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Flashcards in Biology 1 Deck (299):
1

The intermembrane space has a ___er pH than the matrix

  • Therefore, the intermembrane space is more ____

lower pH than matrix

intermembrane space is more acidic

1

Tissue organization: ___>___>___>___

Organ systems>Organs>Tissues>Cells

1

Tetrads line up SINGLE-FILE at metaphase plate

Metaphase of Mitosis

Key word: "Single File"

2

What are the 3 main functions of PEROXISOMES? 

  1. Self-replicate
  2. Detoxify chemicals
  3. Participate in lipid METABOLISM
    • along with mitochondria

3

What are the 2 HARDY-WEINBERG Formulas we need to know?

p2+2pq+q2=1

p+q=1

3

  • Mitosis
    • Prophase 

During prophase:

  • the nuclear membrane dissolves
  • the chromosomes condense 

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3

  • Mitosis
    • Telophase

Telophase

  • is indicated by:
    • the nuclear membranes beginning to reform and
    • the chromosomes unwinding
    • Formation of the NUCLEOLUS

Many diagrams will also show the beginning of cytokinesis

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4

What are Heterotrophs?

  • UNABLE to fix CO2 (like autotrophs can)

Therefore, heterotrophs must INGEST organic molecules (such as carbohydrates) as their carbon source

5

Non-nuclear DNA is found where?

mitochondria

5

What are 4 characteristics about the NUCLEUS? 

  1. Where DNA is
  2. DNA cannot leave nuleus
  3. Is by a dual bi-layer membrane
    1. one bi layer is continuous with ER
  4. contains nuclear pores

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5

DNA replication

  • Describe DNA ligase

Creates the LAST necessary PHOSPHODIESTER bond to the downstream neighbor

thus creating a COMPLETED strand! Yayyy!!!

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6

What is the Endosymbiotic Theory?

  • suggests mitochondria evolved from aerobic PROkaryotes
    • ...that were engulfed by an ancient EUKaryotic cell (common ancestor)

7

Causes of DNA Damage

  • Mismatched Base pairs result from (2)?

HINT: One of the 2 causes results from a specific thing happening to a specific NT...

  • Give an example of this happening (with actual BP's, not a real-life example)

 

Results from:

  • Errors during replication, or
  • Methylation of guanine

ex: one form of methylated guanine pairs with thymine INSTEAD of cytosine...whoopsy daisy

8

Define a Membrane receptor

any protein that specifically binds to a signaling molecule (ligand)

  • ...and initiates a cellular response

8

  • In order for natural selection to occur, what 2 things must happen?  

HINT: Polymorphisms (discontinuous genetic variation)

1)  An individual MUST have a polymorphism that provides an evolutionary fitness advantage

2)  This advantage MUST result in the individual with the favored polymorphism

...differentially producing MORE offspring!

  • its good to be different!
  • Give a species resistance against illness & stuff

8

GLIAL CELLS, such as:

  • Astrocytes
  • Schwann cells
  • Oligodendrocytes
  • Ependymal cells

are also considered to be what?

  • Also! Remember that EPENDYMAL cells contain...?

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NERVOUS tissue

EPENDYMAL cells contain CILIA!

8

DNA replication: sliding clamp

protein that keeps DNA poly tightly bound to strand

9

How does reproduction work in Prokaryotes (Bacteria)?

  • How does the distribution of DNA work? 

Bacteria reproduce via binary fission

NO mitosis OR meiosis!

Distribution of extrachromosomal DNA (aka plasmids) is RANDOM

  • Daughter cells may or may not receive a copy

10

Define Western Blot

  • Are used for segments of ______?
  • What are used as probes?

HINT: W-e-s-t-e-r-n has 7 letters, as does the thing it sequences....

  • is for PROTEIN segments
    • instead of NT segments
  • Radioactive antibodies are used as probes
    • instead of NT sequences being used as probes

10

What is PINOCYTOSIS?

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invagination of:

  • extracellular fluid
  • very small particles

occurs in ALL cells

11

Define: Actin

a protein monomer that polymerizes to form MICROFILAMENTS

11

How does mRNA interact with DNA?

is the complementary RNA strand

...COPIED FROM the DNA template strand

13

  • What are the 6 possible destinations for ALL proteins?
    • Where are all these proteins made?

  1. ER
  2. Golgi
  3. Lysosomes
  4. Endosomes
  5. Plasma Membrane
  6. Extracellular secretion

made in: RER

13

How many layers must you go through to get from outside of the cell to the nucleus?

6 total

  • 2 for cell membrane
  • 2 for outer nuclear membrane
  • 2 for inner nuclear membrane

14

Fungi have cell ___ made of ___

cell walls made of chitin

15

What are Integral proteins?

  • What is its opposite?

Proteins that have one or more segments embedded within each phospholipid bilayer

  • opposite=surface/peripheral proteins

16

What 2 things exhibit the 9+2 arrangement?

Eukaryotic: 

Cilia & flagella

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16

Compare PROPHASE for: 

  • meiosis I and mitosis

Meiosis I:

  • Tetrads are visible paired up with e/o as nuclear membrane dissolves

Mitosis:

  • Chromosomes ARE condensed, but ARENT paired

16

Chromosomes generally _____in size, with ______ being by far the largest

generally DECREASE in size, with chromosome One being by far the largest

17

The Cytoskeleton consists of? 

  1. Microtubules
  2. Intermediate Filaments (IMF's)
  3. Microfilaments

18

In gene regulation, regulatory molecules are often what 3 things?

Regulatory molecules are often:

  1. Hormones
  2. Upstream products of rxn or cascade that is catalyzed by gene product
  3. Byproducts that build up when the [ ] of the gene product is low

18

If 90 out of every 1,000 individuals in a population have a RECESSIVE phenotype (tt)

  • what % of pop is TT, Tt, and tt?

​(Solve using HW equations)

  • 90/1000=.09 √.09=.3
    • therefore q=.3
  • since p+q=1
    • p = .72
  • pg=2(.3)(.7)=.42
  • p2=(.7)2=.49
    • therefore, 49% of pop have genotype TT
    • 42% are Tt
    • 9% are tt

70% of alleles are p and 30% of alleles are q

20

How many protofilaments surrounding a hollow core make up a microtubule?

13

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21

What are Adherens junctions?

STRONG, MECHANICAL

attachments b/t cells

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22

  • Meiosis I
    • Interphase I

23

Post-translational modification:

  • usually occurs at?
  • what are some common modifications?

