1. What is the first line of defense against infection for the human body?

A. white blood cells

B. saliva

C. skin

D. red blood cells

What type of catastrophic event, which left a slight crater in the Yucatan Peninsula and iridium rich soil nearby, is thought to have possibly caused the extinction of the dinosaurs?

What is the colorless fluid surrounding the grana within the chloroplast.

Which of the following statements about desalination is true? a) desalination is less expensive than water reclamation. b) desalination uses large amounts of energy.

1. Describe deforestation. 2. List one cause of deforestation and the effect associated with that cause. 3. Describe urbanization. 4. List one cause of urbanization and the effect associated with that cause. 5. Describe desertification. 6.

One difference between a cancer cell and a normal cell is that a. cancer cells divide uncontrollably. b. normal cells divide uncontrollably. c. cancer cells cannot make copies of dna. d. normal cells cannot make copies of dna.

Define trawling, and explain the ecological damage associated with it.

Which stimulus would a flatworm be able to detect The color of a predator The feel of an approaching rainstorm The sound of splashing water The smell of prey

How are fish adapted to thier enviroment?

This is a type of protein found in a cell membrane which regulatesthe coming and going of substances into or out of the cell

Competition over resources occurs between organisms