Cards | 10 |
Topics | Acidity, Base Units, Blood Cells, Cell Division, Cytoplasm, Geologic Time Scale, Nucleus, Prefixes, Producers, Terrestrial Planets |
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.
Measurement | Base Unit | Example |
---|---|---|
length / distance | meter (m) | km |
mass | gram (g) | kg |
volume | liter (L) | mL |
volume (medical) | cubic centimeter (cc) | cc |
time | second (s), minute (min), hour (h) | ms, min, h |
temperature | centigrade (°C) | °C |
Blood is created in bone marrow and is made up of cells suspended in liquid plasma. Red blood cells carry oxygen, white blood cells fight infection, and platelets are cell fragments that allow blood to clot.
Cell division is the process by which cells replicate genetic material in the nucleus. Cell division consists of several phases:
Phase | Major Process |
---|---|
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 |
The nucleus of a eukaryotic cell contains the genetic material of the cell and is surrounded by cytoplasm which contains many organelles. These include:
Organelle | Function |
---|---|
ribosomes | produce proteins |
mitochondria | produce energy |
endoplasmic reticulum | helps synthesize proteins and fats |
Golgi apparatus | prepare proteins for use |
lysosomes | help the cell manage waste |
centrosomes | guide cell reproduction |
The Earth is approximately 4.6 billion years old and its history is divided into time periods based on the events that took place and the forms of life that were dominant during those periods. The largest graduation of time is the eon and each eon is subdivided into eras, eras into periods, periods into epochs, and epochs into ages.
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.
A prefix is added to the base units of the metric system to indicate variations in size. Each prefix specifies a value relative to the base unit in a multiple of 10. Common prefixes are:
Prefix | Symbol | Relative Value | Example |
---|---|---|---|
mega | M | 106 (1,000,000) | Mm |
kilo | k | 103 (1,000) | km |
base unit | N/A | 1 | m |
centi | c | 10-2 (1/100) | cm |
milli | m | 10-3 (1/1,000) | mm |
Producers (autotrophs) serve as a food source for other organisms. Typical producers are plants that can make their own food through photosynthesis and certain bacteria that are capable of converting inorganic substances into food through chemosynthesis
The four planets closest to the Sun (Mercury, Venus, Earth, and Mars) are called terrestrial (Earth-like) planets because, like the Earth, they're solid with inner metal cores covered by rocky surfaces.