Lesson 1 - Introduction Flashcards
(92 cards)
1
Q
basic structural and functional units of life
A
cells
2
Q
“all organisms are composed of one or more cells.”
“the cell is the structural unit of life”
A
- Matthias Schleiden
- Theodor Schwann
(1838-1839)
3
Q
“cells can arise only by division from a preexisting cell”
A
Rudolf Virchow (1855)
4
Q
Living things, though infinitely varied when viewed from the outside, are fundamentally __ inside
A
similar
5
Q
transfer of characters or traits from the parents to their off springs
A
Heredity
6
Q
differences between the characters or traits among the individuals of the same species
A
Variation
7
Q
What do cells carry that define each species
A
hereditary information (DNA)
8
Q
long, unbranched, double-stranded molecule formed by four types of nucleotides
A
DNA
9
Q
forms DNA
A
nucleotides
10
Q
Four types of nucleotides in the DNA
A
- Adenine
- Guanine
- Cytosine
- Thymine
11
Q
charge of the DNA
A
negative
12
Q
forms the nucleotide
A
- phosphate
- sugar
- base
13
Q
link the nucleotides in each strand
A
covalent bonds
14
Q
hold the two DNA strands together
A
hydrogen bonds
15
Q
bond between the phosphate and sugar
A
phosphodiester bond
16
Q
bond between the sugar and base
A
glycosidic bond
17
Q
determines the genetic information
A
sequence of bases
18
Q
two types of bases
A
- purine
- pyrimidine
19
Q
purines
A
Adenine
Guanine
20
Q
pyrimidine
A
Cytosine
Thymine
Uracil
21
Q
hydrogen bonds between adenine and thymine
A
2
22
Q
hydrogen bonds between cytosine and guanine
A
3
23
Q
the first experiment which suggested that bacteria can transfer genetic information through a process called transformation
A
Griffith’s transformation experiment
24
Q
full name of Griffith
A
Frederick Griffith (1928)
25
what type of bacteria did Griffith use
_Diplococcus_ _pneumoniae_ (_Pneumococcus_)
26
Smooth type (S)
- thick polysaccharide capsule
- smooth mucoid colonies
- pathogenic/virulent
27
Rough type (R)
- no capsule
- rough colonies
- non-pathogenic/avirulent
28
Who are the other scientists who had an experiment related to Griffith's transformation experiment
- M.H. Dawson (1930) and
- J.L. Alloway (1932)
29
what did M.H. Dawson (1930) and J.L. Alloway (1932) do
- in vitro transformation
- mouse was not necessary
- extract from heat-killed S cells + live R cells -> live S cells
30
- purified biochemicals (proteins, DNA, RNA) from the heat killed S cells to see which ones could transform live R. cells into S cells
- discovered that DNA alone from S bacteria caused the bacteria to become transformed
Avery, MacLeod, McCarty
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General Properties of Transforming Substance
1. viscous, silky sheen
2. loses activity in distilled water
3. activity retained for months in physiological salt solution
4. withstands heating at 65C for 30-60 minutes
5. loses activity with increased acid concentration
32
showed that phages only injected their DNA into host bacteria, and that the DNA served as the replicating genetic element of phages
Hershey-Chase Experiment
33
what phages were used in the Hershey-Chase Experiment
T2 phages
34
the four scientists who codiscovered the double-helix structure of DNA, which formed the basis for modern biotechnolog
- Francis Crick
- Rosalind Franklin
- James Watson
- Maurice Wilkins
35
"DNA is made of nucleotides"
Phoebus Levene
36
"1 purine : 1 pyrimidine"
- Erwin Chargaff
- Rollin Hotchkiss
- Ronald Fisher
37
suggested that DNA is triple-stranded
Linus Pauling
38
provided X-ray diffraction photograph of crystalline DNA
- Rosalind Franklin
- Maurice Wilkins
39
All cells replicate their DNA by __ __
templated polymerization
40
the nucleotide sequence in one strand is __ to the other strand
complementary
41
- It is the segment of double stranded DNA.
- Runs from 5' to 3'.
- has base sequence same as that of mRNA.
- also known as coding strand.
Sense strand
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- aka template strand.
- runs from 3' to 5'.
- complimentary to sense strand.
- in which transcription occurs.
