "provide shape and movement for cells"—correct. b says "transport materials throughout the cytoplasm"—also correct? Wait, but maybe the question has a single best answer. Wait, maybe the intended answer is a? Wait, no, let's recall: Microtubules are involved in cell structure (shape), cell movement (e.g., cilia), and intracellular transport (like moving vesicles). But maybe the options: a is about shape and movement, b about transport. Wait, maybe the answer is a? Wait, no, maybe the question's options: let's check again. Option a: provide shape and movement for cells. Option b: transport materials throughout the cytoplasm. Both are functions of microtubules. But maybe the question considers a as more primary? Wait, no, maybe the answer is a? Wait, no, perhaps the intended answer is a. Wait, but maybe I made a mistake. Wait, microtubules: the cytoskeleton (microtubules, microfilaments, intermediate filaments) provides structural support (shape) and enables movement (like in cell division, cilia). Also, they are involved in intracellular transport (like kinesin/dynein moving organelles). So both a and b are correct? But the options are a, b, c, d, e. Wait, maybe the question has a typo, but assuming the options: let's see, option c is wrong (energy conversion is mitochondria/chloroplasts), d is wrong (natural structures). So between a and b. Wait, maybe the answer is a? Or b? Wait, maybe the intended answer is a. Alternatively, maybe the answer is a. Let's go with a.

Turgor pressure is the pressure exerted by the cell contents (vacuole with water) against the cell membrane and cell wall in a plant cell. Wall pressure is the pressure exerted by the wall on the cell, but the pressure against the wall is turgor pressure. So option b is correct.

Plant vacuoles store water, sugars, minerals, and also proteins, pigments, etc. So they store all of the above. So option e is correct.

Answer:

a. provide shape and movement for cells.

Question 18