  • Occurs at:
    • ER and the Golgi

Includes ADDITION of:

  • polysaccharides
  • lipids, or
  • phosphates

24

Compare anaphase for meiosis I & mitosis

MITOSIS:

  • SINGLE CHROMATIDS are pulled to opposite ends of cell

MEIOSIS I:

  • TETRADS are pulled to opposite ends of cell

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25

Cell Communication:

  • Describe Endocrine

HORMONE SIGNALING

Hormones made & secreted by cells in endocrine gland, then

  • Travel in bloodstream
  • Bind to receptors either on:
    • cell surface
      • for water-soluble hormones 
    • inside the cell
      • for lipid soluble hormones

26

Name Mendel's Laws (2) 

  • Law of...

  1. Law of Segregation
  2. Law of Independent Assortment

26

What is Bidirectional (DNA replication)?

  • Refers to fact that DNA replication proceeds in both directions (5→3, 3→​5) simultaneously 
    • Starting from the origin

28

Lysosomes

  • Have a pH of what?
  • What are the 3 main functions of Lysosomes? 

  • pH of 5

Functions:

  1. Digest cell parts
  2. Fuse with phagocytotic vesicles
  3. participate in apoptosis

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29

  • Mitosis
    • Metaphase

Metaphase is indicated by:

  • the chromosomes lining up at the metaphase plate and
  • formation of the spindle apparatus

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30

What happens to cholesterol in the cell membrane at lower temperatures?

At LOWER temps:

  • Non-polar tails of lipids could interact and cause crystallization
    • WHICH IS BAD
  • The rigid steroid portion of CHO disrupts VDW forces between lipid tails tails
    • which maintains (just enough) FLUIDITY

30

Genetics:

  • An individual having two different alleles of a particular gene or genes
    • and so giving rise to varying offspring

Would be a...?

HETEROzygote

31

____ is ALWAYS req'd to move something against its [ ] gradient or against an electrical potential

active transport

31

Describe:

 HypOtonic solutions

LESS concentrated than the cell

  • driving water to ENTER the cell
  • it might BURST!

 

water⇒cell

31

Cellular Junctions

  • Describe TIGHT Junctions

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are water-proof barriers

31

Cell Cycle: 

  • Describe the G1 Phase
  • Most active cells ___ and ___ within this phase

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First growth phase

most active cells LIVE and FUNCTION

while in this phase

  • Cell grows a ton in size during G1! 

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32

Describe what happens during CROSSING-OVER

  • When does Crossing-Over occur?

TETRADS PAIR UP with one another

and exchange segments of DNA

 

 

Occurs during Prophase 1 of Meiosis

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33

The NUCLEOLUS is the site of what 2 things?

 

Nucleolus= Nucleus WITHIN the Nucleus!

Nucleinception

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NUCLEOLUS:

Site of:

  1. rRNA TRANSCRIPTION 
  2. Ribosome assembly

 

34

Mechanisms of DNA Repair:

  • Describe Proofreading

  • DNA polymerase catches and repairs most mismatched base pairs... 

RIGHT AS IT HAPPENS!

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35

Phases of Mitosis:

  • What phase is it if you see:
    • a single cell
    • with a well-defined nuclear membrane and
    • uncoiled chromosomes?

INTERPHASE

36

Lipids are made/ synthesized in the _____,

but metabolized in the _____

  • made in SER
  • metabolized in the mitochondria

37

Bacterial growth

  • Bacterial colonies grow ________, 

    ​_____ each generation

  • Wrt Bacterial growth, there is a LIMIT to what?

    • Why is this limited?

  • Bacterial colonies grow EXPONENTIALLY
    • ​doubling each generation

HOWEVER, there is a LIMIT to colony size!

  • This is because: 
    • Food and resources decrease, and
    • Waste accumulates

37

What are ISOTONIC solutions?

  • Which direction does water flow?

have an equal [ ] as the cell

  • so there is NO net flow of water in EITHER direction

38

DNA is a polymer of WHAT?

DEOXYRIBOSE nucleotides

39

Why would fungi alternate b/t sexual & asexual reproduction?

  • Basically, what are the pros & cons of each?

Sexual is hard

  • but provides BETTER diversification

Asexual is easy (in terms of energy)

  • but provides NO diversity

40

How many primers do the Leading and Lagging strands require, respectively?

The Leading strand

  • only needs ONE primer

The Lagging strand

  • needs MULTIPLE primers
    • one for each okazaki fragment

41

Define the Spindle apparatus

SPINDLE APPARATUS

 is array of MT's that grow outward

from centrioles during mitosis

  • centrioles bind with centromeres
  • induce division of a tetrad
    • into separate chromosomes

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42

Describe the 4 steps of PCR

  • What does HEATING the DNA do?
  • Where do you add Taq Polymerase?
  • What does COOLING the mixture do?

  1. Heat DNA
    • denatures helix
  2. Add primers
    • using Taq polymerase
  3. Cool mixture
    • this anneals (recombines) primers
  4. Heat again

 

Polymerase then copies DNA

  • making 2 new DNA helices

repeat many times over

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43

Where in the KIDNEY are the following:

  • renal medulla
  • renal pelvis
  • ureter
  • nephron
  • renal cortex

Nephron:

is mostly in renal CORTEX, but dips down into the renal MEDULLA as well

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44

The Smooth ER is the site of?

Site of lipid synthesis/modification

(but NOT the site of lipid metabolism!)

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44

DNA replication:

  • What do Single-Stranded Binding Proteins (SSBP's) do? 2 things

  1. COAT the individual strands
  2. PREVENT them from re-annealing (unwinding)

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45

Main components of all viruses:

  • What 2 things do ALL viruses contain?

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ALL VIRUSES HAVE:

  • Some form of NUCLEIC ACID 
    • RNA or DNA
      • but never BOTH
  • Plus PROTEINS

46

  • Mechanisms of DNA Repair:

Describe (in general) how Nucleotide excision repair works

  • What gets removed?
    • Is that the ONLY thing that gets removed?
  • What does the repairing?

NUCLEOTIDE EXCISION

  • Removal of an oligonucleotide

...that includes SEVERAL BASES on

EITHER side of the error! (look at pic)

  • DNA poly & ligase repair the missing segment

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47

Molecular cloning:

  • What is a vector?
  • Often, the vector is a _____

  • is a segment of DNA used to transfer a desired sequence into another cell

 

often, the vector is a plasmid

48

Name the 4 types of Cellular Junctions?

