Peridotite, which is composed almost entirely of dark silicate materials and is believed to make up much of earths upper mantle, has a composition that is

A new island forms due to an underwater volcano. Birds from the mainland colonized the island. This is an example of a. Behavioral isolation b. Reproductive isolation c. Geographic isolation

What can you conclude about an ecosystem with many trophic levels? A. It is an unhealthy ecosystem. B. It is a stable ecosystem C. It has very few producers. D. It has no tertiary consumers.

In the 1600s, which scientist discovered microbes in pond water by using a microscope? A. Theodor Schwann B. Robert Hooke C. Anton van Leeuwenhoek D. Matthias Schleiden

What is the importance of stem cells within human bodies? Choose all that apply. Plants are the only type of organisms that contain stem cells-located in the stems and roots.

Describe at least one societal issue that scientists will be able to address using the sequence of the human genome.

Explain how the following modifications to cell structure could increase efficiency of materials exchange between the cell and its environment: The cell is thin and flat The cell has extensions such as cilia on its membrane The cell uses vesicles to

Three of these processes normally consume oxygen. Which process produces oxygen? A) combustion B) respiration in animals C) photosynthesis in plants D) operation of an acetylene torch

Why is membrane more permeable to potassium?

What is the difference between white and red blood cells apex?

LaKeisha stepped on a piece of glass and quickly pulled her foot away from that sharp object. Which of the following are responsible for sending a message to the muscles in LaKeisha's foot, resulting in her pulling her foot away from the piece of