CELLS (II)
Interaction function
Reproduction function
Scientifics
Types of responses
Cell movement
These changes are known as stimuli. Stimuli can be chemical or physical
It is the capacity to capture changes and respond to them correctly
Flagellar movement: It is produced in cells that have flagella
Contractile movement: is characteristic of muscle cells, which are able to contract and relax
It's closely linked with the cytoskeleton, organelle which enable the cell to move with its contractile structures
Amoeboid movement: is characteristic of amoebas. In order to move, amoebas send out protrusions of cytoplasm from anywhere on their surface
It takes place in
How cells divide
Is the process by which a parent cell divides in two or more identical cells called daughter cells. Is called cell division
Types of cell division
Budding: The parent cell divides into two daughter cells, one of which develops a small bud on the other. This is how unicellular fungi divides
Spores: the parent cell forms daughter cells with the form of spores, which are kept inside until the membrane crusts.
Fission: The parent cell divides into two daughter cells of the same size. Most of the human cells divide this way.
Schleiden and Schwann: Schleiden concluded that plant tissues were made up of cells and Schwann expanded this theory to animals and said cells were the basic unit of life
Virchow: he said "all cells come from other cells.
Brown: discovered the nucleus while studying plant cells
Ramón y Cajal: He studied nervous tissues and proved that nuerons are the anatomical and functional unit of the nervous system
Hooke: he was the first person to use a microscope with several lens and he discovered tiy cells observing cork
Margullis: she developed a theory promoting that eukaryotic cells have their origin in prokaryotic cells
Leeuwenhoek: He discovered small living things in pond water using a microscope developed by himself.
Cell theory
Cells are the functional units of all living things
Cells are the origin of all living things
Cells are the strictural units of living things
Static: there is no movement produced rather the cell responds in a different way
Dynamic: the cell responds by moving. They can be positive or negative
Multicellular organisms: cell division enbales the organism to increase its size and to replace the cells in the body that die off
DNA replication: the duplication of hereditary information. The DNA must be equally distributed so the daugfhter cells have the same amount of hereditary information
Cytoplasm division: the distribution of contents of the parent cell among the daughter cells. It doesn't need to be equal.
Unicellular organisms: the object of cell division is reproduction