Exam #3 from slideshow Flashcards
(103 cards)
1
Q
What are prokaryotes?
A
genomes small and circular
2
Q
Where is the DNA in prokaryotes?
A
DNA in cytoplasm
3
Q
What are eukaryote?
A
genome larger and linear
4
Q
Where is DNA in eukaryotes
Located?
A
DNA is in the nucleus
5
Q
what is the first step to Binary fission
A
- Circular bacterial DNA molecule attached by protien to inner surface of membrane
6
Q
What is Binary fission
A
Prokaryotic cell division
7
Q
Second step to binary fission
A
- DNA replication begins ; moves bi-directionally around the circular DNA
8
Q
Third step to binary fission
A
- Newly synthesized DNA molecule also attaches to the inner membrane ; near attachment site to the parent molecule
9
Q
fourth step to binary fission
A
The cell gets longer ; separating DNA molecules
10
Q
fifth step to binary fission
A
Synthesis of new cell membrane ; cell division starts
11
Q
sixth step to binary fusion
A
Parent and daughter cell seperate ; Synthesis completes
12
Q
What are the two types of Eukaryotic cell division?
A
Mitosis and Meiosis
13
Q
Primary function of Mitosis
A
asexual reproduction of somatic cells
14
Q
Why Mitosis?
A
Tissues can grow and repair (cells male re move cells)
So organisms can reproduce a sexually
15
Q
Primary function of meiosis
A
production of gametes
16
Q
Whats a gametes
A
sperm and eggs
17
Q
Why Meiosis?
A
So organisms can produce Sexually
18
Q
Where does Mitosis take place?
A
All somatic cells
19
Q
Where does Meiosis take place
A
specialized germ cells in gonads
20
Q
What is the primary difference between prokaryotic and eukaryotic genomes?
A
Prokaryotic genomes are small and circular, while eukaryotic genomes are large and linear
Prokaryotic DNA is located in the cytoplasm, whereas eukaryotic DNA is found in the nucleus.
21
Q
What is the process of prokaryotic cell division called?
A
Binary fission
In binary fission, DNA replication begins at a specific location and proceeds bi-directionally.
22
Q
What are the two types of eukaryotic cell division?
A
- Mitosis
- Meiosis
Mitosis is for asexual reproduction of somatic cells, while meiosis is for the production of gametes.
23
Q
What are the stages of interphase in the eukaryotic somatic cell cycle?
A
- G1: Pre-synthesis growth
- S: Synthesis of DNA via replication
- G2: Post-synthesis growth
Interphase is the phase before cell division.
24
Q
What are homologous chromosomes?
A
Chromosomes that carry the same genes but may have different versions (alleles) of those genes
They have similar sizes and shapes.
25
What occurs during prophase of mitosis?
Chromosomes condense, and centrosomes produce microtubules that migrate to opposite poles
## Footnote
The mitotic spindle is composed of microtubules.
26
What is the outcome of mitosis?
Two identical daughter cells are produced
## Footnote
There is no reduction in chromosome number.
27
What is crossing over and when does it occur?
The exchange of genetic material between non-sister chromatids during prophase I of meiosis
## Footnote
This results in recombinant chromatids.
28
What are the main differences between meiosis and mitosis?
* Meiosis results in four haploid gametes
* Mitosis results in two diploid daughter cells
* Meiosis includes two rounds of division
## Footnote
Meiosis reduces chromosome number, while mitosis maintains it.
29
What are the phases of the cell cycle?
* G1 phase
* S phase
* G2 phase
* M phase
## Footnote
M phase includes both mitosis and cytokinesis.
30
What is the function of cyclin proteins in the cell cycle?
Cyclin proteins bind to and activate cyclin-dependent kinases (CDK) to control progression through the cell cycle
## Footnote
Cyclin-CDK complexes phosphorylate target proteins that promote cell division.
31
What is the role of the p53 protein in the cell cycle?
p53 inhibits the cell cycle when DNA damage is detected, allowing time for repair
## Footnote
It acts as a transcription factor to turn on genes that produce proteins inhibiting cell division.
32
True or False: Tumor suppressor genes promote cell division.
False
## Footnote
Tumor suppressor genes encode proteins that inhibit cell division.