  1. Tight Junctions
  2. Gap junctions
  3. Adherens junctions
  4. Desmosomes

49

Mechanisms of DNA Repair: Mismatch repair system

enzymes that scan newly copied DNA and locate, remove, and replace mismatched base pairs that DNA poly misses during proofreading

50

Apoptosis

programmed cell death, courtesy of lysosomes

51

Mitochondria have their own ___?

  • How are these passed down?

  • Have their OWN DNA and variations to nuclear genetic code
  • Mitochondrial genes are passed down through MATERNAL LINE ONLY

52

How are PHOSPHOLIPIDS formed?

  • What 3 things do you COMBINE?

​1 GLYCEROL

+

2 FA's

+

1 PO42-

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52

Define: transport proteins

Integral proteins that span entire width of bi-laye

Create tunnels for the passage of:

  • ions
  • proteins, or
  • other substances

...through the hydrophobic core

52

Genetics:

  • An individual who carries two identical copies of the recessive gene is...?

HOMOzygous RECESSIVE

 

52

tRNA

is the molecule that bridges gap b/t mature mRNA and assembled protein

53

Cause of DNA Damage: Damage by external chemicals or radiationgive an example

when exposed to radiation, neighboring pyrimidines (C or T) react with e/o to form a covalent dimerex: carcinogens are cpds that bind to DNA and create bulky side groups

54

What IS the Cytoskeleton? 

(What does it DO for the cell?)

Is a scaffolding-like network of microfilaments, microtubules, and IMF's

  • gives structure to cell
  • creates a "highway"
    • ...for intracellular transport

55

Cause of DNA Damage: Spontaneous hydrolysisgive an example

DNA reacts in solutions w/o external stimulus or chemicals ex: amine groups on DNA bases can react with water to form a carbonyl; via hydrolysis the entire DNA base can be replaced with an OH group

56

How many chromosomes do humans have...during interphase

46

57

DNA polymerase can only add to an existing ______ group

3' OH group

58

Commensalism

form of symbiosis in which one participant benefits and the other's experience is neutral (not good, not bad. It's whatevs)

59

Human taxonomy"All Cool Men Prefer Having Heavy Sideburns"

AnimaliaChordataMammaliaPrimatesHominidaeHomo Sapiens

60

Differences b/t DNA & RNA (4)

-RNA has a 2' OH group, DNA does not-RNA is single stranded, DNA is double stranded-RNA has uracil bases, DNA has thymine basesRNA exits nucleus into the cytoplasm, DNA always stays in nucleus

61

Define: Phospholipids

lipid molecules with a non-polar tail

and a polar phosphate head

  • Make up a bilayer of a cell membrane

61

Basic structure of bacteria

Capsule, peptidoglycan cell wall, plasma membrane, no complex-bound organelles, single circular DNA chromosome, tiny circular DNA molecules called plasmids

62

Phototrophs

can capture their own energy directly from the sun via photosynthesis

63

Kinetochore

specialized group of proteins to which spindle fibers attach during mitosis/meiosisoften, kinetochore is used synonymously with "centromere"

64

Define: ampiphatic

when a molecule has both polar and non polar regions (like a lipid bilayer)

65

Homologues are?

two related, but non-identical chromosomes--one originating from EACH parent

66

How many chromosomes in a diploid cell?

46

67

Fluid mosaic model

On phospholipid membrane, there are two opposite facing leaflets with polar tails of the phospholipids directed towards center of bi-layer & polar heads sticking outward-creates both a cytosolic & extracellular face

68

What does "quiescent" mean? What's an example of this?

Means stable, not changing, & unlikely to changeex: G0 phase of cell cycle

69

Aerobic respiration reactants (2) & products (3)

reactants: glucose & oxygenproducts: CO2, water, ATP

70

Anaerobic respiration reactants & products

Reacs: Glucose, electron acceptor (anything BUT oxygen)Products: CO2, whatever "thing" (which gets reduced), and ATP

71

Sister chromatids are?are they identical?

2 strands of DNA in a duplicated chromosome attached by a centromerethey are identical only if crossing over has NOT occured

72

In short, crossing over does what?

takes a father's and mother's chromosomes & swaps segments of them, thus creating new combinations of alleles on chromosomes

73

Bacteria reproduce via ?

Binary fission

74

Mitosis vs. Binary fission (bacteria)

Mitosis: very complex. Barring any errors, mitosis delivers an exact and equal amount of DNA to each new daughter cellBinary fission: circular DNA is copied and attached to the membrane. Cell splits, pulling the 2 copies apart and each new daughter cell gets one copy of the chromosome

75

Bacilli are ___ shaped bacteriaCocci are ___ shaped bacteriaSpirilla are ___ shaped bacteria

rodsphericalspiral

76

What is Tubulin?

  • a globular protein that polymerizes to form MICROTUBULES

77

Aerobic leads to complete ____ of respiratory materialproduces ___ ATP per ___

complete oxidation of respiratory materialproduces 38 ATP per glucose

78

Origin of replication

is the location on the chromosome where replication begins

79

What fills the gaps made when RNase H removes the RNA primers?

DNA polymerase

80

According to the H-W, what are the 5 conditions that will ensure evolution doesnt happen?

1) Large population2) no mutation3) no immigration or emigration4) random mating5) no natural selection

81

Hardy-Weinberg Equilibrium states that...

allele and genotype frequencies in a population will remain constant from generation to generation in the absence of evolutionary forces

82

Centromere

region of the chromosome that joins the sister chromatids

83

Mechanisms of DNA Repair: Base excision

the base portion ONLY is removed, first via a DNA glycosylase.other enzymes remove sugar-phosphate backbone, then DNA poly and ligase repair the NT

84

Define nondisjunction. What does it result in? What's a real-life example of this?

when chromosomes fail to separate properly during anaphaseresults in uneven # chromosomes--either monosomy (missing chromo) or trisomy (extra chromo) ex of trisomy: Down's

85

Name the 3 causes of DNA damage

1) Spontaneous hydrolysis2) Damage by external chemicals or radiation3) mismatched Base pairs

86

TelomerASE is?

an enzyme that adds length to the telomeres

87

Binary Fission (bacteria): remember that prokaryotes contain?

extrachromosomal DNA (plasmids)There's no system for segregating this DNA, so each daughter cell may or may not get certain plasmids based solely on random chance

88

When (at what phase of what) does crossing-over occur?

occurs during prophase of meiosis I

89

What phase? mitosis or meiosis? I or II? tetrads ("4") are visible paired up with e/o as nuclear membrane dissolves

prophase of meiosis I

90

What role does cholesterol play?

