Unit 3 Supplemental Study Material Flashcards
1
Q
A specific sequence of DNA (composed of nucleotides: A, T, C, and G) that codes for a protein/trait (e.g., eye color, hair color).
Complexity: some traits are controlled by a single gene, many (like eye or hair color) are controlled by multiple genes (polygenic traits).
A
Gene
2
Q
some traits are controlled by a single gene, many (like eye or hair color) are controlled by multiple genes (_____ traits).
A
(polygenic traits).
3
Q
The ____ of a gene is its specific location on a chromosome
A
Locus
4
Q
different versions of the same gene that result in different traits
A
Allele
5
Q
Process during the Prophase I of Meiosis where homologous chromosomes exchange sections of DNA, mixing alleles for new variation.
A
Crossing over
6
Q
Crossing Over: Process during the ______ of Meiosis where homologous chromosomes exchange sections of DNA, mixing alleles for new variation.
A
Prophase I
7
Q
A chromosome that was originally all blue might swap part of its DNA with a chromosome that was originally all pink, creating a mix of both colors.
A
Crossing Over
8
Q
All the genetic material in a cell/organism.
A
Genome
9
Q
DNA-protein complex in the nucleus.
A
Chromatin
10
Q
Discrete “package” of DNA with genes.
Made of condensed chromatin
A
Chromosome
11
Q
____ ____:Identical copies of a chromosome, joined at the centromere post-replication.
Homologous chromosomes will replicates and make ____ ____ when it’s time to go through division
A
Sister Chromatids
12
Q
DNA region linking sister chromatids.
Used in cell division
A
Centromere
13
Q
The center of a pair of sister chromatids
A
Centromere
14
Q
*Different versions of the same chromosome, one inherited from one parent, one from the other.
*Pair of chromosomes (one from each parent) with the same genes at the same loci but potentially different alleles.
A
Homologous Chromosomes
15
Q
*Pair of chromosomes (one from each parent) with the same genes at the same loci but potentially different alleles.
A
Homologous Chromosomes
16
Q
*Different versions of the same chromosome, one inherited from one parent, one from the other.
A
Homologous Chromosomes
17
Q
Example: Humans have 23 pairs (46 total)—e.g., one chromosome 1 from mom (green), one from dad (purple), both carrying eye/hair color genes.
A
Homologous Chromosomes
18
Q
A cell or organism with One copy of each gene/chromosome (e.g., gametes).
A
Haploid (n or 1n )
19
Q
Two copies of each gene/chromosome (e.g., somatic cells with homologous pairs).
A
Diploid (2n)
20
Q
The reducing agent is the electron ______
A
donor
21
Q
The electron donor is the ____ agent
A
reducing
22
Q
The oxidizing agent is the electron _____
A
acceptor
23
Q
The electron acceptor is the _____ agent
A
oxidizing
24
Q
During what stage of mitosis does crossing over occur?
A
None. Crossing over occurs in Prophase I or Meiosis I, not mitosis.
25
Variations of a gene
Allele
26
What are the products of the Kreb's cycle?
NADH and CO2
27
Two parent cells each contribute half of their DNA via gametes, which combine to form a new organism
Sexual reproduction
28
_____ reproduction, requires meiosis, creates non-identical offspring
Sexual
29
The process that happens in cells that will create gametes
Meiosis
30
A big difference between prophase I in meiosis and prophase in mitosis is that, in prophase I of meiosis,
the chromosomes condense and a process called crossing over occurs.
31
During this phase, the replicated chromosomes (which are made up of sister chromatids) pair up with their homologous chromosomes, and crossing over takes place—this is where segments of genetic material are exchanged between them.
Prophase I
32
Once crossing over occurs, the homologous chromosomes line up along the
metaphase plate in metaphase I.
33
In _______, the homologous chromosomes are pulled apart, but the sister chromatids stay together.
anaphase I
34
During ______, the pulling apart of homologous chromosomes completes, the nuclei may start to reform, and the cell splits in half.
each resulting cell is technically 1n (haploid), each cell now has only one of each chromosome.
telophase I and cytokinesis
35
In _______, the chromosomes—still made up of sister chromatids—start to condense and line up.
prophase II
36
In _____, the chromosomes made up of sister chromatids align at the metaphase plate and prepare to be separated.
metaphase II
37
Microtubules attach to kinetochores, with centrosomes organizing the spindle fibers during Metaphase of
Mitosis and Meiosis II
38
During _______, the sister chromatids are finally pulled apart to opposite poles.
anaphase II
39
Each sister chromatid is finally considered an individual chromosome
Anaphase II
40
In ______ ______, nuclei form, the cells divide, and you're left with four haploid cells, each of which is genetically unique and none of which are identical to the original parent cell.
telophase II and cytokinesis
41
_____ are identical copies of one chromosome, linked at the centromere after S phase replication. _____ are a pair (one from each parent) with the same genes but different alleles; each can form ______
Sister chromatids are identical copies of one chromosome, linked at the centromere after S phase replication. Homologous chromosomes are a pair (one from each parent) with the same genes but different alleles; each can form sister chromatids.