33
What is the multiple mutation model for cancer development?
* Activation of oncogene
* Inactivation of tumor suppressor genes
* Development from normal cells to benign cancer to malignant cancer
## Footnote
Metastasis can occur when malignant cancer spreads to new sites.
34
Fill in the blank: The process of _______ produces haploid gametes.
Meiosis
## Footnote
This process is essential for sexual reproduction.
35
What is a genome?
All the genetic material in an organism
36
Which type of genomes are the smallest?
Viral genomes
37
How is genome size measured?
Number of nucleotides or base pairs (bp)
38
What is the size of the COVID-19 genome?
30,000 bp
39
What does MB stand for in genomic terms?
Megabase = 1 million base pairs
40
What is lateral gene transfer (LGT)?
Movement of genetic material between organisms other than by vertical transmission
41
What is the C value paradox?
The amount of DNA in a cell is not strongly related to the complexity of an organism
42
What are the three fundamental components of genomic research?
* Genome Sequencing
* Genome Assembly
* Genome Annotation
43
What is genomics?
An interdisciplinary field of biology focused on the structure, function, evolution, mapping, & editing of genomes
44
What is the Sanger method?
A chain termination method for DNA sequencing, commercialized in 1987
45
What is Next Generation Sequencing (NGS)?
A sequencing technology available since 2004 that allows high-throughput whole-genome sequencing
46
What is the primary purpose of Polymerase Chain Reaction (PCR)?
To amplify/replicate DNA
47
What are the steps involved in PCR?
* DNA sample
* dNTP (nucleotides)
* Primers
* Taq Polymerase
* Buffer solution
48
What is structural annotation in genome annotation?
Identification of genomic elements and their locations within the genome
49
What are noncoding DNA sequences?
Sequences that do not code for proteins but may have regulatory functions
50
What is a mutation?
Any change in the genetic material of an organism
51
What is the difference between somatic cells and germ cells regarding mutations?
Somatic mutations are not heritable; germ cell mutations are passed on to offspring
52
What is a single-nucleotide polymorphism (SNP)?
A substitution of a single nucleotide at a specific position in the genome present in a large fraction of the population
53
What is the role of short tandem repeat (STR) polymorphisms in DNA fingerprinting?
They provide a unique combination of alleles based on the number of repeats at each STR site
54
What is copy number variation (CNV)?
Variation in the number of copies of a particular region of the genome
55
True or False: Mutations are random and unrelated to their usefulness to the organism.
True
56
What can cause cystic fibrosis at the genetic level?
Nucleotide deletion mutations
57
What is a frameshift mutation?
A mutation caused by nucleotide insertion or deletion that alters the reading frame of the gene
58
What are the types of point mutations?
* Synonymous (silent) mutations
* Nonsynonymous (missense) mutations
* Nonsense mutations
59
What technique is commonly used to separate DNA fragments by size?
Gel Electrophoresis
60
What is the average size of a human protein-coding gene?
10,000-15,000 base pairs of DNA
61
What is the typical mutation rate in smaller genomes?
Higher mutation rates per cell cycle
62
What percentage of the human genome is due to copy number variation (CNV)?
5-10%
63
Fill in the blank: The process of identifying all organisms in an environmental sample is known as _______.
Metagenomics
64
What is the role of genomic annotation?
Attaching biological information to genomic elements
65
What is genetic variation?
Genetic differences that exist among individuals in a population at a particular point in time
## Footnote
This concept is essential in understanding how traits are inherited and expressed.
66
Define genotype.
The genetic makeup of a cell or organism
## Footnote
The genotype determines the potential traits that can be expressed.
67
What is a gene?
Segment of DNA that codes for a protein
## Footnote
Genes are the basic units of heredity.
68
What are alleles?
Alternate versions of a gene
## Footnote
Alleles can be dominant or recessive.
69
Define locus.
Location of a gene
## Footnote
The locus is crucial for identifying gene positions on chromosomes.
70
What is a phenotype?
An individual’s observable characteristics (e.g., height, eye color)
## Footnote
The phenotype is the physical expression of a genotype.
71
What is Mendel's Principle of Segregation?