Adds rigidity and fluidity to the membrane

91

Define: Intermediate Filaments (IMFs)

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Several proteins that polymerize to form filaments that are: 

  • INTERMEDIATE in diameter b/t:
    • microfilaments (smallest)
    • microtubules (largest)

92

Diploid cell has __ chromosomes

2n

93

G protein cascade: What activates protein kinase A (PKA)?What does PKA do?

-cAMP-PKA phosphorylates proteins, usually enzymesBOOM! Cascades

94

Remember that all bacteria are ______

prokaryotes

95

Why is G0 phase of interest in the MCAT?

-b/c fully-differentiated neurons & cardiac muscle cells are frozen in G0 and do not divide-Multi-nucleated skeletal muscle cells are also in G0

96

DNA replication: What is the helicase?

it unzips the double-helix

97

Define: cancer

uncontrolled cell division due to failure of cell's normal regulatory patterns

98

Tools scientists use to determine taxonomy (5)

1) embryology- often two organisms have similarities that are only present during embryological development 2) Phylogeny- a shared evolutionary history can reveal similarities3) Anatomy4) DNA sequencing 5) Fossils- can reveal traits that were once shared but have since been lost

99

Sex-linked chromosomes: male=?female=?

male=Xfemale=Y(draw a punnett square)

100

name the Mechanisms of DNA repair (4)

1) proofreading2) mismatch repair system3) base excision4) NT excision

101

Phases of Mitosis: Anaphase

here, chromosomes separate and migrate towards the opposite ends of the cell

102

Methods of cell communication (6)

1) Endocrine2) Paracrine3) Autocrine4) Intracrine5) Juxtacrine6) Nervous System

103

What are Cilia?

 

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protrusions found in:

  • the lumen-facing side of EPITHELIAL cells lining various cavities in the body

104

Typical phenotypic ratio for a dihybrid cross

9:3:3:1

105

Cytoskeleton

  • Define a Microtubule

  • one of 3 parts of cytoskeleton of cell
  • Made up of 13 protofilaments
    • which are made when ß and α-tubulin form a heterodimer

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105

Define "mutation"

any change in the DNA sequence

105

Lichen: symbiosis b/t what?

b/t fungi and algae

105

Hypertonic solutions

more concentrated than the cell, driving water to LEAVE the cellSHRINKS!

105

G protein cascade: Alpha subunit does what?

-binds both GTP and GDP-activates cAMP (which converts ATP to ADP + 2Pi)

105

Semi-discontinuous (DNA rep)?

refers to fact that one strand (leading strand) is synthesized continuously, which the other strand (lagging) is synthesized in okazaki frags (is discontinuous)

105

Telomeres are?

-long sections of repetitive DNA NT's found at both ends of each chromosome-provide a buffer regions of non-coding DNA so that the repetitive losses in length don't impact the gene sequence

106

When forming PHOSPHOLIPIDS, how does the reaction work? 

  • What does the glycerol do to the FA? 
  • What happens as a result?
  • What NEW thing is formed?

FA is a long chain carboxylic acid

  • one of the OH groups on the glycerol attacks the carbonyl carbon
    • kicking off a H20 molecule
      • & forming a new ester group

107

Eastern Blot defwhat do probes bind to?

used to verify post-translational modification-probes bind to lipids, carbohydrates, or phosphates (the 3 most common post translational modifications)

108

Muscle tissue

includes skeletal, smooth or cardiac muscles found anywhere in the body

109

G protein cascade: alpha subunit does what?

binds both GTP and GDP

110

Phases of Mitosis: Telophase

here, nuclear membranes begin to re-form and chromosomes unwind

111

What's the difference b/t: 

Eukaryotic vs Prokaryotic Flagella?

Eukaryotic:

  • whipping motion
  • microtubules
    • made of tubulin

Prokaryotic:

  • spinning/rotating motion
  • simple helices
    • made of flagellin

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112

Fungal reproduction (4)

-fungi spend the majority of their life as a haploid (have a single set of unpaired chromosomes)-fungi grow via long, intertwining branches called hyphae (which are haploid)-Yeasts reproduce almost exclusively by budding-Most fungi can reproduce both sexually (what life is hard...stress, little food, etc) or asexually (when life is good)

113

Tissue types (4)

1) epithelial2) nervous3) connective4) muscle

114

How many chromosomes do humans have...before replication?

46

116

Gene regulation: rate of transcription

RNA has a short half-life, so gene products will only continue to be expressed if DNA is continually transcribed

117

What stage? Mitosis or meiosis? I or II?chromosomes condensed, but not paired

prophase of mitosis

119

Pinocytosis is non-____, whereas phagocytosis is always ___-mediated

non-specificreceptor mediated

120

Fungi (3 examples)

mushrooms, yeasts, and molds

121

How do lysosomes FORM?

by budding off from the Golgi

122

Meiosis I takes a cell with __ homologous chromosomes (or__ totoal chromosomes) and creates?

23 homologous chromosomes, or 46 total chromosomescreates 2 cells, each with 23 non-paired, non-homologous chromosomes

123

Post-translational modification

  • Starts where and
  • Continues on to where?

Give 2 examples of PTM's

  • Starts in RER
  • continues on to Golgi

ex: disulfide bonds, glycosylation

124

Genetic Regulation:

  • Describe the LAC OPERON
    • What does it regulate? 
      • What does the thing it regulates DO?

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Regulates EXPRESSION and TRANSLATION of LACTASE in bacteria (E. coli)

  • Lactase is the enzyme that digests lactose

Remember:

  • Bacteria do much more anaerobic respiration (fermentation⇒lactose)
    • so they will have a MUCH larger problem if lactose starts building up than if it were to happen in humans 

125

Cell Cycle: M phase

mitosis happens during this phase

126

Mendel's Laws: Law of Segregation

alleles segregate independently of one another when forming gametes

127

Describe the CENTROSOME (3 things)

CENTROSOME:

  • Is an amorphous area of proteins which contain CENTRIOLES 
  • Organizes: 
    • microtubules
    • flagella
    • cilia
  • Plays a role in APOPTOSIS (cell death)

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128

Autotrophs

capable of fixing CO2, and can therefore use CO2 as their carbon source for synthesizing organic molecules

129

Define: Microfilament

  • part of cytoskeleton
  • also forms the "thin filament" portion of sarcomere

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131

Parasitism

symbiosis where one participant benefits at the expense of the other (other participant IS harmed!)

