What characteristics of organisms older than 540 million years ago makes fossils?

Define homozygous Define heterozygous.

What does a scientific theory do

Review the desert food web above. what organism, absent in the web, would be most responsible for recycling organic matter back through the food web

Explain the factors and interactions related to energy in an ocean's food chain

Which of the following best describes homeostasis in humans? a. homeostasis continues when environments change. b. homeostasis stops when external environments change. c. homeostasis halts when internal environments d.

Imagine that you want to breed a species of rose that has a wonderful smell. You have many different types of roses, but none of the individual roses has the wonderful smell that you want.

Which term refers to contrasting forms of the same gene

As a mouse undergoes respiration, it produces lactate. This type of respiration can be classified as acidic alcoholic aerobic anaerobic

Which continent lies almost completely within the tropical zone?

Which phrase best summarizes the theory of evolution by natural selection? a. Only the strongest animals survive. b. Life must come from other life. c. Populations change over long periods of time. d.