AI generated through (pdf) Flashcards
1
Q
What are proteins composed of?
A
Polymers of amino acids
2
Q
What is the primary function of enzymatic proteins?
A
Act as catalysts for biochemical reactions
3
Q
What role do transport proteins play in the body?
A
Facilitate the transport of nutrients and molecules
4
Q
What is the function of defensive proteins?
A
Include antibodies that recognize and eliminate pathogens
5
Q
What do receptor proteins do?
A
Help transmit signals to cells, coordinating activities
6
Q
What is the primary role of structural proteins?
A
Provide support and strength
7
Q
Where are contractile proteins primarily found?
A
In muscle cells
8
Q
What is the function of storage proteins?
A
Store and supply amino acids to developing embryos
9
Q
What is the significance of protein structure?
A
Crucial for their function
10
Q
What are globular proteins?
A
Proteins with a compact, spherical shape
11
Q
What are fibrous proteins?
A
Elongated and fibrous structural proteins
12
Q
What is denaturation?
A
The alteration of a protein’s shape, rendering it nonfunctional
13
Q
What are the three components of amino acids?
A
- Amino group (-NH₂) * Carboxyl group (-COOH) * Variable R group
14
Q
How many different amino acids are there?
A
20 different amino acids
15
Q
What are essential amino acids?
A
Amino acids that must be obtained through diet
16
Q
What type of bond links amino acids together?
A
Peptide bonds
17
Q
What is primary structure in proteins?
A
The unique sequence of amino acids in a polypeptide chain
18
Q
What is secondary structure in proteins?
A
Formed by hydrogen bonds between atoms in the polypeptide backbone
19
Q
What are the two main types of secondary structure?
A
- Alpha Helix (α-helix) * Beta Pleated Sheet (β-sheet)
20
Q
What stabilizes tertiary structure in proteins?
A
- Hydrophobic interactions * Hydrogen bonds * Ionic bonds * Disulfide bridges
21
Q
What characterizes quaternary structure in proteins?
A
Proteins composed of multiple polypeptide subunits
22
Q
What is the role of DNA?
A
Carries the instructions for assembling polypeptides
23
Q
What are nucleotides made up of?
A
- Five carbon sugars * Phosphate group * Nitrogenous base
24
Q
What is the difference between RNA and DNA?
A
RNA is single-stranded; DNA is double-stranded
25
What is protein synthesis?
The process of converting genetic information into proteins
26
What are the two sub-processes of protein synthesis?
* Transcription * Translation
27
What is a codon?
A three-base 'word' that codes for an amino acid
28
What is the start codon?
Methionine (Met)
29
What occurs during transcription?
Genetic information from DNA is converted into RNA
30
What enzyme is responsible for transcription?
RNA polymerase
31
What are the three steps of transcription?
* Initiation * Elongation * Termination
32
What is RNA splicing?
The process of removing introns and joining exons in RNA
33
What is the role of tRNA in translation?
Interprets codons to deliver corresponding amino acids
34
What are the three phases of translation?
* Initiation * Elongation * Termination
35
What is a silent mutation?
Nucleotide substitution with no effect on the amino acid
36
What is a missense mutation?
Nucleotide substitution that alters the amino acid
37
What is a nonsense mutation?
Change of a codon to a stop codon
38
What is a frameshift mutation?
Disruption caused by insertion or deletion of nucleotides
39
What is the cell cycle?
The series of events that take place in a cell leading to its division
40
What are the phases of interphase?
* G1 phase * S phase * G2 phase
41
What happens during mitosis?
The nucleus and contents divide
42
What are the five main phases of mitosis?
* Prophase * Prometaphase * Metaphase * Anaphase * Telophase
43
What is cytokinesis?
The division of the cytoplasm into two daughter cells
44
What is anchorage dependence?
Requirement for cells to be attached to a surface to divide
45
What is density-dependent inhibition?
Cells stop dividing when they touch neighboring cells
46
What are benign tumors?
Localized tumors that do not spread
47
What are malignant tumors?
Tumors that can metastasize and spread
48
What are common treatments for cancer?
* Surgery * Radiation * Chemotherapy
49
What prevents cell growth in normal conditions?
Division and their absence prevents cell growth.
50
How do cancer cells behave in terms of division?
Cancer cells do not follow normal controls and keep dividing even when crowded.
51
What is the difference between benign and malignant tumors?
Benign tumors stay localized, while malignant tumors spread (metastasis).
52
What are the three treatment options for cancer?
* Surgery
* Radiation
* Chemotherapy
53
Why is cancer treatment personalized?
Cancer affects people in different ways, making it hard to find a one-size-fits-all solution.
54
What are somatic cells and how many chromosomes do they contain?
Somatic cells are typical body cells that contain 46 chromosomes.
55
What are homologous chromosomes?
Homologous chromosomes are matching pairs that have genes for the same characteristics.
56
What are gametes, and how many sets of chromosomes do they contain?
Gametes are haploid cells that contain a single set of chromosomes.
57
What is the product of fertilization called?
Zygote.
58
What happens during Meiosis I?
Homologous cells become haploid chromosomes but have doubled chromosomes.
59
What are the phases of Meiosis I?
