DNA, RNA, and Protein Synthesis

80 pts. - 15 mc, 5 fill in the blank, 7 sa (19 pts), 16 labeling, 22 wheel

Griffith (1928)

isolated 2 strands of bacteria; performed trials on a rat and found the harmless rough bacteria turned into deadly smooth bacteria... this was the transforming factor which was a gene

Avery (1944)

Showed that DNA is made up of genes

Hershey and Chase (1952)

tested to prove that DNA, not protein is the genetic material

Franklin (1952)

studied x-ray pictures of DNA and its structure; took photo 51

Watson and Crick (1953)

produced the first model of DNA which showed it was a double helix

Chargaff

The individual responsible for discovering the base pairing rules for DNA.

When did the Human Genome Project begin and end?

1990-2003

What does DNA stand for and where is it found in the cell?

Deoxyribonucleic acid

In the nucleus

What are histones, nucleosomes, chromatin and chromosomes?

Histones- protein that DNA wraps around

Nucleosomes- groups of DNA around nucleosomes

Chromatin- uncoiled up DNA

Chromosomes- packed DNA

What are the 3 parts of a nucleotide?

phosphate group, sugar, nitrogen base

What are the bases of DNA and how are they different?

Adenine- bigger; 2x ring; PURINE

Guanine- bigger; 2x ring; PURINE

Cytosine- smaller; 1x ring; PYRIMIDINE

Thymine- smaller; 1x ring; PYRIMIDINE

What types of bonds hold DNA bases together and how many between the base pairs?

Hydrogen bonds

2 bonds between A and T

3 bonds between G and C

What makes up the sides of DNA helix?

phosphate and deoxyribose(sugar)

What are the roles of DNA?

stores info, copies info, and gene expression

What are telomeres and what does telomerases do?

Telomeres- tips of chromosomes

Telomerase- adds extra sections of DNA to prevent tips from damage

How are RNA and DNA different?

RNA: leaves the nucleus, single strands, ribose, uracil

DNA: only in nucleus, double strands, deoxyribose, thymine

What enzymes are involved in DNA replication?

Helicase- unzips the helix

Ligase- joins the fragments together + seals it together

DNA Polymerase- helps attach and makes sure everything is in the right order

When does DNA need to replicate? Why does it need to?

During the S phase. It divides so that there is enough DNA for cell division for the new cells to have the right amount of DNA.

What is the difference between the leading and lagging strands of DNA?

Leading- nucleotides attach easily

Lagging- nucleotides are put together in fragments and then ligase puts the fragments together

What is the end result of DNA replication?

2 identical strands of DNA

What enzymes are involved in transcription?

RNA polymerase

What is the end result of transcription?

single strand of RNA

What is the function of mRNA? Where is it found in the cell?

carries the instructions from sections of DNA. Found in the nucleus and cytoplasm.

What is a codon?

group of 3 bases

What are the start and stop codons?

Start: AUG

Stop: UGA, UAG, UAA

What do you use to read the wheel?

mRNA

What is the function of tRNA? Where is it found?

In the cytoplasm.

It transfers the amino acids to the ribosome

What is an anticodon?

An anticodon is the three unpaired bases on a tRNA that is complementary to a codon on mRNA.

What is the function of rRNA? Where is it found?

cytoplasm + nucleus

Provides binding site for mRNA and tRNA

What is the end result of translation?

protein

Where does replication, transcription, and translation occur?

Replication- nucleus

Transcription- Nucleus

Translation- cytoplasm

What type of bonds hold the amino acids together?

peptide bonds

Know the different types of mutations and what can do wrong.

Gene:

Substitution- one base is switched

Insertion- too many bases (order gets messed up)

Deletion- one base is deleted (order gets messed up)

Chromosomal:

Deletion- loss of part or all of a chromosome

Duplication- extra copy of all or part of a chromosome

Inversion- reverses directions of parts of the chromosome

Translocation- part of one chromosome breaks off and attaches to another

Point Mutation

1 nucleotide

Frameshift mutation

inserts and deletions; changes sequences and proteins.