132

Typical phenotypic ratio for a monohybrid cross

3:1

133

Gap Junctions

tunnels b/t adjacent cells, which allow exchange

134

Molecular cloning: recognition sequence

is the specific base sequence recognized by the endonuclease

136

Stages of Anaerobic respiration (3)?This is the same as in what else?

glycolysiskrebs cycleETC (same as in aerobic respiration)

137

G protein cascade: How do you shut down the cascade? (one way)

-Beta & gamma subunits re-bind with alpha subunit, deactivating it

138

Desmosomes

STRONGEST of cellular junctions-they weld cells together, protecting against stress-are NOT watertight (only tight junctions are)

139

Epithelial tissues

form the linings of the outside of the body, as well as various cavities INside the body. if it is lining a cavity or separating the body from the external environment, consider it to be epithelial tissue

140

When DNA is replicated, the ____ ___ does NOT change---you just end up with twice as much ___ per ___

chromosome number doesnt changetwice as much DNA per chromosome

141

Phases of Mitosis: Metaphase

here, chromosomes line up at the metaphase plate and form the spindle apparatus

142

Chromosomal Mutations: (4)

-duplications (non-disjunction)-deletions (non-disjunction)-translocations-inversions

143

Define: Cholesterol

-an ampiphatic molecule with a steroid region and a polar region-inserted in b/t phospholipids in high [ ]s in euk. cells

144

Molecular cloning: restriction nucleases

enzymes that cut DNA at specific pre-determined sequences

146

What makes CILIA different from FLAGELLA?

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Cilia are NOT used for locomotion of the cell itself

  • Cell is fixed in place
  • Cilia creates a beating pattern
    • that moves fluid and other things PAST the cell

147

ATCGWhich are purines & which are pyridines?

GA= purines (General Authorities are pure)CT= pyrimidines

148

Genetics:

  • Any...
    • VARIANCE from expected ratios, or
    • RANDOM ASSORTMENT

Suggests WHAT?

LINKAGE!

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149

What does REVERSE TRANSCRIPTASE do?

  • What "idea" does reverse transcriptase VIOLATE?

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REVERSE TRANSCRIPTASE

  • Found in Retroviruses
  • Translates its RNA nucleotide sequence into DNA
    • because RNA wasnt able to be inserted into the host's genome

RNA⇒DNA

VIOLATES THE CENTRAL DOGMA OF MMBio:

The "central dogma" of molecular biology describes the flow of genetic information in cells from:

DNA⇒RNA⇒protein

  • It states that genes specify the sequence of mRNA molecules
    • which in turn specify the sequence of proteins 

150

Cell Communication: Nervous system*this method often involves what?

Communication b/t cells via electrical potentials carried on neurons*these often involve cascades, too. Neurotransmitters bind to receptors on post-synaptic membrane, which initiates a signal

151

Phagocytosis

-type of endocytosis-refers to invagination of very large particles, bacteria, etc-only happens in a few types of cells

152

Fungi traits

all fungi are heterotrophs. Most are saprophytic (live off dead, decaying matter), but a few are parasitic (live off live host, killing it), or mutualistic (symbiotic relationship)

153

Molecular cloning: hybridization means what?

means to join together to form a single strand

154

Genetic probabilities: "EITHER/OR"

If EITHER event occurring fulfills the requirement, add the probabilities of each event occurring individually

155

How many chromosomes do humans have...after replication

46

156

Nervous tissue

neurons of central & peripheral nervous systems

157

  • Each time a DNA strand is replicated, the new strand is always slightly ____ that the parent strand
  • Why is this?

SHORTER

  • b/c DNA polymerases need an existing 3' OH group

to add their first NT to

  • they can't replace that section of primer

158

What is CHROMATIN?

  • what's an example of something made of chromatin?

  • general term for "DNA+protein"

CHROMOSOMES are made of chromatin

DNA+Histones

159

Cell Cycle: interphase

entire period OUTSIDE of mitosis

160

Lytic (cycle of) viral reproduction

-period during which viral genes are actively being transcribed and new viruses are being assembled. -During this phase, infected cells BURST!! to release large #'s of new viruses

161

G protein cascade: GDP is bound when protein is ___GTP is bound when protein is ___

GDP--offGTP--on

162

is rRNA an enzyme?

Not by itself, but when it assembles into a ribosome it can

163

Where are all of the places Microtubules could be found?

HINT: Where there's Cilia, there are MT's

(^^Theres a few other places you'd find MT's too^^)

 

  • The 3 places cilia are
    1. lungs
    2. ependymal cells
    3. uterine cells
  • In the flagella of sperm
  • In ALL cells
    • as part of the cytoskeleton & spindle apparatus

164

What are Flagella?

  • What are they used for?
  • What are the ONLY cells that have flagella?

Flagella:

  • whip-like projections from the cell body
  • used for locomotion
  • Human sperm cells are the only cells that have flagella

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165

When is the only time chromosome number changes? (2)

1)during meiosis2) after fusion of gametes in the production of a zygote

166

G protein cascade

  • G protein is made up of what 3 subunits?

α

β

γ

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167

Making genetic predictions for Dihybrid crosses--in the SAME individual

-Draw out 2 punnett squares (one for each trait) -To calc probability of 2 traits in the same individual, multiply the individual probabilities of each trait

168

rRNA

(ribosomal RNA)is the polymer of which ribosomes are constructed

169

Gene regulation

  • Describe Activators & Repressors

Give an example of both, using the Lac Operon as a scenario

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Regulatory molecules can either:

1) UPregulate DNA transcription

  • ex: lactose in the lac operon 

2) DOWNregulate transcription

  • ex: glucose in lac operon

170

Major purpose of chromosomes is to...?

efficiently package the SUPER LONG DNA strands, so they can easily be stored b/t divisions and moved during division

172

Cell Cycle: G0

-cells that enter this phase become non proliferative-basically, there arent actively dividing (and may not in the future)-Many full-differentiated Eukaryotic NEURONS remain in this phase indefinitely

173

What stage? Mitosis or meiosis? I or II?Tetrads line up IN PAIRS at metaphase plate

metaphase of meiosis I

174

endocytosis

where a cell takes up small particles by lumping into the plasma membrane, forming a vesicle called an endosome

175

Second messenger systems

-water-soluble hormones or signaling molecules bind to mem receptors on external surface of plasma membrane-this binding rarely stimulates immediate response from cell--more often it initiates a cascade that increases size of signal, which eventually stimulates cellular response

176

What would happen if crossing over didn't occur?

All of the genes on one chromosome would always demonstrate linkageLOSS OF GENETIC VARIATION! WHICH IS BAD!

