GED Science Life Science 3

Question 1

Which organelle is responsible for producing ATP through cellular respiration in eukaryotic cells?

Accepted Answer

Mitochondria

Answer

Mitochondria are the site of cellular respiration, where glucose and oxygen are converted into ATP energy.

Question 2

A scientist observes that a population of moths shifts from mostly light-colored to mostly dark-colored after industrial pollution darkens tree bark. This is an example of:

Accepted Answer

Natural selection

Answer

Natural selection favored dark moths because they were better camouflaged on soot-darkened trees and survived to reproduce more.

Question 3

Which of the following best describes the role of decomposers in an ecosystem?

Accepted Answer

They break down dead organisms and recycle nutrients

Answer

Decomposers like fungi and bacteria break down dead organic matter, returning essential nutrients to the soil.

Question 4

In a DNA double helix, adenine always pairs with:

Accepted Answer

Thymine

Answer

Adenine pairs with thymine via two hydrogen bonds in DNA, following Chargaff's base-pairing rules.

Question 5

A plant is moved from a sunny window to a dark closet for two weeks. Which change would most likely occur first?

Accepted Answer

Leaves turn yellow due to chlorophyll breakdown

Answer

Without light, the plant cannot produce chlorophyll or use existing chlorophyll, causing leaves to yellow (chlorosis).

GED Practice Test

GED Practice Test

GED Science Life Science 3