Which of the following is the best description of natural selection?

The struggle to exist.

The change in variation of a species.

Survival of the fittest.

Overproduction of offspring

How does oxygen enters the blood and is transported to the cells

Sperm cells contain many more mitochondria than most other types of cells. Why do you think sperm have such a large number of mitochondria?

What is the body system that controls growth and metabolism, and regulates reproduction, through hormones?

Which of the following is a natural cause of carbon increases and decreases? Question 2 options: clearing of land for new development collecting and burning natural gas plant growth related to weather water usage related to fires

quiizlet A friend of yours has gone out on a warm day for a relatively long jog. She has taken along water to drink. After about an hour the water is gone, but your friend continues on for another 30 minutes.

In everyday life, a theory is an educated guess. In science a theory is

How can invasive species result in changes in other populations?

the classes are playing tug of war. Mrs. Larson's homeroom pulls with a force of 50N. Ms. Mitko's homeroom pulls with a force of 45 N in the opposite direction. What is the net force? And who won?

The synaptic cleft is the area between the a. soma of one neuron and the dendrite of another neuron. b. axon of one neuron and the dendrite of another neuron. c. axon of one neuron and the soma of another neuron. d. somas of two neurons.

When the blades of a fan move, they have mechanical energy. This mechanical energy comes from A. electrical energy flowing into the fan from the wall outlet. B. sound energy flowing into the fan from a radio. C.