Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

NURS 1650 - Here We Go Again > Genetics > Flashcards

Genetics Flashcards

1
Q

Histones

A

Proteins that DNA wrap around

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Chromatin

A

Repeating units of nucleosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Characteristics of euchromatin

A

Relaxed, loosely packed, genes are highly expressed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Characteristics of heterochromatin

A

Tightly packed together, genes are poorly expressed

Harder for enzymes to move past the tightly packed genes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

During cell division, chromatin tightly condenses into _____

A

Chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is a centromere?

A

The constriction point of a chromosomes that divides it into two sections

The location of the centromere gives the chromosome its characteristic shape and can be used to help describe the location of specific genes

Short arm –> p arm

Long arm –> q arm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is a promoter? - Basic Structure of a Gene

A

Base-pair sequence that specifies where transcription begins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is RNA coding sequence? - Basic Structure of a Gene

A

Base-pair sequence that includes coding information for the polypeptide chain (protein - although not yet in final form) specified by the gene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is terminator? - Basic Structure of a Gene

A

Sequence that specifies the end of the mRNA transcript

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What direction does nucleic acid synthesis occur in?

A

Synthesized in a 5’ to 3’ direction

DNA and RNA polymerases can only add nucleotides to the 3’ carbon on the previously incorporated base

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What enzyme is responsible for the process of DNA replication?

A

DNA polymerase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Do all replication errors become mutations?

A

NO

Only when they are not corrected

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the “end problem” in DNA replication?

A

The newly synthesized lagging strand has a gap of about 100 bases

This gap can start to eat into the chromosome, causing it to get shorter and shorter –> eventually lose functionality

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are telomeres? What do they do?

A

Complex of noncoding DNA & binding proteins at ends of linear chromosomes

Act like a cap on chromosomes

Maintain its structural integrity –> “solve” the end problem

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What does a telomerase enzyme do? What kind of cells is it present in?

A

It maintains telomeric length by adding more tandem repeats to chromosomes

Present only germ cells, stem cells, and cancer cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is transcription?

A

Process of making an RNA copy of a gene sequence

In preparation for synthesizing the protein that gene codes for

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

3 Steps of Transcription

A

Initiation

Elongation

Termination

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What does RNA polymerase do?

A

Initiates synthesis

lacks proofreading capabilities

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is an exon?

A

expressed sequence, translated protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is an intron?

A

intervening sequence removed during splicing, not found in mature mRNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is translation

A

Process by which mRNA is used to direct synthesis of a specific protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

tRNA Structure and Function

A

Carries amino acid to ribosome to lengthen the growing peptide chain

Recognition between mRNA codon and tRNA anticodon with complementary base pairing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the ribosomes job in translation?

A

Find starting place on mRNA

Line up tRNA on mRNA

Set correct reading frame for codon triplets

Catalyze peptide bonds that hold together amino acids

Releases newly synthesized protein chain when a stop codon is reached

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are Post-Translational Modifications? Why are they important?

A

Modifications of the polypeptide product of translation, after the translation process, is complete

