Wednesday, 27 February 2013

Biology Vocabulary Words

Biology Vocabulary Words
A large complex molecule made up of one or more chains of amino acids. Proteins perform a wide variety of activities in the cell.
Nitrogen Base:
Component of a nucleotide that can bind to other nitrogen bases through a hydrogen bond
A unit of DNA or RNA, consisting of one chemical base plus a phosphate molecule and a sugar molecule.                                       
Amino Acid
The basic building block of a protein. There are 20 different amino acids commonly found in proteins. The genetic code specifies the sequence of amino acids in a protein.
Cellular organelle that is the site of protein synthesis in the cytoplasm
A sequence of three nucleotides on a strand of m-RNA that codes for an amino acid.
A 3-base sequence in a tRNA molecule that base-pairs with its complementary codon in an mRNA molecule.
The process of copying information from DNA into new strands of messenger RNA (mRNA), which then carries the information to the cytoplasm
The process of turning instructions from mRNA, codon by codon, into chains of amino acids that then fold into proteins.
A chemical cousin of DNA. RNA (ribonucleic acid) is responsible for translating the genetic code of DNA into proteins.
Messenger RNA  or “mRNA”
Messenger RNA arises in the process of transcription from the DNA in the nucleus and determines the amino acid sequence during the translation process of protein synthesis
Transfer RNA (tRNA)
Transfer RNA has a three-nucleotide sequence (the anticodon) that is complementary to a three-nucleotide sequence in mRNA (the codon). Attachment of an amino acid places the amino acid in proximity to allow the formation of peptide after interacting with mRNA and the Ribosome.
A unit of DNA that determines and transmits hereditary characteristics from parent to offspring.
The process of producing sperm, the male reproductive cells.
The process of egg formation.

The offspring from sexual reproduction.
Protein Synthesis
The process in which the genetic code carried by messenger RNA directs cellular organelles called ribosomes to produce proteins from amino acids
The handing down of certain traits from parents to their offspring. The process of heredity occurs through the genes.
A gene that almost always results in a specific characteristic, even when the person’s genome only contains one copy
Refers to a characteristic that is apparent only when two copies of the gene encoding it are present--one from the mother and one from the father.
Having two identical forms (alleles) of a particular gene (eg AA, aa).
Possessing two different forms (alleles) of a specific gene (eg., Aa or Bb)
a single set of chromosomes (half of the full set of genetic material). In humans, the haploid number of chromosomes is 23.
A full set of genetic material, consisting of paired chromosomes - one chromosome from each parental set. Most animal cells except the gametes have a diploid set of chromosomes. The diploid human genome has 46 chromosomes.
A sex cell.  A sperm cell in males, an egg in females.
A person who carries the potential for a disease that may be passed on to others.
The state of being heterozygous where two forms of the same gene are present (eg., Aa, Bb)
A family tree diagram that shows how a particular genetic trait or disease has been inherited through many generations of a family
Inheritance of a gene carried on a sex chromosome
The observable traits or characteristics of an organism, for example hair color, weight, or the presence or absence of a disease.
The genetic characteristics of a cell or organism. Often used to refer to  the combination of the alleles on a particular chromosome.
One of two or more alternative forms of a gene; for example, one allele of the gene for eye color codes for blue eyes, while another allele codes for brown eyes.
The cell resulting from the fusion of the male and female (haploid) gametes; the fertilised ovum.
Incomplete Dominance:
A situation where neither gene dominates the other and both exercise an influence on the individual.  In this situation, a red flower crossed with a white one might result in a pink flower.

The situation in which two different alleles for a trait are expressed unblended in the phenotype of heterozygous individuals, in other words, both traits are expressed in some ways.