DNA Structure and Function
Which bases are complementary to each other?
Adenine and Thymine (AT)
Cytosine and Guanine (CG)
What does RNA stand for?
Ribonucleic Acid
What are Alleles and where are Alleles located?
Different versions of the same genes located on Chromosomes.
What are the 3 different types of point mutations?
Insertion, Substitution, Deletion
What is natural selection?
Some organisms in a population have favorable traits and are able to survive and reproduce to pass on their genes
How are the 2 strands held together?
Held together by hydrogen bonds between complementary base pairs.
Name two differences between DNA and RNA.
Any two of the following:
DNA – double helix, RNA – single helix
DNA – base pairs, RNA – nucleobase
DNA – sugar (deoxyribose), RNA sugar (ribose)
DNA – Bases (Adenine, Guanine, Cytosine, Thymine), RNA – Bases (Adenine, Guanine, Cytosine, Uracil)
What is a Genotype and what is a Phenotype?
Genotype: The genetic makeup of an organism (the specific set of genes it carries).
Phenotype: The set of observable characteristics and traits of an organism.
Which types of point mutations also cause frameshift mutations? Why?
Caused by insertion or deletion mutations, changes how the DNA is read
Name 1 Abiotic pressure on natural selection and 1 Biotic pressure on natural selection.
Abiotic: Climate, resource availability, physical conditions, chemical conditions
Biotic: Predators, parasites, competition
Where is DNA located?
In the Nucleus.
Which of the following is the correct sequence to produce a protein?
a. DNA > mRNA > Amino acid > polypeptide > Protein
b. mRNA > DNA > Amino acid > Protein
C. DNA > Amino acid > mRNA > Protein
A
If an offspring is said to be Homozygous dominant, which of the following could be its genotype?
a. rr
b. Tt
c. TT
C
What are the impacts of mutations?
Genetic disorders, Cancer, Evolution
What is a mass extinction event?
A decline in biodiversity
If the sequence of bases in one strand of DNA is CATGAACG, what is the sequence of complementary bases in the other strand of DNA?
GTACTTGC
What two processes are RNA involved in and where does each process take place?
Transcription - Takes place in Nucleus
Translation - Takes place in Cytoplasm
Which one of the following would have a different phenotype from the others?
a. Rr
b. rr
c. rR
b
What are mutagens?
Any physical, chemical, or biological agent/event that increases the rate of mutations
What could happen if there is no genetic diversity with a population?
Poses challenges for survival and adaptability. More vulnerable to biotic and abiotic pressures.
Which parts make up the backbone of DNA?
Sugar (Deoxyribose) and Phosphate
How is DNA replication semiconservative?
Each new DNA molecule has one original strand and one new strand.
In codominance, the heterozygote expresses
a. The recessive trait
b. An intermediate phenotype (mixture of the two parents)
c. Both parents' phenotypes
C
What occurs during an Insertion point mutation?
Extra bases are inserted into a section of DNA.
Name 2 of the 5 principles of natural selection.
1. There is variation within a population
2. Some variations are favorable
3. More offspring are produced than can survive
4. Those that survive and reproduce are those with favorable variations (and will hence pass along these variations to their own offspring)
5. Over enormous spans of time, small changes accumulate, and populations change