| Cards | 10 |
| Topics | Cambrian Period, Classification of Life, Curved Lenses, Electromagnetic Spectrum, Fats, Force, Health Benefits of Vitamins & Minerals, Number System, Power, Stratus Clouds |
The Cambrian period is one of the most significant geological time periods. Lasting about 53 million years, it marked a dramatic burst of changes in life on Earth known as the Cambrian Explosion. It is from this period that the majority of the history of life on Earth, as documented by fossils, is found. Called the fossil record, the layering of these mineralized imprints of organisms preserved in sedementary rock have allowed geologists to build a historical record of plant and animal life on Earth.
Classifications of life are too numerous to enumerate, here's an overview of the classifications from broadest to narrowist:
| Classification | Contains Related |
|---|---|
| Kingdom | phyla |
| Phylum | classes |
| Class | orders |
| Order | families |
| Family | genera |
| Genus | species |
| Species | organisms |
Unlike curved mirrors that operate on the principle of reflection, lenses utilize refraction. A convex lens is thicker in the middle than on the edges and converges light while a concave lens is thicker on the edges than in the middle and diffuses light. A common use for curved lenses is in eye glasses where a convex lens is used to correct farsightedness and a concave lens is used to correct nearsightedness.
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.
Like carbohydrates, fats provide energy to the body. The difference is energy from fats tends to be longer burning as opposed to the quick fuel provided by carbohydrates. Fats come in three types, saturated (meats, shellfish, eggs, milk), monounsaturated (olives, almonds, avocados), and polyunsaturated (vegetable oils). Saturated fats can raise LDL ("bad") cholesterol while unsaturated fats can decrease it.
Force is applied to change an object's speed or direction of motion.
| 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. |
The metric system is a number system that designates one base unit for each type of measurement. For example, the base unit for length is the meter and the base unit for mass is the gram.
Power is the rate at which work is performed or work per unit time: \(P = {w \over t}\) and is measured in watts (W).
Clouds are categorized based on their shape, size, and altitude. Stratus clouds are low-altitude clouds characterized by horizontal layering with a broad flat base. When stratus clouds occur on the ground the result is fog.