TEST STUDY GUIDE BIO TEST DNA AND RNA

What is the name of the sugar found in the nucleotides of DNA?

Deoxyribose

What does DNA stand for?

Deoxyribonucleic Acid

Are cytosine and thymine purines?

False

What type of structure do purines have?

Two rings

What is the backbone of the DNA molecule made of?

Sugar and phosphate molecules

Frederick Griffith conducted experiments on which type of bacteria?

Pneumonia-causing bacteria

What did Griffith call the process where harmless bacteria were transformed into harmful bacteria?

transformation

What type of biological molecule did Oswald Avery determine was responsible for transformation?

DNA

What did Hershey and Chase use to determine that DNA was the genetic material?

Radioactive sulfur and phosphorus

What significant rule did Erwin Chargaff discovered regarding the bases in DNA?

A alway equals T and G always equals C

Who was primarily responsible for producing the first image of DNA’s structure?

Rosalind Franklin

DNA structure adenine and thymine are connected by how many hydrogen bonds?

Two

Which model of DNA did Watson and Crick introduce in 1953?

A double-stranded helix

Which of the following is true?

RNA is usually single-stranded

Which type of RNA brings the information in the genetic code from the nucleus to other parts of the cell?

mRNA

Which molecules are involved in protein synthesis?

messenger RNA, ribosomal RNA, and transfer RNA

During eukaryotic transcription, an RNA molecule is formed that is

Complementary to part of one strand of DNA

How many RNA nucleotides are needed to specify four amino acids?

12

During translation, the type of amino acid that is added to he growing polypeptide depends on the

codon on the mRNA and the anticodon on the tRNA

RNA polymerase ______ a ______ to initiate transcription.

does not, primer

Amino acids are linked by __________ during translation

Peptide bonds

What signals the end of protein synthesis?

stop codon

Each _____ on mRNA corresponds to one ______.

codon, amino acid

What is the start codon for mRNA?

AUG/ methionine

When does mRNA translation occur?

the cytoplasm with ribosomes

What do you call the process described in these two chapters?

gene expression

The anticodon is a part of the _____ molecule.

mRNA

Hydrogen bond counts for nitrogenous bases:

2:AT/TA

3:GC/CG

Gene

The specific order of nitrogen bases located on a specific region of a chromosome (20,000 to 25,000)

The order of nitrogenous base pairs is a code for

A specific form of a gene

What does the gene do?

it instructs cells to synthesize certain proteins

What do proteins give organisms?

expressed physical traits

What happens before a cell divides

it duplicates its DNA in a process called replication

What does replication do?

It ensures that each cell that divides will have a complete set of DNA.

What do Watson and Crick’s models suggest?

DNA serves as a template during replication.

Describe DNA replication

DNA synthesis always proceeds in a

5 to 3 direction vice versa

Where do you add nucleotides?

Helicase

enzyme that separates double-stranded DNA into single strands allowing each strand to be copied

DNA polymerase

the enzyme that joins individual nucleotides to produce a new strand of DNA.

How is replication in Prokaryotic cells?

replication starts from a single point and then proceeds in two direction until the whole chromosome is copied

How many chromosomes do humans usually have

23 pairs 46 total

Mutation

heritable change in genetic information

Gene mutation

changes in a single gene

Point mutation

occur at a single point in the DNA sequence, generally during replication

Guess and define

-Point mutation

What genetic mutation has the most adverse effect?

Insertions and deletions

Guess and define

Chromosomal Mutation:

produce changes in the number or structure of chromosomes. Can change the location of genes on chromosomes and can even change the number of copies of some genes

Deletion

Duplication

Inversion

Translocation

What are the two causes of mutation?

-errors in replication

-mutagens

Mutagens

chemical or physical agents in the environment

-pesticides, alkaloids, tobacco smoke, env. pollutants

-radiation like x-rays and UV light

What do cells do about mutation?

cells can sometimes repair the damage; but when they cannot, the DNA base sequence changes permanently

What are mutations the source of in a species?

genetic variability

What are three effects of mutations?

-no effect

-beneficial variations

-negative disruption of gene function

What is the most common disease from chromosome mutations?

Down syndrome

DNA contains the instructions to

make proteins

RNA controls

the assembly of amino acids into proteins

DNA to RNA process is known as

transcription

RNA to protein process is known as

translation

What is the central dogma

DNA→RNA→Protein

What is RNA

-a nucleic acid that consists of a long chain of nucleotides (Ribonucleic acid)

What are the three main differences between DNA and RNA

-the sugar in RNA is ribose

-RNA is single stranded

-nucleotides (monomers) (thymine v Uracil)

Which one is more liable?

RNA

mRNA

Carries copy of instructions for assembling amino acids into proteins

Transcription

Process where segments of DNA serve as templates to produce complementary RNA molecules (occurs in the nucleus)

RNA polymerase

-enzyme that separates the DNA strands and uses one strand of DNA as a template from which to assemble nucleotides into a complementary strand of RNA

-transcription

Promoter

sequence of DNA that shows RNA polymerase where to begin making RNA

Terminator

sequence of DNA that cause transcription to stop

Picture describing transcription for description (try to recite)

RNA Editing

includes introns and exons that transform Pre-mRNA into mRNA

Introns

portions that are cut out and discarded of pre-mRNA

Exons

Remaining pieces of RNA that are spliced back together to form the final mRNA

(Think of the gas station Exxon keeping only the best gas)

Translation

-The process of decoding of an mRNA message into a protein

-occurs in the cytoplasm (specifically ribosomes)

How are proteins made?

proteins are made by joining amino acid monomers together into long chains called polypeptides

How many amino acids does it take to create a protein?

20 minimum

What does the amino acid sequence mean?

the sequence influences the shape and function of the protein

Codon

consists of three consecutive RNA bases that specify a single amino acid to be added to the polypeptide chain

Ribosomal RNA forms

subunits of ribosomes

Transfer RNA (tRNA)

transfers each amino acid to the ribosome as it is specified by the coded messages in mRNA

Peptide bond

Make this DNA strand a matching RNA strand: TAG CAT TTT ACA

AUC GUA AAA UGU

What is ribosomal RNA’s function

reading mRNA strands to be translated into a polypeptide chain

Large Subunit (LSU)

Catalyzes peptide bond formation

Small Subunit (SSU)

Binds to mRNA and endures correct codon-anticodon pairing

tRNA Binding Sites

The location where tRNA goes in the ribosomal RNA to lay down its anti codon (connects to codon) and amino acid

What turns another bacteria from non disease causing to disease causing

-another bacteria transferring chemical factor/ DNA

-process called transformation

-permanent

Experiment 1 vs 2

-1 used enzymes to destroy proteins, lipids, carbohydrates, and RNA from heat killed bacteria (transformation)

-2 used enzymes to destroy DNA (no transformation)

What does DNA do?

Store, transmit, and copy genetic information (genes) in a cell.

Virus

nonliving particles that can infect living cells