42
Why might a cell spend more time in G1 than G2?
G1 involves extensive growth and organelle production, which varies by cell type and organism, while G2 is a shorter prep phase for division—duration depends on cell needs, not fixed.
43
Which phase occurs between DNA replication and mitosis?
A) G1
B) S
C) G2
D) Cytokinesis
C) G2
Explanation: G2 follows S (DNA replication) and prepares for mitosis; trick tests phase order (G1 → S → G2).
44
What is the role of binary fission in prokaryotes?
A) Creates gametes
B) Increases population
C) Repairs damaged cells
D) Produces diverse offspring
B) Increases population
Explanation: Binary fission makes identical clones, growing bacterial numbers.
45
_____ separates homologous chromosomes (sister chromatids stay together), reducing from 2n to n. _____separates sister chromatids, forming four n cells with single chromosomes.
Meiosis I separates homologous chromosomes (sister chromatids stay together), reducing from 2n to n. Meiosis II separates sister chromatids, forming four n cells with single chromosomes.
46
______ in prophase I exchanges DNA segments between homologous chromosomes, mixing alleles (e.g., purple/white flower genes), increasing genetic variation in gametes.
Crossing over in Prophase I
47
What do homologous chromosomes carry?
The same genes, but possibly different alleles (e.g., brown eyes vs. blue eyes).
48
What happens during the S phase?
DNA is copied/replicated.
49
Full Cycle:
G₁ (_____)→ S(_____) → G₂(_____) → M phase aka Mitosis (______) + Cytokinesis(_____)
G1 (growth), S (DNA replication), G2 (prep), Mitosis (DNA division), Cytokinesis (cell split).
50
Cell grows, performs normal functions, makes organelles.
Duration varies.
G1 phase, or first gap of interphase
51
DNA is replicated, chromosomes duplicate.
S phase (synthesis)
-Interphase
52
Cell grows more, final prep for division.
G₂ Phase (Second Gap)
Interphase
53
Cell theory:
cells must reproduce to support:
Growth
Tissue repair
Reproduction
54
New cells come from
New cells come from pre-existing cells.
55
_____ is the basic unit of structure and function in organisms.
The cell
56
All living things are made of
one or more cells.
57
How many total chromosomes do humans have?
→ 46 (23 pairs).
58
When are sister chromatids made?
→ During S phase of the cell cycle.
59
During metaphase, microtubules attach to structures on the chromosome called __________.
Kinetochores
60
In anaphase of mitosis, and anaphase II of meiosis, __________ are pulled apart to opposite poles
sister chromatids
61
What is the role of centrosomes during metaphase?
They organize spindle fibers that help align chromosomes at the metaphase plate.
62
During which phase do microtubules attach to kinetochores?
Metaphase
63
Glycolysis:
(Location: _____)
*Glucose is ______ (2 ATP invested).
*-----> splits into two 3-carbon molecules: glyceraldehyde-3-phosphate(____).
____undergoes reactions to produce:
2 ATP (4 produced, 2 invested).
__ NADH .
__ Pyruvate
. +Extra water and hydrogens
(Location: Cytoplasm)
*Glucose is phosphorylated (2 ATP invested).
-----> splits into two 3-carbon molecules: glyceraldehyde-3-phosphate (G3P).
G3P undergoes reactions to produce:
2 ATP (4 produced, 2 invested).
2 NADH
2Pyruvate
+Extra water and hydrogens
64
Kreb’s Cycle:
Location: ________
*Pyruvate oxidation with coenzyme A forms ______, releasing CO₂.
*_____ enters a reaction cycle that is catalyzed by enzymes producing:
Produces high amounts of high energy molecules NADH and FADH₂, Minor ATP &CO2
Kreb’s Cycle:
Location: Mitochondrial matrix.
*Pyruvate oxidation with coenzyme A forms acetyl-CoA, releasing CO₂.
*Acetyl-CoA enters a reaction cycle that is catalyzed by enzymes producing:
Produces high amounts of high energy molecules NADH and FADH₂, Minor ATP &CO2
65
Electron Transport Chain (ETC):
*Location: ____ _____ _____
*Process:
NADH moves to the ____ _____ _____
*NADH donates electrons to carrier proteins/metals (redox reactions).
