Final Questions: Genetics
What is thought to be the origin of mitochondria and chloroplasts?
- bacteria that took up residence within a eukaryotic cell - mitochondria: gram negative non-sulfer bacteria - chloroplasts: cyanobacterium
How does DNA differ from RNA
-RNA is single stranded - Contains ribose instead of deoxyribose - Uracil instead of thymine
To make one complete twist (360 degrees) of a DNA double helix, how many base pairs are required?
10
Unique sequences make up approximately what percent of the human genome?
2%
What RNA modification is important for mRNA stability?
3' polyA tailing
One strand of DNA is 5′ - TCCGGAAT - 3′. What is the opposite strand?
3'-AGGCCTTA-5'
What are the observable characteristics of an organism?
3:1, 1:2:1
How many types of histone proteins exist?
4
Describe the directionality of a DNA molecule.
5' to 3'
Who discovered the first observational evidence that genes may be inherited together rather than by simple Mendelian inheritance
Bateson and Punnett
Who discovered the interaction of two genes could produce a phenotype?
Bateson and Punnett
How do researchers interrupt the process of conjugation?
Blender
Where can Inversion loops can occur?
Both paracentric inversions and pericentric inversions
What did the scientists Nirenberg and Matthaei study?
Cell -free translation system
Where are genes physically located?
Chromosomes
This form of DNA transfer uses a sex pilus to transfer the genetic material?
Conjugation
What set of scientist provided visual proof that chromosomes exchange pieces of information during crossing over. Explain
Creighton and McClintock
What Nucleotides are found in DNA? RNA?
DNA: ATGC RNA: AUGC
When a nucleotide is attached to a DNA strand, the cleavage of the dNTP into deoxyribonucleoside monophosphate and pyrophosphate is what type of reaction?
Exergonic
Activator proteins bind to silencer sequences and repressor proteins bind to enhancer sequences. T or F
F
A genetic linkage map indicates the precise distance between two genes of interest. True or false
False
A repressor protein would enhance the ability of TFIID to bind to the TATA box of the promoter. T or F
False
Mendel's work on inheritance had an immediate influence on the scientific community and theories of inheritance. True or false
False
Which virus uses reverse transcriptase in its reproductive cycle?
HIV
What are areas of the chromosome that are highly condensed and transcriptionally inactive
Heterochromatin
Explain gene interaction
If a combination of two or more genes is required to produce a specific trait
Where are the ribosomal subunits assembled?
In the nucleolus
What are the functions of both MARs and SARs?
MARs & SARs: DNA sequences interspeed in the genome.
In a Z-W system, which is considered to be the homogametic sex?
Male
At what phase do chromosomes line up in the center of the cell?
Metaphase
When mapping genetic distance what unit of measurement is used?
Minute
What are the four levels of study a geneticist would evaluate? (*hint population, etc.)
Molecular level, cellular level, organism level, population level
What are individuals within a population that possess drastically different external markings, but are the same species?
Morphs
Do Both parents usually imprint the same gene. Explain
No, it is usually the mother due to maternal effect
Where is the bacterial chromosome located?
Nucleoid
Visible or measurable characteristics of an organism are called?
Phenotype
At what phase does the nuclear membrane starts to disassociate?
Prophase
In transcription, the closed complex consists of?
RNA polymerase: Transcription factors double-stranded DNA
What researcher(s) initially used X-ray diffraction to gather information on the DNA molecule
Rosalind Franklin and Maurice Wilkins
What is the genetic material in the parvovirus?
Single standed DNA
The first person to suggest that a connection exists between the function of a gene and the production of an enzyme was Archibald Garrod. T or F
T
What general transcription factor is most often affected by regulatory transcription factors?
TFIID
What general transcription factor is a helicase?
TFIIH
What is found at the end of a eukaryotic chromosome?
Telomeres
Explain incomplete penetrance
The environment may affect the outcome of the trait There may be modifier genes that affect the phenotype, which differ in different individuals
What is natural selection?
