Natural selection chooses which variations become prevalent in a population through environmental pressures. Which of these is an environmental pressure which can lead to natural selection?

What time frame best describes when earthquakes occur? a. Daily b. Monthly c. Yearly d. Quarterly

The single factor tested in an experiment is

What is the type of non-living material that is enclosed in a protein coat and the coat has spike-like projections all over its surface?

How could serfs move up from the bottom of the social hierarchy? a) Most peasants were also serfs. b) Serfs were always below peasants in the medieval hierarchy c) Serfs worked in the manor house, and peasants worked on the land.

Which region of the highlighted organ prolongs and amplifies the sympathetic (emergency) response?

How would an object blocking a bronchus affect its airflow?

Mary is campaigning for improved air quality in her city. She is very concerned about carbon and methane outputs, but not phosphorous. Why is that? A. She thinks phosphorous makes a positive contribution to air quality, B.

Huntington's disease is a genetic disorder that is caused by a dominant allele. Which of the following is true? A. A person with Huntington's disease will pass the disease onto 100% of their children. B.

Avery could barely detect sweetness in a sip of water from a pitcher in which one quarter of a teaspoon of sugar was mixed into a half gallon of water. for taste, this is avery's:

Flexor muscles are named based on which aspect of the muscles? action location size shape