* Prophase I
* Metaphase I
* Anaphase I
* Telophase I
* Cytokinesis
60
What occurs during crossing over?
Homologous chromosomes exchange segments in a process during Prophase I.
61
What is independent assortment?
Independent assortment happens during metaphase I when homologous chromosome pairs line up randomly.
62
What is the formula for the total number of possible chromosome combinations in gametes?
2^n, where n is the haploid number.
63
What are the two types of chromosomes?
* Autosomes
* Sex chromosomes
64
What is a karyotype?
A photographic inventory of an individual’s chromosomes.
65
What causes Down syndrome?
An extra copy of chromosome 21, resulting in trisomy 21.
66
What are some symptoms of Down syndrome?
* Round face
* Skin fold near eyes
* Irregular teeth
* Short body
* Heart defects
67
What is nondisjunction?
A process when a gamete receives two of the same type of chromosome.
68
What are the four types of structural changes that can occur in chromosomes?
* Deletion
* Duplication
* Inversion
* Translocation
69
What is the primary cause of cancer development?
Mutations in genes that control cell division lead to uncontrolled growth.
70
What are oncogenes?
Genes that can cause cancer by stimulating excessive cell division.
71
What role do signal transduction pathways play in cell division?
They regulate cell division through stimulatory and inhibitory signals.
72
What are carcinogens?
Substances like UV radiation and tobacco that contribute to cancer.
73
What is gene expression?
The process of turning genes on or off in response to environmental changes.
74
What is the role of the lac operon in E. coli?
It regulates the expression of genes needed to metabolize lactose.
75
Fill in the blank: Crossing over occurs during ______.
Prophase I
76
True or False: All errors in cell division are harmful.
False.
77
What can lead to the development of new species?
Errors in cell division can lead to the evolution of new species.
78
What happens during Meiosis II?
It is similar to mitosis and results in four daughter cells, each with the haploid number of chromosomes.
79
What is a recombinant chromosome?
Chromosomes that contain genes from both maternal and paternal chromosomes in new combinations.
80
What genetic change leads to chronic myelogenous leukemia (CML)?
A reciprocal translocation between chromosomes 9 and 22.
81
What are the two control sequences that help control gene expression?
Promoter and operator
## Footnote
The promoter initiates transcription, while the operator determines if RNA polymerase can attach.
82
What is an operon?
A cluster of functionally related genes controlled by a shared operator
## Footnote
Example: lac operon.
83
What role does the repressor play in transcription regulation?
Blocks the attachment of RNA polymerase to the promoter
## Footnote
The repressor is coded by a regulatory gene and is expressed continually.
84
How can the lac operon be turned on?
Lactose binds to the repressor, changing its shape
## Footnote
This prevents the repressor from binding to the operator.
85
What type of operon is the lac operon?
Inducible operon
## Footnote
It is usually off but can be induced by lactose.
86
What type of operon is the trp operon?
Repressive operon
## Footnote
It is usually on but can be repressed by the presence of tryptophan.
87
What are activators in the context of operons?
Proteins that turn on gene transcription by binding to DNA
## Footnote
They help RNA polymerase bind to the promoter.
88
What is the primary regulation point for eukaryotic gene expression?
Initiation of transcription
## Footnote
Eukaryotic gene expression is regulated at multiple levels.
89
What do activators bind to in eukaryotic gene regulation?
Enhancers
## Footnote
Enhancers are often far from the gene they regulate.
90
What is alternative RNA splicing?
The same RNA transcript can be spliced in different ways
## Footnote
This produces multiple mRNA molecules from a single gene.
91
What is the significance of alternative splicing in humans?
Increases protein diversity
## Footnote
Over 90 percent of protein-coding genes undergo alternative splicing.
92
What happens to eukaryotic mRNA after transcription?
It undergoes processing to become mature mRNA
## Footnote
This includes adding a cap and tail, and splicing coding exons.
93
What are the four ways gene expression can be regulated after mRNA processing?
mRNA breakdown, initiation of translation, processing of protein, protein breakdown
## Footnote
Each of these steps can control gene expression.
94
What are homeotic genes?
Master control genes that regulate groups of other genes
## Footnote
They determine the body's anatomy.
95
What is the role of gene cascades in development?
One set of genes activates another in a chain reaction
## Footnote
This ensures proper development of body segments.
96
What is nucleic acid hybridization used for?
To detect the presence of specific mRNAs in cells
## Footnote
It involves a complementary probe labeled with a fluorescent tag.
97
What is a DNA microarray?
A tool to study thousands of genes at once
## Footnote
It helps determine which genes are active in various conditions.
98
What do red spots indicate on a microarray?
Genes active in one sample
## Footnote
Green spots indicate genes active in another sample, yellow spots in both, and black spots in neither.
99
How can microarrays be applied in cancer research?
They help classify different types of cancer based on gene expression patterns
## Footnote
This aids in personalized treatments.
100
What are the three key steps in signal transduction pathways?
Reception, transduction, response
## Footnote
These steps allow cells to communicate and respond to external signals.
101
What is the significance of cell signaling in yeast?
It increases genetic variation through mating types
## Footnote
This process involves the fusion of two different genetic lineages.