NOT encoded in DNA, but are essential for the proper functioning of the protein

Increase protein functionality and diversity, regulate activity, localization, and interaction of proteins with other cellular molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Central Dogma
DNA *transcription* RNA *translation* Polypeptide Folding or Post-Translational Modification FINAL PROTEIN
26
What is a wild-type allele?
The allele that encodes the phenotype most common in a particular population The "normal" allele
27
What is a mutant allele?
Any form of an allele other than the wild type
28
What is penetrance?
A measure of proportion of individuals in a population who carry a disease-causing allele AND express the disease population
29
What is complete penentrance?
ALL people with the allele display the disease phenotype
30
What is incomplete penetrance?
SOME people with the allele do not display the disease phenotype
31
What is expressivity?
The degree to which a genotype is expressed phenotypically in individuals
32
Not every mouse expresses purple tail pigment in their phenotype, despite having the requisite allele in their genotype. What is this an example of?
Incomplete penetrance
33
Every mouse expresses purple tail pigment in their phenotype, but some tails are dark purple and some are light; pigment intensity varies What is this an example of?
Variable expressivity
34
Some mice have dark purple tails, some have light purple tails, and some have tails with no purple pigment What is this an example of?
Both incomplete penetrance and variable expressivity
35
Familial Adenomatous Polyposis (FAP) -- if you inherit the disease-causing allele, you will get colon cancer, usually at an early age What is this an example of?
Complete penetrance
36
Hereditary Non-Polyposis Colorectal Cancer (HNPCC) -- if you inherit the disease-causing allele, there is an 80% chance that you will get colon cancer, and can cause cancer in other organ systems What is this an example of?
Incomplete penetrance with variable expresivity
37
In people who have the allele coding for the mutation that causes achondroplasia, 100% of them will display the phenotype. This is known as _____
Complete penetrance
38
In people who have the allele coding for a mutation that causes osteogenesis imperfect, some will have mild disease and some will have severe disease. These differences in disease severity are also known as __________
Variable expressivity
39
What are the two common types of mutation at the single gene level?
Frameshift mutation Point mutation
40
What is a frameshift mutation?
The addition or removal of one or more bases changes the "reading frame" Alters the primary structure of a protein Deletion, insertion
41
What is a point mutation?
Single base (and thus, base pair) substation May cause affected codon to signify an abnormal amino acid
42
What are the three subtypes of point mutations?
Missense --> wrong amino acid is made (ex. sickle cell anemia) Nonsense --> a premature codon is inserted Silent Mutation --> same amino acid is made (bc redundancy)
43
Germ cell vs Somatic cell Mutations
Germline Mutation: - Originates in germ cells - Entire organism carries the mutation - Half of the gametes carry the mutation Somatic Mutation: - Originates in body cells - Affects a patch of area - None of the gametes carry the mutation
44
What is a monogenic disease?
One gene is mutated and is responsible for the disease example: Sickle-cell Anemia (HBBgene) Classification --> location: autosomal or sex chromosomes
45
What are polygenic and multifactorial diseases?
More than one gene is mutated Environmental factors may also play a role example: T2DM
46
Autosomal Dominant Diseases
Due to a mutation of a specific autosomal gene 1 mutant allele sufficient for disease phenotype to be expressed
47
Autosomal Recessive Diseases
2 mutant alleles needed for the disease phenotype to be expressed Unaffected may transmit to offspring
48
Sex-Linked (X-linked) Disease
Mutation of sex chromosome (X) Almost all are recessive Males ALWAYS express // females when XX
49
If G6PD were deficient in RBC, why would that be especially problematic? What is it about RBCs, in particular?
RBC have no nucleus When undergoing large amounts of hemolysis, they cannot synthesize more
50
What are Single-Nucleotide Polymorphisms (SNPs)?
DNA sequence variations where a single nucleotide is altered
51
What are Genome-wide Association Studies (GWAS)?
seek to identify distribution of SNPs, across diff population, and associations of SNPs, rearrangements and copy number variants with various diseases Can be used to predict an individual's risk of developing a disorder
52
When is/can a gene be expressed?
A gene is expressed when the protein for which it codes is created/synthesized
53
What is gene regulation?
The process of turning genes on and off
54
What is the role of miRNAs in gene expression?
Regulate proteins produced, prevent protein from being made
55
What is epigenetics?
Modifications in gene expression without alteration of genetic structure does NOT involve mutation, NO change in DNA sequence
56
What is DNA methylation?
Most common modification in epigenetics addition of methyl groups low DNA methylation --> high level of expression high DNA methylation --> low level of expression
57
Polymerase Chain Reaction (PCR)
Takes short fragments (10,000 - 40,000 base pairs) and amplifies them to be studied
58
Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)
Used for gene knockout, repression, or editing of a stretch of DNA within a gene
59
DNA replication is:
Both continuous and discontinuous
60
You would expect to find telomerase enzyme in which of the following cell types?
Liver cancer cells Stem Cells Sperm
61
Which type of point mutation would result in a protein that is too short?
Nonsense
62
Sickle Cell Disease is an autosomal _____________ disease and requires _________ copies of the mutated allele for the phenotype to be expressed
Sickle Cell Disease is an autosomal RECESSIVE disease and requires TWO copies of the mutated allele for the phenotype to be expressed
63
In people who have the allele coding for a mutation that causes Marfan Syndrome, an autosomal dominant disease, some people have mild symptoms, such as being tall and thin with long, slender fingers. Others also have life-threatening dysfunction involving the cardiovascular system. These differences in disease severity are also known as ___________
Variable expressivity
64
T/F Offspring with XY chromosomes always express the disease if they inherit the mutated gene on the X chromosome X-linked/Sex-linked Diseases
True
65
T/F All the offspring with XX chromosomes born to a father who has the disease will also have the disease. X-linked/Sex-linked Diseases
False We do not know the genetic status of the mother
66
T/F Offspring with XX chromosomes always express the disease if they inherit 1 copy of the mutated gene on the X chromosome. X-linked/Sex-linked Diseases
False Offspring with XX chromosomes would have to inherit 2 copies of the X chromosome with the mutated allele in order to express the disease. If they inherit 1 X chromosome with the mutation, their other X chromosome (without the mutation) can function normally
67
T/F Offspring with XY chromosomes, born to an affected father and a mother with no mutated gene on an X chromosome, will never inherit the disease. X-linked/Sex-linked Diseases
True
68
What is the clinical significance of familial hypercholesterolemia?
Atherosclerotic plaques would be expected to form in an affected person's coronary arteries An affected person will have very high blood levels of LDL cholesterol Adolescents who are affected may have coronary artery calcification
69
What is true of micro RNAs (miRNA)?
They provide a feedback system when a gene is expressed.
70
CRISPR is a technique that can be used to:
Edit a gene Silence a gene
71
Missense Mutation Result
Wrong amino acid is made ex. sickle cell anemia
72
Nonsense Mutation Result
Premature stop codon inserted Shorter protein
73
Silent Mutation Result
Same amino acid is made Bc redundancy
74
Autosomal Dominant Example: Familial Hypercholesterolemia (FH) --> autosomal dominant or recessive?
Autosomal dominant
75
Patho of Familial Hypercholesterolemia (FH)
The gene that is mutated in Familial Hypercholesterolemia codes for a receptor in the liver that removes LDL cholesterol from the blood Now cannot remove LDL-C from the bloodstream Reduced clearance of LDL-C from circulation --> high levels of plasma LDL-C from birth Increased atherosclerotic plaque formation w/ subsequent calcification
76
Sickle Cell Disease is autosomal ____
recessive
77
SCD Patho
the specific mutation found in sickle cell disease is a missense causes a single amino acid substitution causes the sickling shape Results in ischemia, jaundice, anemia, destruction of the spleen, increased infections,
78
G6PD Deficiency is a _____ disease
X-linked recessive disease
79
G6PD Deficiency S/Sx
Jaundice, fatigue, tachycardia 2/2 acute hemolytic anemia
80
Which disease appears to be protective against progression to severe malaria in about 2/3 of males?
G6PD Deficiency

NURS 1650 - Here We Go Again (20 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions