ASVAB General Science Practice Test 994112

Questions 5
Topics Biosphere, Cell Membrane, Health Benefits of Vitamins & Minerals, Lungs, Moon

Study Guide

Biosphere

The biosphere is the global ecological system integrating all living beings and their relationships. This includes their interactions with the lithosphere (the rigid outer part of the earth, consisting of the crust and upper mantle), hydrosphere (all surface water), and atmosphere (the envelope of gases surrounding the planet).

Cell Membrane

Animal cells are surrounded by a semipermeable membrane which allows for the transfer of water and oxygen to and from the cell. In plant cells, the cell membrane is surrounded by a somewhat rigid cell wall which provides the cell structure and support.

Health Benefits of Vitamins & Minerals
Vitamin / Mineral Sources Health Benefits
Calcium Dairy products (milk, yogurt, cheese), spinach. Aids bone growth and repair, muscle function.
Iron Red meat, beans, whole grains. Allows red blood cells to transfer oxygen to body tissues.
Magnesium Nuts, whole grains, green leafy vegetables. Muscle, nerve, and enzyme function.
Potassium Bananas, nuts, seeds. Helps balance fluid levels in the body.
Vitamin A Liver, milk, eggs, carrots. Vision, immune system, cell growth.
Vitamin C Green and red peppers, citrus fruits, broccoli. Collagen formation, immune system function, antioxidant (helps protect cells from damage).
Vitamin D Exposure to sunlight. Helps calcium strengthen bones, muscle, nerve, and immune system function.
Lungs

The trachea branches into the left and right bronchi which each lead to a lung where the bronchi subdivide into smaller tubes called bronchioles. Each bronchiole ends in a small sac called an alveolus which allows oxygen from the air to enter the bloodstream via tiny blood vessels called capillaries.

Moon

Tides are caused by the gravitational interaction of Earth and the Moon.