Question

1. where in the cell does respiration occur? *

a) endoplasmic reticulum
b) mitochondria
c) the nucleus
d) chloroplast

1. what is the purpose of having mitochondria in plant cells when they already have chloroplasts? * 1 po

a) to store water
b) to transform energy form sunlight into sugar
c) to transform sugar into energy
d) to store nutrients

1. respiration is a ____________ reaction in which sugar is oxidized to produce energy. * 1 po

a) chemical
b) physical

Explanation:

• For question 2: Mitochondria are the power - houses of the cell and the site of cellular respiration. The endoplasmic reticulum is involved in protein and lipid synthesis. The nucleus contains genetic material. Chloroplasts are for photosynthesis.
• For question 3: Chloroplasts convert sunlight into sugar (photosynthesis). Mitochondria convert sugar (produced by chloroplasts) into energy (ATP) through respiration. Storing water is the function of vacuoles and storing nutrients is not the main function of mitochondria.
• For question 4: Respiration is a chemical reaction as it involves the breaking of chemical bonds in sugar (glucose) and the formation of new substances (carbon dioxide, water) with the release of energy. A physical reaction does not involve a change in the chemical composition of substances.

Answer:

1. B. mitochondria
2. C. to transform sugar into energy
3. A. chemical