Approximately when did primitive land plants appear?

Which part of an amino acid is the only one that varies and is what defines its properties? A. The amino group B. The R group C. The carboxylic acid group D. The nitrogen base

Which term refers to the large grassland that provides habits for wild flowers wolves rabbit elk deer Bears bison and other plants and animals

True or false " human evolution ended 200,000 years ago when humans (homo sapiens) became a distinct species " justify yout answer in one or two sentences

True or False: In a person's somatic cells, maternal and paternal haplotypesare normally both expressed.

The United States has the most reserves of which fossil fuel? coal petroleum wind

What characteristic of Charales would enable them to survive a dry spell? sperm with flagella phragmoplasts sporopollenin chlorophyll a

Many Head Start programs have a community aide who A. tutors at-risk children in the home. B. gives families the money they need to survive. C. connects families to community resources they need. D. represents families at family/teacher conferences.

Stranded on an island, you have two sources of water to drink: salty ocean water and contaminated fresh water. explain your choice of drinking water and indicate why your selection is the best choice.

How are a hypothesis a prediction and an experiment related

Two species of garter snakes live in the same geographic area. One lives mainly in water and the other mainly on land; therefore, they rarely encounter each other and do not interbreed. What type of isolation is this?