Antisense strand
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how many origin of replication in prokaryote
1
44
how many origin of replication in eukaryote
multiple
45
DNA fragment corresponding to one protein or RNA
Gene
46
dictates the nature of proteins, when and where they are to be made
genome
47
gene expression is a __ process
regulated
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specify the transcripts and protein products
coding segments
49
serve as punctuations and regulatory sequences that contrl the local rate of transcription
non-coding regions
50
Long non-coding RNA length
~1000 - 10000 nt long with little to no protein-coding potential
51
are RNA molecules larger than 200 nucleotides
Long noncoding RNAs (lncRNAs)
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LncRNA functions
1. transcriptional activation
2. transcriptional repression
3. enchancer RNA
4. scaffolding protein for chromatin remodeling complexes
5. regulation of RNA splicing
6. sequestration of miRNA
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small, highly conserved non-coding RNA molecules involved in the regulation of gene expression
MicroRNAs (miRNA)
54
All cells transcribe portion of their __ into __
DNA to RNA
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form of templated polymerization that faithfully rewrites DNA to RNA
transcription
56
serves as the template to produce RNA transcripts
noncoding strand
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transcripts function as __ in the transfer of genetic information
intermediates
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guides the synthesis of proteins
messenger RNA (mRNA)
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process from DNA to protein
1. replication
2. transcription
3. protein
60
single stranded polynucleotide closely related to DNA
RNA
61
bases of RNA
- adenine
- guanine
- cytosine
- uracil
62
RNA molecules is __ and can fold up into specific shapes
flexible
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what does the shape of RNA enable
- recognize and selectively bind molecules
- catalyze some chemical changes
64
long, unbranched polymers of amino acids and are the main molecules that put the cell's genetic information into action
proteins
65
what does the amino acid sequence determine
function of protein product
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how many types of amino acids are there
20 amino acids
67
gives the protein a distinct chemical property
side chain
68
Three binding sites for tRNA
1. aminoacyl site (A site)
2. peptidyl site (P site)
3. exit site (E site)
69
all cells use proteins as __
catalysts
70
all cells acquire and utilize __
energy
71
Different ways living organisms obtain their free energy
1. organotrophic
2. phototrophic
3. lithotrophic
72
feed on other living things or the organic chemicals they produce
organotrophic
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harvest sunlight and convert it into chemical forms that can be used by the cells
phototrophic
74
capture their energy from energy-rich systems of inorganic chemicals in the environment
lithotrophic
75
- encloses all cells
- which nutrients and waste materials must pass
plasma membrane
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plasma membrane acts as a __ __
selective barrier
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determine which molecules enter the cell
membrane transport proteins
78
those that are both hydrophilic as well as hydrophobic
Amphipathic molecules / amphiphilic molecules
79
cells produce molecules whose chemical properties cause them to __ into the structures that a cell needs
self-assemble
80
covers cells and interact with substances in the environment in highly specific ways
receptors
81
how can cells respond to specific stimuli
1. altering their metabolic activities
2. move from one place to another
3. activating death pathways
82
cells are __, under constant regulation
robust
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what do cells use to regulate cellular responses to maintain homeostasis
feedback circuits
84
Universal Properties of Cells (1-3)
1. DNA is the genetic information of all cells
2. DNA is synthesized via templated phosphorylation
3. Gene is a DNA segment corresponding to one protein or RNA
85
Universal Properties of Cells (4-6)
4. All cells transcribe portions of their DNA into RNA
5. All cells translate RNA into proteins in the same way
6. All cells use proteins as catalysts
86
Universal Properties of Cells (7-10)
7. All cells acquire and utilize free energy
8. All cells function as biochemical factories dealing with the same basic molecular building blocks
9. All cells are enclosed in a plasma membrane
10. All cells respond to stimulus and self-regulate
87
new genes are generated from __ __
preexisting genes
88
randomly modifies the DNA sequence through various types of error during DNA replication
intragenic mutation
89
creates a pair of identical genes within a single cell, which may then diverge in the course of evolution
gene duplication
90
occurs when two or more existing genes break and rejoin to make a hybrid gene
DNA segment shuffling
91
Different models for DNA replication
1. Conservative model
2. Semi-conservative model
3. Dispersive model
92
Proved the semi-conservative model of DNA
Meselson-Stahl Experiment
