click below
click below
Normal Size Small Size show me how
Science Ch 4 Vocab
Question | Answer |
---|---|
cell membrane | the semipermeable membrane surrounding the cytoplasm of a cell |
cell wall | a rigid layer of polysaccharides lying outside the plasma membrane of the cells of plants, fungi, and bacteria. |
chloroplasts | a plastid that contains chlorophyll and in which photosynthesis takes place. |
chromatin | the material of which the chromosomes of organisms other than bacteria (i.e., eukaryotes) are composed. |
chromosome | a threadlike structure of nucleic acids and protein found in the nucleus of most living cells, carrying genetic information in the form of genes. |
cytoplasm | the material or protoplasm within a living cell, excluding the nucleus. |
deoxyribonucleic acid | a biological molecule found in the cell nucleus that carries genetic information. |
endoplasmic reticulum | a network of membrane-covered chemicals within a cell that transports materials |
enzymes | a substance produced by a living organism that acts as a catalyst to bring about a specific biochemical reaction. |
gene | a unit of heredity that is transferred from a parent to offspring and is held to determine some characteristic of the offspring |
gene mutation | a change in the specific order of the A, G, C, and T bases that make up a particular gene. |
gene therapy | techniques developed to alter mutated genes in order to make them function normally. |
Golgi Body | a complex of vesicles and folded membranes within the cytoplasm of most eukaryotic cells, involved in secretion and intracellular transport. |
hormones | a regulatory substance produced in an organism and transported in tissue fluids such as blood or sap to stimulate specific cells or tissues into action. |
mitochondria | an organelle found in large numbers in most cells, in which the biochemical processes of respiration and energy production occur. |
mutagens | substances or factors that can cause mutation in DNA. |
negative mutation | a mutation that harms a an organism or reduces the probability that organisms with the mutation can produce offspring or survive in their environment. |
neutral mutation | a mutation that does not affect the organism or does not increase or decrease the survival rate of the organism |
nuclear membrane | the thin outer membrane that surrounds the cell nucleus |
nuclear pores | openings in the nuclear membrane that allow only certain materials into and out of the nucleus. |
nucleolus | a small dense spherical structure in the nucleus of a cell during interphase. |
nucleus | the central and most important part of an object, movement, or group, forming the basis for its activity and growth |
organelle | any of a number of organized or specialized structures within a living cell. |
positive mutation | a mutation that benefits an organism |
proteins | any of a class of nitrogenous organic compounds that consist of large molecules composed of one or more long chains of amino acids and are an essential part of all living organisms |
ribosome | a minute particle consisting of RNA and associated proteins, found in large numbers in the cytoplasm of living cells. |
vacuoles | a space or vesicle within the cytoplasm of a cell, enclosed by a membrane and typically containing fluid. |
vesicles | membrane covered sacs that form off the ends of endoplasmic reticulum and the Golgi body an that transport proteins, nutrients, and water into, out of and around the inside of a cell |