Science

• Axon


  the part of the neuron that transmits impulses away from the cell body
• Dendrite


  the branchlike structure of the neuron that extends from the cell body to receive an impulse
• Embryo


  an organism in its early stages of development, especially before it has reached a distinctively recognizable form
• Endocrine Gland


  an organ that produces chemical secretions released directly into the bloodstream
• Egg Cell


  also called ovum (plural: ova); the female gamete
• Fertilization


  a process that occurs when the sperm and egg combine to produce an embryo
• Homeostasis


  the ability or tendency of an organism to maintain internal equilibrium by regulating its processes
• Hormone


  a chemical substance produced in the body that controls and regulates the activity of certain cells or organs
• Impulse


  an electrochemical gradient moving along a neuron
• Neuron


  the basic unit of the nervous system, also called nerve cell, that transmits messages to and from the central nervous system
• Semen


  the ejaculated fluid containing sperm cells andsecretions from the seminal vesicle, prostate gland, and bulbourethral gland
• Sperm


  shorter term for spermatozoon (plural: spermatozoa); the male gamete
• Stimulus


  any factor in the environment that influences the behavior of an organism
• Synapse


  the space between neurons where electrochemical signals pass
• Amino acid


  the building blocks of a protein molecule
• Anticodon


  the complement of the mRNA; triplet code in the tRNA
• Chromosomal mutations


  changes in the chromosomes where parts of the chromosomes are broken and lost during mitosis.
• Codon


  each set of three nitrogenous bases in mRNA representing an amino acid or a start/stop signal
• DNA replication


  process in which the DNA is copied
• Genetic code


  set of rules that specify the codons in DNA or RNA that corresponds to the amino acids in proteins
• mRNA(messenger RNA)


  a type of RNA that brings information from the DNA in the nucleus to the cytoplasm
• Mutation


  any change in the DNA sequence.
• Nitrogenous base


  is a carbon ring structure that contains one or more atoms of nitrogen. In DNA, there are four possible nitrogen bases: adenine(A), thymine(T), cytosine (C) and guanine(G)
• Recombinant DNA


  a form of DNA produced by combining genetic material from two or more different sources by means of genetic engineering.
• rRNA(ribosomal RNA)


  a type of RNA that hold tightly to the mRNA and use its information to assemble amino acids
• Transcription


  process of copying DNA sequence into RNA.
• Translation


  process of converting information in mRNA into a sequence of amino acids in a protein.
• tRNA(transfer RNA)


  a type of RNA that attach the correct amino acid to the protein chain that is being synthesized in the ribosome.
• Adaptation


  the ability of an organism to adjust and thrive in a given environment.
• Analogous structures


  structures in different organisms that are similar in function but different in origin
• Convergent evolution


  an increase in similarities among species derived from different ancestors as a result of similar adaptation to similar environment
• Divergent evolution


  an increase in the difference among descendants of a single ancestral species as time passes
• Evolution


  species change over time
• Fitness


  ability to survive and produce offsprings
• Fossils


  remains of once living things, remains include bones, shells, teeth and also feces
• Gene


  a segment of DNA or RNA that codes for protein or RNA, a molecular unit of hereditary trait
• Homologous structures


  parts of different organisms that are similar in structure but serve different functions
• Reproduction


  the process by which an organism produces offspring and thus perpetuate the species
• Variation


  differences in traits of organisms in a population
• Biodiversity


  the variety of life forms in a particular ecosystem