Chromosomes contain the genetic information of an organism. Fruit flies reproduce by sexual reproduction. Most of the cells of a fruit fly have 8 chromosomes. Which statement best explains the source of the chromosomes in a normal fertilized fruit fly egg?
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OPTIONS:
- The egg cell contains all 8 chromosomes.
- The sperm cell contains all 8 chromosomes.
- The sperm cell provides 4 chromosomes and the egg cell provides 4 chromosomes.
- The egg cell provides 4 chromosomes and 4 sperm cells each provide 1 chromosome.

The sperm cell provides 4 chromosomes and the egg cell provides 4 chromosomes.

A toy car rolls at a constant speed down a straight inclined track. When the car reaches the flat surface at the base of the inclined track, the speed of the car decreases. Which statement best explains why the speed of the car decreases when it reaches the flat surface?
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OPTIONS:
- The force of gravity acting on the car increases.
- The force of gravity acting on the car decreases.
- The forces influencing the car are not balanced.
- The forces influencing the car are balanced.

The forces influencing the car are not balanced.

Extinction of a species is most likely to occur as a result of
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OPTIONS:
- evolution
- migration
- selective breeding
- environmental changes


environmental changes