177

name the 3 components of NT's

1) triphosphate2) sugar3) base (one of four: ATCG)

178

Northern Blot

for RNA sequences

179

Prokaryotes vs Eukaryotes differences

Pro: have no nucleus, no membrane-bound organelles, they have circular DNA, no histones or chromosome struc, and 70S(50S & 30S) ribosomesEuk: have a nucleus, mem-bound organelles, linear DNA with histones * chromosome struc, and 80S(60S and 40S) ribosomes

181

Genes are regulated via 3 basic mechanisms. name them.

1) rate of transcription2) Activators and repressors3) permanent or semi-permanent suppression

182

If a male with a sex-linked recessive disease has children with a normal woman, ?

All of his daughters (XX) will be carriers

183

Adenine (A), pairs with?

T via 2 hydrogen bonds

185

________s are a very common second messenger system that the MCAT loves to question you on

G-proteins!

186

Gram Positive vs Gram Negative: describe gram (+)

Gram Positive: -stain purple-very thick cell wall-form endosomes-Single cell membrane

187

In humans, cilia are found exclusively in what 3 SYSTEMS?

  1. Respiratory system
    • lungs
  2. Nervous system
    • ependymal cells
  3. Reproductive system
    • uterine tubes

188

Golgi Apparatus

  • What are its 3 main jobs?

  • Organize proteins
  • Continue post-translational modification
  • Excrete proteins in vesicles bound for:
    • Plasma membrane
    • organelles, or
    • BACK to the ER (retrograde transport)

189

Types of membrane transport (4)

1) simple diffusion: no ATP req'd2) facilitated diffusion: No ATP req'd (ex: osmosis)3) active transport: ATP req'd4) Secondary active transport: no DIRECT coupling of ATP req'd

190

Anaerobic respiration occurs mostly in?

Prokaryotes

191

  • Mitosis 
    • Anaphase 

Anaphase is indicated by:

  • separation of the chromosomes and
  • migration toward the opposite poles of the cell

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193

Compare metaphase for meiosis I and metaphase

meiosis I: tetrads line up IN PAIRS at the metaphase platemitosis: tetrads line up SINGLE-FILE at metaphase plate

195

Cell Communication: Juxtacrine

signaling req's direct contact b/t two cells

196

Crossing over happens to such an extent that two genes must...?

be VERY close to e/o on the chromosome to NOT assort independently (aka linkage...which is bad)

197

Differentiate b/t aerobic & anaerobic respiration

aerobic uses oxygenanaerobic doesnt use oxygen--DOES use an ETC, but doesnt use O2 as the e' acceptors

198

Connective tissue

bone, cartilage, blood, lymphatic tissue, fat, etc. basically, if a cell is obviously not epithelial, nervous, or muscle, it's probably connective

200

Mycorrhizae: symbiosis b/t what?

b/t fungi and plant roots

202

What happens to cholesterol in the cell membrane at higher temperatues?

non-polar region of CHO interacts with hydrophobic tails of lipids, holding them in place and this adding RIGIDITY

203

G protein cascade: what causes conformational change that activates cytosolic domain of an integral protein?

when a hormone or signal molecule binds to the GPCR

204

Cell Cycle: S phase

DNA replicated here

205

Mendel's Laws: Law of Independent association

genes located on different chromosomes assort independently

206

Function of glomerulus

capillary bed that strains the blood-allows fluids, ions, & molecules around the size of GLUCOSE (or smaller) to pass through Bowman's capsule-anything bigger will remain in the capillaries and exit via the efferent arteriole, which eventually empties into the renal vein

208

ALL proteins bound for cytosol

plus SOME proteins bound for other organelles

are made on ?

Free-floating RIBOSOMES in the cytosol

209

haploid cell has __ chromosomes

n for humans, n=23

211

Southern Blot

verify presence of DNA sequencesalso indicates relative size of restriction fragments

213

  • Explain the GRADIENT across inner mitochondrial membrane
    • What happens if you were to insert H+ channels within the membrane?

intermembrane space has higher hydrogen ion [H+] concentration, so it is more acidic

  • adding H+ channels would give H+ ions an ALTERNATE pathway back into the matrix OTHER than going solely via the ATP synthase
    • as a consequence, ATP production would decrease

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215

p^2+2pq+q^2=1p+q=1What do p, q, p^2, and q^2 represent?

p & q refer to % of each ALLELE present as a fraction of all the alleles in the population-p^2 represents fraction of INDIVIDUALS who have homozygous dominant genotype (TT)-q^2 represents faction of individuals with the heterozygous genotype (tt) ***in short: p and q represent fractions of p and q ALLELES in the population***q^2, 2pq, and q^2 represent fractions of INDIVIDUALS with each possible genotype

216

What cellular junction is the STRONGEST of the four?Where might you find this type, and why?

Desmosomesfound in tissues that receive high amounts of shear stress, like the epidermis

217

DNA replication: RNase H

removes all RNA primers

218

Cytosine (C), pairs with?

G via 3 hydrogen bonds

219

Semi-conservative (DNA rep)?

refers to fact that each of newly formed daughter helices is made up of one OLD strand plus one NEW strand

220

Bacteriophages

viruses that infect bacteria-have a capsid head, tail, tail fibers, etc.(typical virus looking thingy!)

221

Many enzymes are activated by?

Phosphorylation!

222

Genetics: How to make predictions. What should you always do FIRST?

Draw a punnett square

223

Where are steroid membrane receptors located? Why?

in the nucleusbecause steroids can diffuse through the hydrophobic membrane core (dont need a transport protein)

224

"-tase" means it is?

an ATP-requiring enzyme!!!

226

Vaccine definition & why do vaccines become less effective with time?

-is an inactive portion of a virus delivered to a person so their immune system can develop antibodies against the virus, without actually being infected by it-they become less effective b/c of SUPER FAST viral mutations!

227

Thymine (T), pairs with?

A via 2 hydrogen bonds

228

Function of proximal convoluted tubule (PCT)  

-section of nephron b/t bowman's capsule & descending limb of the loop of henle-along PCT Na+ is reabsorbed via active transport & glucose is reabsorbed via secondary active transport-since water and solutes are reabsorbed in the same ratio, the filtrate remains ISOTONIC

229

Cell Cycle: G2

comes after S. -cell continues to grow & has high metabolic activity (esp. production of microtubules in preparation for mitosis)

230

Taxonomy"Do Kings Play Chess On Fridays, Generally Speaking?

DomainKingdomPhylumClassOrderFamilyGenusSpecies

231

What will you assume if you're asked to predict the genotype of offspring when you are NOT given info on ONE of the parents?

assume the other parent is NOT affected, thus NOT a carrier of whatever

232

MYOSIN is a ___, not a ___

MOTOR PROTEIN

NOT a microfilament!!

