Alternate versions of a gene that produce variation in inherited traits
Alleles
One gene affects multiple traits, such as sickle cell affecting oxygen transport and malaria resistance
Pleiotropy
Bases A (adenine) and G (guanine) are called
Purines
The enzyme that separates DNA strands during replication?
Helicase
Enzyme responsible for reading the DNA template and building an RNA strand
RNA polymerase
The protective structure is added to the 5' end of mRNA to prevent degradation.
5'cap
A single nucleotide change in DNA is called.
Single nucleotide polymorphism
If you cross two true-breeding parents with different alleles for a trait, what will the genotype of all F1 offspring be?
Heterozygous
Why don't females show double expression for X-linked traits even thought they have two X chromosomes?
one X chromosome per cell becomes inactivated
Bases C (cytosine) and T (Thymine) are called
Pyrimidines
Enzyme that prevents DNA supercoiling during replication
Topoisomerase
DNA sequence where RNA polymerase attached to begin transcription
Promoter
These non-coding regions are removed from RNA before translation, while exons remain to code for proteins.
Introns
A mutation that changes one nucleotide but still codes for the same amino acid.
When an organism has two identical alleles for a trait, what is its genotype called?
Homozygous
A dominant allele that is rare in the population, like polydactyly, shows that dominance does not equal
High allele frequency
Bonds that hold complementary DNA bases together are
Primase
In eukaryotic cells, where does transcription occur and why?
In the nucleus, because DNA cannot leave the nucleus
This ribosomal site is where a charged tRNA first pairs with the codon on mRNA
A site
A mutation that changes one amino acid to another, such as in sickle cell disease.
Missense mutation
Law stating that two copies of a gene separate during gamete formation
Law of segregation
Because of this genetic phenomenon, when a deadly event strikes, some individuals are wiped out while others survive and reproduce, passing on their traits.
Genetic variation
Number of hydrogen bonds between C-G
Three
Protein that binds single-stranded DNA to prevent other molecules from binding
Single-stranded binding proteins
The type of RNA is created by transcription and carries genetic information to the ribosome.
mRNA
After its amino acid is added to the growing chain, the tRNA sits here.
P site
A mutation that changes an amino acid codon into a stop codon.
Nonsense mutation
A cross between red and white flowers produces pink offspring. What is this called?
Incomplete dominance
What kind of inheritance produces a close range of phenotypes? An example of this inheritance is skin color.
Polygenic inheritance
Number of hydrogen bonds between A-T
Two
Enzyme that adds nucleotides to the growing DNA strand
DNA polymerase
Ribosome
Once a tRNA has delivered its amino acid, it moves into this ribosomal site before leaving.
E site
Mutations that create new varieties in populations, such as different ladybug patters, are examples of what evolutionary process.
Variation
What is it called when both alleles are fully expressed in the phenotype, like black and white checkered chickens.
Codominance
Heterozygous individuals for this condition have malaria resistance
Sickle cell disease
DNA shape discovered by Watson and Crick
Double helix
Short DNA fragments on the lagging strand
Okazaki fragments
Three phases of transcription
2. Elongation
3. Termination
The feet of tRNA that match up with codons on mRNA are called this.
Mutation that improves traits like lactose tolerance or tetrachromatic vision.
Beneficial mutations
What is it called when one gene is masking another?
Epistasis
Why are some dominant alleles, like dimples or Huntington's disease, rare in the population?
Because they do not significantly help with survival or reproduction
What ensures that the diameter of DNA stays consistent along the helix?
Purine paired with pyrimidine
Three phases of DNA replication
1. Initiation
2. Elongation
3. Termination
Difference in transcription between prokaryotes and eukaryotes
Prokaryotes: transcription and translation occur simultaneously
Eukaryotes: transcription happens in nucleus, translation happens in cytoplasm
This molecule serves as the link between mRNA codons and the amino acids that form a polypeptide.
tRNA
This process acts on mutations, driving the survival and reproduction of organisms best suited to their environment.
Natural selection