Why do humans need both red and white blood cells

An element has 13 protons, 12 neutrons, and 13 electrons. What is the atomic charge? (Hint: is it positive, negative, or neutral)

Weather maps use isobar lines to show weather conditions. Which of the following information is indicated by these lines? A: high and low-pressure areas B: high and low temp C: precipitation level D: cloud formation

Rem sleep is paradoxical because: a. the skeletal muscles remain active, but the brain is inactive. b. the brain is less active than it is during other sleep stages. c. the brain is active, but the major skeletal muscles are paralyzed. d.

Which statements describe processes involved in the accretion of planetesimals and protoplanets? Check all that apply. Both involve the melting of solid materials in the nebula. Both involve the formation of solid particles from nebular materials.

Explain why animals must eat but plants don't eat

What dose the leftover of the exploded star produce

A genus is a taxonomic contains serveral

In selective breeding, organisms with desired traits are chosen to be parents of the next generation. Select one: True False

What is similar between mitosis, meiosis and binary fission

What cellular components do some bacterial cells have that make them powerful pathogens?