General Science Flash Card Set 307282

Cards 10
Topics Acceleration, Acidity, Cell Energy, Electromagnetic Spectrum, Endoskeleton, Frequency, Health Benefits of Vitamins & Minerals, Magnetism, Nucleus, Solid

Study Guide

Acceleration

Newton's second law of motion leads to the formula for acceleration which is a measure of the rate of change of velocity per unit time and, if you solve for positive acceleration, reveals how much net force is needed to overcome an object's mass. The formula for acceleration is \(\vec{a} = { \vec{F} \over m }\) or, solving for force, \(\vec{F} = m\vec{a}\).

Acidity

An acid is a substance that gives up positively charged hydrogen ions (H+) when dissolved in water. A base (alkaline) gives up negatively charged hydroxide ions (OH-) when dissolved in water. pH is a scale that measures of how basic or acidic a solution is. Numbered from 0 to 14, solutions with a pH of 7 are neutral, less than 7 are acidic, more than 7 are alkaline.

Cell Energy

Some plant cells produce their own energy through photosynthesis which is the process by which sunlight, carbon dioxide, and water react to make sugar and oxygen. Animal cells cannot produce their own energy and, instead, generate energy when mitochondria consume outside sugar and oxygen through aerobic respiration.

Electromagnetic Spectrum

The electromagnetic spectrum covers all possible wavelengths and frequencies of radiation. From lowest frequency (longest wavelength) to highest frequency (shortest wavelength) radiation: radio waves → microwaves → infrared waves → visible light → ultraviolet light → X-rays → gamma rays.

Endoskeleton

An endoskeleton (internal skeleton) is a charateristic of vertebrate animals, including humans.

Frequency

The rate of vibration of sound is called frequency and is measured in hertz (Hz). One hertz is one repetition per second and sounds with high frequency have a higher pitch than sounds with lower frequency. Humans can hear sounds in the range of 20 Hz to 20 kHz.

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.
Magnetism

Simple magnets have two poles, north and south, and opposite poles attract each other (N attracts S, S attracts N). Likewise, the same pole of two magnets repel (N repels N, S repels S). The Earth has a magnetic field and North and South Poles which enables the use of a magnetic compass to determine direction.

Nucleus

Cells are classified into one of two groups based on whether or not they have a nucleus. Eukaryotic cells have a nucleus, prokaryotic cells do not have a nucleus and therefore have a less complex structure than eukaryotic cells.

Solid

An element in a solid state has atoms or molecules that are constricted and do not move freely. Solids maintain a constant volume and shape and exist at a lower temperature than liquids or gases.