DNA/PS STUDY GUIDE

DNA and PS study guide, this DOES NOT include all of the information

what is a nucleotide?

the building block of DNA

parts of a nucleotide?

-sugar

-phosphate

-nitrogenous base

the 4 nitrogenous bases?

-adenine

-thymine

-guanine

-cytosine

the purines?

adenine and guanine

the pyrimidines?

cytosine and thymine

where is the hydrogen bond?

where the two bases connect

What is the backbone structure?

the sugar-phosphate part of DNA

What’s a double helix?

the shape of DNA that resembles a spiraled, twisted ladder

What does antiparallel mean?

parallel but in opposite directions

What’s a mutation?

a change in the DNA sequence of an organism

What are mutagens

any known agent that can cause mutation

What is it called when mutation causes cancer?

a carcinogen

Frameshift Mutation?

every amino acid that follows will be altered

Silent Mutation?

letter change, gives the same needed amino acid

Missense Mutation

letter change, gives a different amino acid that is not needed for that codon

Nonsense Mutation

letter change, gives a STOP codon

Deletion Mutation?

chromosomal mutations where a segment of a chromosome is LOST

Insertion Mutation?

chromosomal mutation where a segment of a chromosome is ADDED

Translocation?

chromosomal mutations where a segment from one chromosome is TRANSFERRED to another

Duplication

chromosomal mutation where a segment is transferred to its HOMOLOGOUS chromosome

Inversion

chromosomal mutation where a segment of a chromosome arm is INVERTED

3 Mutagen Agents

1. Physical Agents

2. Chemical Agents

3. Biological Agents

Semiconservative?

half-saving

Three Types of RNA?

1. TRNA

2. MRNA

3. RRNA

Job of Helicase?

unzips DNA by breaking the hydrogen bonds connecting the two strands of DNA

Job of Primase?

makes RNA primer to indicate where to start building the new strand of DNA

Job of DNA Polymerase?

builds the new strand of DNA

Job of Ligase?

glues all the fragments on the lagging strand together

Where does DNA replication occur?

nucleus

When does DNA replication occur?

during the S phase of interphase

Where does translation occur?

ribosome (cytoplasm)

What is being made during translation?

amino acids

What is a codon?

triplets mRNA is read in

tRNA?

-reads codons and builds amino acids

-brings amino acids to ribosome

rRNA?

-follows code to make proteins using amino acids

-core of the ribosome

Three steps of translation?

1. initiations

2. elongation

3. termination

What is transcription?

the process of making a copy of DNA in the form of mRNA

Where does transcription occur?

nucleus

What makes mRNA?

RNA Polymerase

What is RNA Polymerase?

an enzyme that binds to DNA and bonds free floating RNA nucleobases to the DNA strand

-unwinds and unzips

Who is Erwin Chargaff

an Austrian chemist born in 1947 that concluded that A=T and C=G through his experiments

germ cell mutation

a mutation that impacts at least one gamete

somatic mutation

mutations that impacts one cell or section of cells withing the organism

What does DNA stand for?

Deoxyribonucleic Acid