Structure and Function of DNA
DNA Replication
RNA and Transcription
Protein Synthesis
Mutations
100
One DNA strand has a base sequence GTCCATA. The base sequence on the second strand of DNA is...
CAGGTAT
100
What does the word "replicate" mean? During what phase of the cell cycle does DNA replication take place?
S-phase
100
A single stranded piece of a DNA has the following bases: ACTGAG. What is the matching sequence on its RNA transcript?
UGACUC
100
This process turns mRNA into a protein.
Translation.
100

What is a mutation? Name 2 environmental factors can cause a mutation.  What are the two major categories of mutations?

Any change to an organism's DNA/genome. Environmental factors: chemicals, radiation, sun, food, & viruses

Two categories are 1) gene mutations & 2) chromosomal mutations

200
What do we call the monomers of DNA? What are its 3 parts? Which two parts form the backbone? What is the function of the backbone?
Nucleotide: phosphate group, sugar (deoxyribose), base (A, C, T, or G). The phosphate and sugar form the backbone. The backbone provides structure and support for the molecule.
200
What is the end product of DNA replication (be very specific!)
Two new molecules of DNA, each is identical to each other and to the original molecule.
200
Transcription: What does is make? What enzyme makes the product? Where does it take place?
RNA. RNA polymerase. Nucleus.
200
What cell organelle makes protein? What are the monomers of protein called?
Ribosome / amino acids
200
What is a frameshift mutation?
This type of mutation occurs when bases are inserted or deletedm, causing ALL the codons from the point of mutation forward to change, thus change causing all the amino acids to change.
300
Describe the function/purpose of DNA in organisms. What is a gene?
A gene is a sequence of DNA nucleotides that acts as a recipe for a specific protein.
300
Name the two enzymes involved in DNA replication and describe their function.
Helicase: unzips/unwinds the DNA helix by breaking the bonds between the bases. DNA polymerase: makes DNA by adding complementary bases to the other side of each of the original strands.
300
Why can’t DNA leave the nucleus?
DNA is too long/bulky to exit through the nuclear pores.
300
What is an anti-codon? What is its purpose?
A 3 nucleotide sequence on a tRNA that matches to a specific mRNA codon. When a tRNA finds a matching mRNA codon (with the ribosomes help), it drops off the attached amino acid to be used in protein.
300
Are all mutations harmful? If not, give a counter example.
Helpful mutations: having ONE sickle cell gene makes you immune to the parasite that causes malaria. Neutral mutations: blue eyes
400
These two men are credited with figuring out the shape & structure of DNA. They used a photograph taken by a female fellow scientist (+points if you can name the female scientist).
James Watson and Francis Crick (+points for Rosalind Franklin)
400
Why does DNA need to be copied?
So that when the cell divides, each new cell has a complete set of DNA.
400
Name the three different types of RNA and describe the function of each of them.
mRNA: delivers a copy version of a DNA gene from the nucleus to the ribosome. tRNA: transfers the amino acids to the ribosome. rRNA: part of the ribosome.
400
A ribosome makes a protein containing 60 amino acids. The corresponding mRNA consists of at least how many codons?
60
400

There are two (2) categories of point mutations.  What are they?  Which is worse and why?

1) substitutions

2) insertions (additions) & deletions

#2 is worse because  they cause a shift in the reading frame (codons) on the rest of the polynucleotide (frameshift mutation).

500
In a sample of DNA, 40% of the bases are adenine. What percentage of bases are guanine?
10%
500
Why is DNA replication called a "semi-conservative" process?
DNA replication is "semi-conservative" because each new molecule of DNA has one original strand and one newly synthesized strand (it is half conserved, or half saved)
500
Name 4 differences between DNA and RNA.
DNA: deoxyribose, thymine, long, double-stranded, made by DNA replication. RNA: ribose, uracil, short, single-stranded, made by transcription.
500
1) The bonds that the ribosomes use to hold amino acids together during protein synthesis are called… 2) This is what we call a chain of amino acids (a protein before it gets its shape)
Peptide bonds. Polypeptide.
500
What is a chromosomal mutation? Give an example.
Alterations to a piece of a chromosome or a whole chromosome [e.g., Down syndrome (3 chromosome #21)]
600

The parent strand being replicated is copied starting at its _____________ end toward its ____________ end.

3' toward its 5'

600

A tRNA carrying an amino acid first enters the ___________ site at the ribosome?

A site

700

Okazaki Fragmemts are formed on which strand?

The lagging strand

700

The tRNA that is holding the polypeptide chain is found in the ____________ site?

P site

800

What joins the Okazaki fragments?

DNA ligase

800
What is the start codon?   Which amino acid does it bring?

AUG - It brings the amino acid methionine.

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