234

Cell Communication: Autocrine

signal molecules secreted by a cell bind to receptors ON THAT SAME CELL

235

"The Species Distinction"

organisms classified as different species should not be able to mate with one another and produce viable, fertile offspring

236

What is the 9+2 format?

  • NINE doublets (2 microtubules each) surrounding a CENTER doublet (2 microtubules) in a wheel-like design

Total of 20 microtubules (18+2)

  • Each of these microtubules are made up of 13 protofilaments

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238

What are some things that trigger cell apoptosis? (4)What's something else apoptosis does apart from removing bad cells?

extreme heatradiationviral infectionDNA damage, etcCan also remove healthy, but unwanted cells

240

Gram Positive vs Gram negative: describe gram (-)

-stain pink-relatively thin cell wall-do NOT form endosomes-contain 2 cell membranes: one inside the cell wall and one outside the cell wall

241

exocytosis

vesicle on inside of membrane fuses with plasma membrane & dumps its contents into extracellular space

242

Define: Thin filaments of the sarcomere

  • Formed from microfilaments

Thin filaments act as a TRACK along which THICK FILAMENTS move during contraction

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244

Making genetic predictions for dihybrid crosses-- "for __ # of individuals" w/ a phenotype or genotype

-If # of individuals with a specific genotype or phenotype is asked for, multiply the total probability of having BOTH traits by the total number of offspring

245

Meiosis Yields:

4 genetically distinct HAPLOID daughter cellsCentromeres do NOT split during meiosis I, but do during meiosis II

247

Cell Communication: Paracrine (plus example)

signal molecules secreted by one cell bind to receptors on other cells in the local area. ex: neurotransmitters acting in the synaptic gap

248

How many chromosomes in a haploid cell?

23

249

Molecular cloning: gel electrophoresis

lab technique used to separate molecules by size

250

Gene Regualtion: permanent or semi-permanent suppression

Methylation or other covalent modification that prevents or dramatically DECREASES transcription

251

What are Thick filaments made of?

What do they move along, and during what?

  • Made up of MYOSIN (motor proteins)
  • move along thin filaments
    • during contraction

252

Lysogenic (cycle of) viral reproductionexample?

-is the dormant cycle of the virus during which time viral DNA is incorporated into the host's genome, but new viruses are not being assembled. ex: HIV infection without having AIDS symptoms

253

Chemotrophs

oxidize organic or inorganic cpds to harvest energy

254

Phases of Mitosis: prophase

nuclear membrane dissolves and chromosomes condense

255

Do mitochondria use the same genetic code to translate their DNA?

NOPE

256

Genetics: what is assumed for an individual with the DOMINANT phenotype?

Homozygous dominant

257

Anaerobic respiration takes place where? (2)

Cytoplasm & mitochondria

258

Do all human traits follow the Mendelian pattern?

NOPE! Most dont, actually.

259

"Wild Type" =?

the normal or typical phenotype

260

Mitosis yields

2 genetically IDENTICAL diploid daughter cells, which are genetically IDENTICAL to the mother cell that produced them*The centromeres split*

261

histones

proteins around which DNA helix is wrapped when condensed into chromosomes

262

DNA replication: DNA polymerase reads in _____ direction, thus builds new strands in the ___ direction

3' to 5' builds new strands in 5' to 3' direction

264

DNA replication is: (3) name the traits

bi-directionalsemi-conservativesemi-discontinuous

265

"-ase" means it is ?

an enzyme

266

Guanine (G), pairs with?

C via 3 hydrogen bonds

267

DNA replication: What does the primase (which is an ___) do?

(which is an RNA polymerase)constructs short RNA primers on both strands

268

Mutualism

form of symbiosis where both parties benefit equally

269

nucleosomes

set of 8 histone proteins in a cube shape with DNA coiled around it.

270

Microfilaments are made up of ___ subunits

actin subunits

271

Genetic probabilities: "BOTH/AND"

if both events occur simultaneously, multiply probabilities of each event occurring individually

272

What besides DNA and RNA are nucleotides present in?

Telomerase & ribosomes have bits of attached RNAATP has NT's too

273

Define: Surface ("Peripheral") proteins

  • Where are they ENTIRELY contained/found?

Proteins on a cell membrane that DONT enter into hydrophobic core

  • contained entirely on polar surface of membrane

274

Genetic Regulation

LAC OPERON:

How much synthesis of lac mRNA can you expect if:

  • You have BOTH lactose (activator) AND glucose (repressor) present

Since Glucose IS present, you'll have low cAMP 

cAMP unable to bind & activate CAP, which is unable to help RNA Poly bind to the Promoter region 

 

Since RNA Poly is LESS LIKELY to bind to promoter region:

  • you'll have VERY LITTLE lac mRNA synthesized

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275

Genetic Regulation

LAC OPERON:

How much synthesis of lac mRNA can you expect if:

  • Lactose (activator) is PRESENT, and Glucose (Repressor) is SCARCE?

EXPLAIN WHY!

Since glucose is SCARCE,

cAMP IS able to bind to CAP

  • This enables RNA Poly to easily bind to the PROMOTER region

=HIGH LEVELS of lac-mRNA synthesis

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276

MEIOSIS I

  • Takes a cell with __ pairs of _________ chromosomes (or __ total chromosomes)
  • ...and creates _ ____
    • Each with __ non-_____ed, non-_________ chromosomes 

MEIOSIS I 

  • Takes a cell with 23 pairs of homologous chromosomes, or 46 total chromosomes
  • and creates two cells
    • each with 23 non-paired, non-homologous chromosomes

277

Generally speaking, chromosomes tend to ______ in size throughout the cell cycle

Example

In Meiosis I, You start with 23 homologous chromosomes

  • Which of those 23 chromosomes will be the LARGEST? 

DECREASE!

1 >>> 23

Chromosome ONE is BY FAR the LARGEST chromosome! (Always!)

278

During cell division, are chromosomes DUPLICATED?

  • How do levels of DNA and Chromosomes vary during cell division?

Chromosomes are NEVER "duplicated" 

in number during cell division

They are “REPLICATED

  • meaning each single chromosome gains an identical sister chromatid

...but only the amount of DNA has INCREASED

...the # of chromosomes has NOT!!!

 

  • Before DNA replication each cell will have 46 chromosomes 
  • Afterward each cell will still have ONLY 46 chromosomes

279

Which of the following statements is/are TRUE regarding human chromosomes?

