I need Multiple choice help on Biology please .?

Question

7. The unit of measurement that scientists use to determine the diameter of an animal cell is the

A. millimeter.
B. micrometer.
C. nanometer.
D. meter.


8. Which one of the following statements accurately describes an enzyme?

A. It causes chemical reactions to occur faster.
B. It's broken down into sugar as it performs its job.
C. It functions as a stabilizing molecule.
D. Its main job is to keep reluctant molecules separated.


9. If you were a plant that wanted to use sunlight to make glucose, which set of additional raw materials would you require?

A. Oxygen and carbon dioxide
B. Energy and water
C. Carbon dioxide and water
D. Oxygen and energy


10. When mitochondria burn sugar in the process called respiration, one of the by-products is

A. starch.
B. ATP.
C. chlorophyll.
D. glucose.

Answer 1

7 - B. The typical diamater of a cell is 10 micrometers.

8 - A. An enzyme is a catalyst, which means it lowers the activation energy of the reaction, causing it to proceed faster. The enzyme may react briefly with the reactants, but is not consumed in the reaction (i.e. there's the same amount of enzyme at the end as there was before the reaction started).

9 - C. Plants use energy from the sun and carbon from carbon dioxide to make glucose. They also need water to supply electrons in an early stage of photosynthesis.

10 - B. I'm not sure "by-product" is quite the right word as it is the desired product, but ATP is the only one of those four compounds during any stage of celluar respiration. Starch can be broken down into glucose, and glucose is the sugar that is burned during cellular respiration. Chlorophyll is found in plants and is involved in photosynthesis, but has no role in cellular respiration.

Answer 2

nanometer
It causes chemical reactions to occur faster.
Carbon dioxide and water
glucose.