Biology, Basic Key Terms

Biology Notes

Cell theory: All living things are composed of cells or cells products existing cells divide to produce new cells

Cell membrane: Isolate the inside of the cell from the outside environment

Organelles: Structures within in the cell, have specific functions

Nucleus: Contains DNA-chromosome and RNA which contain protein synthesis

Cytoplasm: All contents excluding the nucleus

Eukaryotic: Contains DNA and nucleus- includes plant and animal cells

Prokaryotic: DNA scattered, simple strucre no organelles

Movement of chemical in and out of the cell

A cell memebrane is semipermeable. Which allows certain

substances to pass through.

Passive transport: No energy

 Materials travel from low to high concentrations

Active transport: requires energy

 Transports material , high to low concentration

Exocytosis: Movement of material out of the cell

Endocytosis: Movement of material in to the cell

Phagocytosis: When a cell engulf a solid mass (eating)

Pinocytosis: When a cell engulfs liquid mass (drinking)

Diffusion:

 Transport of solute from higher to lower concentration

Facilitated diffusion:

 It requires protein carrier in form of energy in ATP across the cell membrane

Simple diffusion:

 Transports from higher concentration to lower concentration without energy input

Osmosis:

 Is diffusion of water across a selectively permeable membrane that allows free passage of water but no more than one solute

 Plasmolysis: contraction of cytoplasm of a plant cell as a result of osmosis out of the cell

Note: Permeable: Allows fluids to flow in

Solute: Which has to be dissolved

Solvent: Already dissolved

Hyper tonic:  concentration of solute than cell, water diffused out and cell shrinks/contracts

Hypotonic:  concentration of solute than cell causing water to diffuse into the cell, expands, burst

Isotonic:  concentration of solute as the cell, so water diffuse evenly equilibrium

Exocytosis: Movement of material out of the cell

Endocytosis: movement of materials in to the cell

Phagocytosis: Is when a cell engulfs a solid mass (eating)

Pinocytosis: Is when a cell engulfs liquid mass (drinking)

How does diffusion work:

 molecules dissolved in a solution due to kinetic energy

 Higher to lower concentration is diffusion

 Diffusion is one of the processes whereby materials are exchanged between a cell and environment

How osmosis works:

 Water molecules across a membrane from an area of high water concentration to an area lower concentration

 Non polar molecules will pass through membrane

Classification

Biodiversity: all thing things

Taxonomy: Naming living things

 Living things are recognized by their feature and can be classified (or divided