Question

1. which of these structures breaks down sugars to provide energy for cell activities?

a. vacuole b. endoplasmic reticulum
c. nucleus d. mitochondrion

1. name one structure found in an animal cell that is not found in a plant cell.

Explanation:

• Question 4: Mitochondrion is the powerhouse of the cell. It breaks down sugars (through cellular respiration) to produce ATP (adenosine tri - phosphate), which provides energy for cell activities. A vacuole stores substances like water, nutrients, and waste. The endoplasmic reticulum is involved in protein and lipid synthesis. The nucleus contains the cell's genetic material and controls cell activities but not directly in energy production from sugar breakdown.
• Question 5: Centrioles are structures found in animal cells that are not present in plant cells (except in some lower - plant forms). Centrioles play a role in cell division by organizing the spindle fibers.

Answer:

• Question 4: D. mitochondrion
• Question 5: Centriole