Which of the following is hypothesized to be the early source of free oxygen in Earth's atmosphere? A. photosynthesis by cyanobacteria B. ionization of water molecules C. respiration of fish D. decay of animal remains

How does the nucleus controls cell? Be specific

What makes up muscle tissue A organs B cells C organisms D organ Systems

What do the brackets around a chemical mean, like for [h + ]?

True or false. Most of the DNA in the human genome codes forgenes.

Living thing composed of more than one cell

Which statement best describes the relationship between activation energy and rate of reaction? O Increasing the activation energy can increase the rate of a reaction. O Reducing the activation energy can increase the rate of a reaction.

Definition: this is a haploid cell with half the reproductive information from the parent.

Does a cell use energy when molecules diffuse in or out of the cell? Why?

Below is a list of possible challenges. Check all errors that you mentioned in your answer. Traits other than beak type might affect natural selection. It could take many generations to observe adaptions to a population.

A farmer dug a well but did not find any water Which reasons most likely explain why the farmer did not find water? Check all that apply.