Chapter 6 Holt Science and Technology Life Science GENES AND DNA
goes over vocab and basic information
Terms in this set (34)
deoxyribonucleic acid, a molecule that is present in all living cells and that contains the information that determines the traits that a living thing inherits and needs to live
in a nucleic-acid chain, a subunit that consist of a sugar, a phosphate, and a nitrogenous base
ribonucleic acid, a molecule that is present in all living cells and that plays a role in protein production
a cell organelle composed of RNA and protein; the site of protein synthesis
a change in the nucleotide-base sequence of a gene or DNA molecule
The difference between DNA and RNA
1.DNA is found in the nucleus, RNA is is found in the nucleus and the cytoplasm.
2.DNA is a twisted ladder (double strands) RNA is a single strand.
3.DNA contains the base Thymine RNA contains the base Uracil instead.
4.DNA contains deoxyribose (sugar) RNA contains Ribose (another type of sugar.
The 4 bases of DNA
guanine, cytosine, thymine, adenine (guanine and cytosine are always equal, thymine and adenine are always equal)
Copying of DNA
Occurs during Interphase, and this process occurs by...
1.) An enzyme breaks the bonds between the nitrogen bases.
2.) The bases attached to each strand pair up with a new supply of bases found in the cytoplasm.
3.) Sugar and Phosphate groups form the side (handrail) of each new DNA strand.
When DNA copies are made
DNA is copied every time a cell divides. The job of unwinding, copying and re-winding the DNA is done by proteins within the cell
pair of cromatin that are exactly alike
is the material in the cell that contains DNA and carries genetic information
an organic compound that is made of one or more chains of amino acids and that is a principal component of all cells
The base that pairs Adenine in DNA (NOT FOUND IN RNA)
The base that pairs with Thymine in DNA
The base that pairs with Cytosine in DNA
The base that pairs with Guanine with DNA
consists of a string of nucleotides that give the cell info about how to make a specific trait
Structure of DNA
DNA is like a ladder or spiral staircase. The outside is made of a sugar-phosphate backbone with alternating sugars and phosphates and the inside "steps" are the nitrogenous bases.
RNA molecule that carries copies of instructions for the assembly of amino acids into proteins from DNA to the rest of the cell
The first step is to copy the side of DNA containing a gene. A copy of the DNA segment is made of RNA. This RNA is called messenger RNA (mRNA). mRNA moves out of the nucleus of the cell and into the cytoplasm. Once in the cytoplasm is put in a protein "assembly line" which is run by a ribosome. RNA is fed through the ribosome 3 bases at a time. Then transfer RNA (tRNA) translate the RNA message each tRNA molecule picks ups a specific amino acid from the cytoplasm. Inside the ribosome bases of tRNA match up with bases from mRNA. the tRNA molecules release their amino acids. These acids turn into a growing chain. As more RNA is fed through the ribosome, the growing chain of amino acids fold into a new protein molecule.
type of RNA molecule that transfers amino acids to ribosomes during protein synthesis
small organelle in the cell on which proteins are assembled; made of RNA and protein
3 types of mutations
insertion, deletion, substitution
A mutation involving the addition of one or more nucleotide pairs to a gene.
1. A deficiency in a chromosome resulting from the loss of a fragment through breakage. 2. A mutational loss of one or more nucleotide pairs from a gene.
a mutation in which a nucleotide or a codon in DNA is replaced with a different nucleotide
How mutations happen
Mutations happen regularly because of random errors when DNA is copied.
process of making changes in the DNA code of living organisms
identifying the unique pattern in each and everyones body; mostly used for evidence in crimes
any agent (physical or environmental) that can induce a genetic mutation or can increase the rate of mutation
building blocks of proteins
Sickle cell disease
A human genetic disease caused by a recessive allele that results in the substitution of a single amino acid in the hemoglobin protein; characterized by deformed red blood cells that can lead to numerous symptoms.
Characteristics that are inherited
A three-nucleotide sequence of DNA or mRNA that specifies a particular amino acid or termination signal; the basic unit of the genetic code.