I. In their condensed form they contain a large amount of protein

II. They are in their condensed form for the majority of the cell cycle

III. They contain nucleosomes

IV. There are 46 non-identical chromosomes in each somatic cell

  • A. II and IV
  • B. I and III
  • C. I, II and III
  • D. I, III and I

D

Statement I is true

  • Chromosomes contain many histones
    • which are a type of protein

Statement II is false

  • During most of the cell cycle the chromosomes are unwound
    • Not until prophase do the chromosomes condense

Statement III is also true

  • A nucleosome is a set of four histones wound together

Statement IV is true

  • You may be tempted here to think that we only have 23 pairs of non-identical chromosomes because of the existence of homologues
    • That would be true IF homologues were identical
  • However, homologues are definitely non-identical because they contain a random assortment of alleles

280

What is a PROTEIN that is very abundant in CHROMOSOMES? 

  • HINT: Chromosomes package DNA.....

 

HISTONES! 

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281

During most of the cell cycle, CHROMOSOMES are wound/unwound?

  • It's not until _____ that the chromosomes _____

During most of the cell cycle, 

chromosomes are UNWOUND

Not until PROPHASE do the chromosomes CONDENSE

282

Define a NUCLEOSOME

  • Where could you find them?

a nucleosome is a set of four histones wound together

  • Found in CHROMOSOMES!

REMEMBER:

Chromosomes package DNA 

Where there's DNA, there Histones, & where there's Histones there's Nucleosomes

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283

There are ALWAYS __ chromosomes in a somatic cell before, during, and after MITOSIS

46!!!

284

Uptake of glucose from the gut and transport of K+ ions through the voltage-gated channels of a neuron are best described as:

  • A. secondary active transport and active transport, respectively
  • B. active transport and facilitated diffusion, respectively
  • C. secondary active transport and facilitated diffusion, respectively
  • D. active transport and diffusion, respectively

C

Uptake of glucose at both the gut and the kidney is accomplished via a secondary active transport system--

Meaning that a “secondary” molecule is actually the one actively transported

  • in order to get the molecule of interest into or out of the cell

In this case, sodium is transported against its gradient

  • where it pairs with glucose
    • and brings it back into the cell
      • back down sodium’s gradient

The flow of K+ ions thru a potassium channel in the neuron does NOT involve ATP, 

  • and is thus REGULAR diffusion

However, because it goes thru a CHANNEL PROTEIN, it is considered “facilitated diffusion” 

285

Which of the following is NOT a function of the endoplasmic reticulum?

  • A. detoxification of cellular chemicals
  • B. lipid production and metabolism
  • C. synthesis site of extracellular proteins
  • D. post-translational modification of proteins

B

The ER, between the smooth and rough sections, is responsible for:

  • Detoxifying chemicals
  • producing lipids
  • synthesizing extracellular proteins
  • modifying translated proteins
  • and various other functions

The key here is that lipids are

MADE at the smooth ER...

...but are METABOLIZED in the

MITOCHONDRIAL MATRIX!!!

Thus B is a false statement and is the correct answer

286

DESMOSOMES are found in tissues that receive a lot of ____  and ____, such as _______ cells

 

REMEMBER: Desmosomes are the strongest of the 4 cell junction types

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Desmosomes are found in tissues that receive a lot of PRESSURE and IMPACT 

  • such as epithelial cells

287

Describe SUBSTRATE-LEVEL PHOSPHORYLATION

  • Where's one place this happens? 

Substrate-level phosphorylation 

is a type of metabolic reaction that results in the formation of  ATP or GTP by:

  • the DIRECT TRANSFER of a PHOSPHORYL GROUP(PO3)
    • ....to ADP or GDP
    • from a phosphorylated reactive intermediate

This happens in the KREBS CYCLE!

GDP is phosphorylated into GTP

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288

What is it that INTRONS are spliced out of?

Introns are removed from pre-mRNA

(NOT replicated DNA!)

289

The DNA strand shown below is from the CODING (!) strand of a section of human DNA

Which of the following gives the matching pre-mRNA sequence?

5’ATTCG3’

  • A. 5’UAAGC3’
  • B. 3’UAAGC5’
  • C. 3’GCUUA5’
  • D. 3’AUUCG5’

C

5’ATTCG3’ 

3’GCUUA5’ 

  • To answer this correctly, you must differentiate “coding strand” from “template strand.”

The template strand is the one copied

The coding strand is the other strand

  • the complement to the template strand
    • which is NOT copied

As a result, the:

  • new DNA strand OR
  • the new pre-mRNA strand

will be an EXACT COPY of the coding strand

(EXCEPT, in the case of pre-mRNA, T will be replaced with U)

  • The next skill you need is to keep careful track of the 3’ and 5’ ends
  • Normally, we need the strands to run in opposite directions
    • (so if the template strand was listed 5’ to 3’ the new strand would consist of the matching base pairs running 3’ to 5’)

However, note that here you are NOT given the template strand, but the coding strand

Thus, the coding strand and the new pre-mRNA strand will both run the same direction and will be identical

  • except for replacing T with U

290

IMPORTANT!

  • GENES can only produce WHAT?
  • You cannot have a gene transcribed, and then translated into a _____, a ___, or anything else.

 Genes can ONLY produce PROTEINS!

 DON’T FORGET THIS!

  • You cannot have a gene transcribed and then translated into a carbohydrate, a fat, or anything else

291

HYPOTHETICALLY:

​Hormone QReceptor P ⇒activates adenyl cyclase ⇒converts ATP to cAMP ⇒leads to phosporylation of Protein Z, which actively transports Glucose into cell

***

If you needed to QUICKLY remove Glucose from the cell, inhibiting which of the above things would do it FASTEST? Why?

DEPHOSPHORYLATING

PROTEIN Z

  • Stopping the final step in the chain
  • In this case, it will not matter what previous molecules are still present

If you were to remove all of Hormone Q, for example, you'd still have to wait for whatever was there right BEFORE removing it to make its way through the cascade

292

LYSOGENIC vs. LYTIC

Which is the "DORMANT" cycle?

Will it always be dormant?

LYSOGENIC=DORMANT

  • It is inevitable that at some future time, usually during a time of stress, the virus WILL become “lytic”
    • and commandeer the host’s machinery to actively produce virions

293

FUNGI

  • They have cell walls containing _____ 
  • They are _____ during most of their life cycle
  • They ____ food before _____ing it
  • They are capable of both _____ and _____ reproduction

  • They have cell walls containing CHITIN
  • They are HAPLOID during most of their life cycle
  • They DIGEST food before INGESTing it 
  • They are capable of both SEXUAL and ASEXUAL reproduction

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