Which of the following option gives result of the experiment after 24 hours?
The Level of Sugar Solution
Loading image•••
Choices
Choice (4)
a.
D
b.
C
c.
B
d.
A
Answer
b.
Explanation
The level of sugar solution in the potato cavity rises after some time due to the entry of water into the sugar solution through the selectively permeable membrane of the cells of the potato. The movement of water from the Petri dish to the potato cavity occurs because of the difference in the concentration of solvent molecules in the two regions: sugar solution in the potato cavity and pure water in the Petri dish.
Which cell type absorbs the most carbon dioxide during the day?
Plants Get the Carbon Dioxide
Loading image•••
Choices
Choice (4)
a.
C
b.
D
c.
A
d.
B
Answer
b.
Explanation
Plants get the carbon dioxide they need from the air through their leaves. It moves by diffusion through small holes in the underside of the leaf called stomata. Guard cells control the size of the stomata so that the leaf does not lose too much water in hot, windy, or dry conditions.
The lower part of the leaf is a spongy layer with loose-fitting cells. These let carbon dioxide reach the other cells in the leaf, and let the oxygen produced in photosynthesis leave the leaf easily.