The process of differential survival and reproduction based on genes and traits
In transcription, the RNA has a complementary sequence to what strand?
The template strand of DNA
What is the purpose of DNA replication?
To make two daughter cells
The __________ process forms RNA.
Transcription
An Alu sequence is an example of what?
Transposable Elements
Steroid hormones are an example of an effector which regulates regulatory transcription factor activity. T or F
True
List the known stop codons?
UAA, UAG, and UGA
What causes the coat color of calico cat?
X-linked allele
If a gene is located on the X chromosome, but not the Y, it is classified as?
X-linked gene
Is sex determination in humans and Drosophila similar? If so, how?
Yes, X female Y male
What is a testcross?
a phenotypically dominant individual is mated with a recessive individual
What causes gene duplications?
abnormal events during recombination
What are the purine bases?
adenine and guanine
A variation of a gene is called a(n) ________.
alleles
At what phase do sister chromatids separate and move towards opposite poles of the cell?
anaphase
Frederick Griffith discovered what?
bacteria are capable of transferring genetic information through a process known as transformation
The changes in the genetic makeup of a population over time is called? ________.
biological evolution
The C-terminus of a polypeptide always contains
carboxyl group
what statistical tests is used to determine if two genes are linked or assorting independently?
chi-square test
Heteroplasmy is associated with what organelle
chloroplasts
Where is extranuclear DNA located in mammalian cells?
chloroplasts
Studies of X-linked inheritance and sex chromosomes provide the evidence for what theory or principle?
chromosome theory of inheritance
Cytokinesis in animals occurs through the formation of a ________, whereas in plants a ________ forms.
cleavage furrow, cell plate
How do type A and type B blood differ?
code for different sugars
In human blood groups, the fact that an individual can have an AB blood type is an example of.
codominance
What is the backbone of the DNA
consists of the phosphate groups and the deoxyribose sugars
What did the scientists Khorana and colleagues study?
copolymers in a cell-free ove system
What are the pyrimidine bases?
cytosine, thymine, uracil
Explain penetrant percentages
described at the population level
In animals, somatic cells are ________ and gametes are ________.
diploid, haploid
Genomic imprinting is a result of what process
epigenetic regulation
Define gene linkage?
genes on the same chromosome tend to be inherited together
What is the most important result of horizontal gene transfer?
genomic variability and adaptation
In a Punnett square diagram, the outside of the box represents the ________.
haploid gametes
What process does the Holliday model explain?
homologous chromosomes
What is the correct order of meiosis?
interphase, prophase, prometaphase, metaphase, anaphase, telophase, cytokinesis
explain paternal leakage
mitochondria provided through the sperm
Twin spotting provides proof of what genetic event?
mitotic recombination
The processes of transcription and translation are at what level of biological organization.
molecular level
In Incomplete penetrance will individuals who possess that dominant trait always express the trait?
no
Explain maternal effect
only genotype of the mother controls the offspring
The site on a plasmid that is cut, producing a single strand of DNA
origin of transfer
Sickle-cell anemia in humans is an example of?
overdominance
What did the scientist Garrod study?
patients who had defects in their ability to metabolize certain compounds
What are the components of all nucleotides
phosphate group, pentose sugar, nitrogenous base
What is the name of the transcription start site?
promoter
CpG islands are associated with what process?
promoters
Explain sex-influenced inheritance provide an example
soft facial hair in females vs coarse facial hairs in males
RF1 and RF2 are active during what stage?
termination
What do Riboswitches regulate?
transcription, translation, RNA stability, splicing
Regulation of gene expression may occur at which of the following levels?
transcription, translation, and post-translation
What is colchicine used for?
used to promote polyploidy
What features of DNA were suggested by Rosalind Franklin's X-ray diffraction data?
- Helical structure - Too wide for a single-stranded helix - 10 base pairs per turn of the helix
