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Anatomy
Anatomy-unit 3
Question | Answer |
---|---|
cell | the basic unit of all life forms |
Anton Van Leeuwenhoek | dutch drapemaker who was the first to use the microscope to observe nature, bacteria, blood cells, and sperm cells |
Robert Hooke | English sientist who observed cork cells in 1665 and coined the term "cell" |
Matthias Scleiden | German botanist who concluded that all plants are made of cells in 1838 |
Theodore Schwann | German zoologist who concluded that all animals are made of cells in 1839 |
Rudolf Virchow | German physician who concluded that all cells are created from preexisting cells |
Cell theory | 1. All living things are composed of cells 2. cells are the basic unit of structure and function in living things 3. new cells are produced from existing cells |
cell size | a typical cell is from 5 to 50 micrometers |
cells and tissues | tissues are groups of cells that are similar in structure and function-structure reflects function |
anaomy of the generalized cell | cells are not all the same, all cells share a general structure, cells are organized in 3 parts 1. nucleus 2. cytoplasm 3. plasma membrane |
Prokaryotic cells | cells that lack a nucleus and membrane bound organelles, ex. bacteria |
eukaryotic cells | cells that have a nucleus and membrane bound organelles ex. plants, animals, fungi, protista |
The nucleus | acts as the control center of the cell that contains genetic material (dna) |
Nuclear membrane | the barier of the nucleus, which contains nuclear pores, used in the exchange of materials with the rest of the cell (semipermeable membrane) |
nucleolus | nucleus contains one of more nucleoli, site of ribosomal until assembly, and contains DNA and RNA |
chromatin | composed of DNA and protein, scattered throughout the nucleus (when cell divides chromatin condenses to form chromosomes when the cell divides |
chromosomes | DNA and Protein in a coiled rod shaped form during cell division |
plasma membrane | double phospholipid layer (fat and water) with two separate ends. One is hydorphobic, water fearing, and the other is hydropholic, water loving |
cell membrane functions | 1. sepatation of cytoplasm from extracellular fluid 2. regulates exchange of materials 3. structural support 4. sensitivity to changes in the concentrations of carious fluids |
proteins in the cell membrane | 1. regulate ion passageways 2. act as carrier molecules 3. bind to ligands |