*Electrons move through carriers; _____ releases & accumulate between the inner and outer layer of the _____ (_____ space).
*Oxygen accepts electrons and hydrogens, forming H₂O.
*Hydrogens pass through _____ (channel protein/enzyme), driving ADP + Pi → ATP (chemiosmosis).
*Ending Molecule(s):
ATP & Water
Total Yield: 1 glucose → 38 ATP (gross), 36 ATP (net, after 2 invested).
Electron Transport Chain (ETC):
*Location: Inner mitochondrial membrane.
*Process:
NADH moves to the Inner mitochondrial membrane.
NADH donates electrons to carrier proteins/metals (redox reactions).
*Electrons move through carriers; hydrogens releases & accumulate between the inner and outer layer of the mitochondria (intermembrane space).
*Oxygen accepts electrons and hydrogens, forming H₂O.
*Hydrogens pass through ATP synthase (channel protein/enzyme), driving ADP + Pi → ATP (chemiosmosis).
*Ending Molecule(s):
ATP & Water
Total Yield: 1 glucose → 38 ATP (gross), 36 ATP (net, after 2 invested).
66
*___ ____ is an enzyme that helps phosphorylate ADP.
*______ Using hydrogens to help phosphorylate ADP to create ATP
*ATP synthase is an enzyme that helps phosphorylate ADP.
*Chemiosmosis: Using hydrogens to help phosphorylate ADP to create ATP
67
The final electron acceptor is aerobic respiration is ____
whereas in fermentation it is _____
oxygen (inorganic); pyruvate (organic)
68
In both aerobic respiration and fermentation the electron donor is often
glucose
69
Mitosis Prophase:
1. Chromatin condenses into visible _____.
2. ____ spindle forms
(Made of centrosomes + microtubules).
3. Centrosomes begin to pull away, elongating the cell creating space for the next phase.
**Purpose: Prepares DNA and spindle for division.
1. Chromatin condenses into visible chromosomes (sister chromatids are still attached).
2. Mitotic spindle forms
Made of centrosomes + microtubules.
3. Centrosomes begin to pull away, elongating the cell creating space for the next phase.
**Purpose: Prepares DNA and spindle for division.
70
2. Prometaphase
* The ____ _____ dissolves.
*Microtubules attach to ____ on sister chromatids.
*____ is the protein structure on chromatids where spindle fibers attach.
* The nuclear envelope dissolves.
*Microtubules attach to kinetochores on sister chromatids.
*Kinetochore is the protein structure on chromatids where spindle fibers attach.
71
3. Metaphase
*Chromosomes align at the metaphase plate.
*_____ attach chromatids to microtubules from each pole.
*Centrosomes finish migrating to the cell poles.
*Chromosomes align at the metaphase plate.
*Kinetochores attach chromatids to microtubules from each pole.
*Centrosomes finish migrating to the cell poles.
72
4. Anaphase
*Cohesion proteins are cleaved to separate sister chromatids.
*Kinetochore microtubules pull chromatids to opposite poles.
*Nonkinetochore microtubules push the cell longer.
*Cohesion proteins are cleaved to separate sister chromatids.
*Kinetochore microtubules pull chromatids to opposite poles.
*Nonkinetochore microtubules push the cell longer.
73
5. Telophase
*_____ _____ begin to reform around chromosomes.
*____ reappear, and chromosomes decondense back into ____.
*Spindle microtubules dissolve.
5. Telophase
*Nuclear membranes begin to reform around chromosomes.
*Nucleoli reappear, and chromosomes decondense back into chromatin.
*Spindle microtubules dissolve.
74
Mitosis Regulation
*Protein ____activate or deactivate proteins needed in mitosis.
*____ are regulatory proteins that rise and fall with the cell cycle.
*Cell cycle checkpoints (like G1, S, G2) act as go-ahead signals.
*The __ phase is a resting, non-dividing state when division isn’t needed.
Mitosis Regulation
*Protein kinases activate or deactivate proteins needed in mitosis.
*Cyclins are regulatory proteins that rise and fall with the cell cycle.
*Cell cycle checkpoints (like G1, S, G2) act as go-ahead signals.
*The G0 phase is a resting, non-dividing state when division isn’t needed.
75
Cytokinesis
*A contractile ring made of ___ proteins pinches the cell in two.
*Results in two identical diploid daughter cells.
Cytokinesis
*A contractile ring made of actin proteins pinches the cell in two.
*Results in two identical diploid daughter cells.
