What is the name of the neurotransmitter that excites muscle cells (causes them to contract) ?

Which of these is an example of natural selection? A: decrease in the height of tomato plants over one generation B: penguins migrate farther than their parents to hunt for fish due to climate change C: puppies having a different color coat than

What structure lies on top of the kidney?

Select all that are chordates. (1) fish (2) mammals (3) birds (4) amphibians (5) reptiles

Water, or H2O, is a covalent substance because there is a covalent bond between -

Which issue is a basic challenge an organism encountered A) reproducing. B) getting energy C) staying healthy D) all of the above

Melting snow, rain, and storms can all lead to which event?

In your own words, explain what the summary equation tells you about cellular respiration.

What 3 factors determine the size of a wave

What is the back cavity of the mouth where the food is forced

A geneticist observes 10 pairs of homologous chromosomes at metaphase I of meiosis in a newly discovered species of flowering plant. How many chromosomes should be found in a microsporocyte