|Topics||Asteroids, Blood Flow, Cambrian Period, Cell Division, Classification of Life, Cytoplasm, Electromagnetic Spectrum, Liquid, Meteoroids, Traits|
The solar system also contains over a million rocky fragments of at least 1km in diameter called asteroids as well as millions more with smaller diameters. Many of these asteroids are an asteroid belt between the orbits of Mars and Jupiter.
To provide oxygen to the body, blood flows through the heart in a path formed by the right atrium → right ventricle → lungs → left atrium → left ventricle → body. When blood enters the right side of the heart it is deoxygenated. It enters the left side of the heart oxygenated after traveling to the lungs.
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.
Cell division is the process by which cells replicate genetic material in the nucleus. Cell division consists of several phases:
|interphase||chromosomes replicate into chromatids and the cell grows|
|prophase||chromatids pair up|
|metaphase||paired chromatids move to opposite sides of the cell|
|anaphase||cell elongates and nucleus begins to separate|
|telophase||separation of nucleus is complete resulting in two new nuclei|
|cytokinesis||cytoplasm and cell membranes complete their separation resulting in two separate cells|
Classifications of life are too numerous to enumerate, here's an overview of the classifications from broadest to narrowist:
The nucleus of a eukaryotic cell contains the genetic material of the cell and is surrounded by cytoplasm which contains many organelles. These include:
|endoplasmic reticulum||helps synthesize proteins and fats|
|Golgi apparatus||prepare proteins for use|
|lysosomes||help the cell manage waste|
|centrosomes||guide cell reproduction|
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.
In the liquid state, molecules flow freely around each other and exist at a higher temperature range than the same substance in a solid state. Liquids maintain a constant volume but their shape depends upon the shape of their container.
Smaller rocks shed by asteroids and comets are called meteoroids. When these rocks reach Earth's atmosphere, they burn up in the mesosphere and become meteors. If a meteor manages to reach the Earth, it is called a meteorite.
The traits represented by genes are inherited independently of each other (one from the male and one from the female gamete) and a trait can be dominant or recessive. A dominant trait will be expressed when paired with a recessive trait while two copies of a recessive trait (one from each parent) must be present for the recessive trait to be expressed.