Science Terms TAKS Objective 2

Process by which molecules move from an area of high concentration to an area of low concentration def: Diffusion

The movement of water across the plasma membrane from an area of high concentration to an area of low concentration. def: Osmosis

State of being balanced, example maintaining body temperature or water balance in an organism. def: Homeostasis

Ability to let things pass through, this is the cell membranes function. def: Permeability

Protects and lines cell lets things pass in and out of the cell def: Cell membrane

Chlorophyll containing organelle found in green plants and some protests def: Chloroplasts

Membranes forming a type of transport system def: Endoplasmic reticulum

Eukaryotic organelle in which food molecules are broken down to produce energy def: Mitochondrion

Organelle involved in protein synthesis def: Ribosome

Gene form for each variation of a trait of an organism def: Allele

Molecule coding organism’s information code, consists of a sugar, phosphate and a nitrogen base def: DNA

Single Stranded molecule that forms a copy of DNA for use in protein synthesis def: RNA

A part of cell division in which the nucleus divides, the end result is 2 identical daughter cells that are identical to the parent cell def: Mitosis

Process by which the number of chromosomes per cell is cut in half, used by organisms to produce gametes def: Meiosis

Error or change in the DNA sequence Change in nitrogen bases def: Mutation

Way to find expected proportions of genotypes of offspring of a cross def: Punnet Square

Branch of biology dealing with grouping an naming organisms def: Taxonomy

Broadest level of classification def: Kingdom

Multi-cellular consumers that eat other organisms for food def: Animals

Group of prokaryotes that produce their food in unusual ways. Usually live in extreme environments def: Archaebacteria

Prokaryotes living under normal conditions def: Eubacteria

Heterotrophic eukaryotic consumers that absorb nutrients from decomposing wastes and dead organisms def: Fungi

Stationary multicellular eukarotes that photosynthesize def: Plants

Single celled eukaryotes def: Protists

Single celled organisms lacking membrane bound organelles def: Prokaryotes

Organism composed of cells with organelles. May be unicellular or multicellular def: Eukaryotes

Includes heart, blood vessels and blood, transports nutrients and wastes within the body def: Circulatory system

Receives and breaks down food and absorbs nutrients def: Digestive system

Controls metabolic activities of the body def: Endocrine system

Filters the blood, collects and excretes wastes def: Excretory system

Protects the body from infections def: Immune system

Skin and its associated structures def: Integumentary system

Provides for movement of the body def: Muscular system

Supports body def: Skeletal system

Provides sensory function def: Nervous system

Involved in the production of gametes def: Reproductive system

Provides area for gas exchange in the organism def: Respiratory system

A group of cells working together def: Tissue

A group of tissues working together def: Organ

A group of organs working together to maintain homeostasis def: Organ system