Problem: OPTIONS:
- overpopulation
- accumulation
- evolution
- extinction
Q: Q: Warming conditions and, perhaps, human activities contributed to what fate of many organisms of the pleistocene era? A:
Answer: extinction

Problem:OPTIONS:
- hibernation, thick fur
- colourful fur , blubber
- camouflage, blubber
- thick fur, blubber

Q: What 2 things keep polar bears warm in their arctic ecosystem? A:
****
A: thick fur, blubber

Q: What is the rising and sinking of warm and cooler material called? A:
OPTIONS:
- depression
- conveyance
- diffusion
- convection
convection

Q: The first line of defense includes mechanical, chemical, and which other barrier? A:
OPTIONS:
- independent
- physical
- surgical
- biological

Answer: biological

Question: Q: What is the large muscle that extends across the bottom of the chest below the lungs called? A:
OPTIONS:
- uterus
- pectoral
- abdomen
- diaphragm
Answer: diaphragm

input: OPTIONS:
- lipids
- protons
- hormones
- proteins Now, answer this question: Q: What is the name for biochemical compounds that consist of one or more chains of small molecules called amino acids? A:
A:
output:
proteins