During gamete formation, alleles for a trait segregate from each other
## Footnote
This principle explains how offspring inherit one allele from each parent.
72
What is a dihybrid cross?
Predicts inheritance patterns of two genes that are independent of each other
## Footnote
Dihybrid crosses help in understanding the concept of independent assortment.
73
What does Mendel’s Principle of Independent Assortment state?
Genes are inherited independently of other genes
## Footnote
This principle applies when genes are located on different chromosomes.
74
True or False: Genetic linkage means that genes on the same chromosome exhibit independent assortment.
False
## Footnote
Linked genes do not assort independently due to their proximity on the chromosome.
75
What is incomplete dominance?
Heterozygous genotype displays a unique phenotype that differs from that of homozygous genotypes
## Footnote
An example is the blending of flower colors.
76
What is codominance?
Heterozygous genotypes simultaneously display multiple phenotypes
## Footnote
An example is AB blood type.
77
What is pleiotropy?
One gene influences two or more seemingly unrelated phenotypic traits
## Footnote
This concept highlights the complexity of gene functions.
78
What is a polygenic trait?
Multiple genes contributing to one phenotype
## Footnote
These traits often show a range of phenotypes, such as height.
79
Fill in the blank: Almost none of the genes in the ______ chromosome have counterparts in the Y chromosome.
X
## Footnote
This difference in gene content impacts sex-linked traits.
80
What is the expected ratio of XX (female) and XY (male) progeny from random fertilization?
1/2 XX and 1/2 XY
## Footnote
This ratio results from the segregation of sex chromosomes during meiosis.
81
What are X-linked traits?
Traits whose genes are located on the X chromosome
## Footnote
Males are more likely to express recessive X-linked traits like colorblindness.
82
What is genetic linkage?
Genes on the same chromosome exhibit linkage and are called linked genes
## Footnote
The closer genes are on a chromosome, the more likely they are to be inherited together.
83
What does the frequency of gene recombination indicate?
It is used to determine the distance between genes and map their relative locations on a chromosome
## Footnote
Recombination frequency is a key concept in genetic mapping.
84
What is heritability?
The proportion of variation in a trait that can be attributed to genetic differences
## Footnote
Heritability is often studied using twin studies.
85
Define concordance in the context of twin studies.
Percentage of cases in which both members of a pair of twins show the trait
## Footnote
High concordance rates indicate a strong genetic influence on traits.
86
What is regression toward the mean?
The tendency for offspring to resemble the average of their parents rather than the extremes
## Footnote
This concept illustrates the influence of both genetics and environment.
87
What is a complex trait?
A trait influenced by multiple genes and environmental factors
## Footnote
Examples include height, weight, and susceptibility to diseases.
88
True or False: Mitochondrial DNA is inherited directly via the maternal lineage with no recombination.
True
## Footnote
This mode of inheritance is crucial for tracing maternal ancestry.
89
G 1
Pre. synthesis growth
90
S
Synthesis of DNA via reproduction ; Interphase
91
G2
Post synthesis growth ; Interphase
92
Humans have ___ # of chromosomes
23 pairs; total n=46
93
Prophase (Mitosis)
Chromosomes condenses ; Centrosomes make microtubes + move to polar ends
94
Pro metaphase (Mitosis )
Microtubes of Microspindles attach to chromosomes
95
Metaphase (Mitosis)
Chromosomes aline in center of the cell
96
Anaphase (Mitosis)
sister chromatides pulled apart to poles by Microspindles
97
Telophase (Mitosis)
theformation of nuclear envelope ; Chromosomes condense.
98
Prophase I ( Meiosis)
Neclear membrane breaks down ; homologous chromosomes condence
...
non sister chromatinds attach (Bivalent) switch DNA
99
Prometaphase I (Meiosis)
Microtubes attach to Kinetochores on chromosomes
100
Metaphase I ( Meiosis )
Pairs line up on equator
101
Anaphase I (Meiosis)
Homologous Chromosomes seperate ; sister chromatinds stay together
102
Telophase I (Meiosis)
Two cells form (. cytokinesis)
103
Meiosis second phase
prophase, Metaphase, Anaphase, telophase
Anaphase - chromosomes pulled apart = cromatids
