Bio 120 Exam Ii

Front 1

Net Equation of Cellular Respiration

Back 1

C6H12O6 + 6 O2 >> 6 CO2 + 6 H2O + 32 ATP + heat

Front 2

What is happening during cellular respiration?

Back 2

Glucose is being oxidized to CO2 and O2 is being reduced to H20.

Front 3

Oxidation and Reduction

Back 3

The transfer of electrons

Oxidation: to lessen in electron density

Reduction: to increase in electron density

Front 4

Four Stages of Cellular Respiration

Back 4

1. Glycolysis (cytosol)

2. Pyruvate Oxidation (mitochondrial matrix)

3. TCA (Citric Acid, Krebs) cycle (mitochondrial matrix)

4. Oxidative Phosphorylation (inner mitochondrial membrane)

Front 5

Glycolysis(cytosol)

Back 5

a. Glucose (6C) >> 2 pyruvate (3C)

b. Net gain of 2 ATP (via substrate-level phosphorylation)

c. Reduction of 2 NAD+ to NADH

Front 6

Pyruvate Oxidation (mitochondrial matrix)

Back 6

a. Pyruvate (3C) >> acetyl CoA (2C) (so two acetyl CoA per glucose molecule)

b. Reduction of one NAD+ to NADH (again, two per glucose)

c. Loss of CO2 (1C) (again, two per glucose)

d. Acetyl CoA feeds into the TCA cycle

e. NADH feeds into oxidative phosphorylation

Front 7

TCA (Citric Acid, Krebs) cycle (mitochondrial matrix)

Back 7

a. Acetyl CoA(2C) >> CO2 per turn

b. One acetyl CoA yields 1 ATP 3 NADH, and 1 FADH2 per turn.

Front 8

Oxidative Phosphorylation (inner mitochondrial membrane)

Back 8

a. NADH and FADH2 provide electrons, which are transported along the electron transport chain of the inner mitochondrial membrane.

b. 02>>H20 and is the ultimate electron acceptor

c. Electron transport generates a proton gradient.

d. ATP synthase uses this gradient to make ATP e. 2.5 ATP per NADH and 1.5 ATP per FADH2.

Front 9

Fermentation

Back 9

If oxygen is limiting, e.g. during peak muscular exercise, or if you lack mitochondria like bacteria, pyruvate, which is the end product of glycolysis, cannot be oxidized further.In these cases, pyruvate is reduced to lactate (lactate fermentation) or decarboxylated and then reduced to ethanol (alcohol fermentation).

Front 10

Autotroph and Heterotroph

Back 10

Autotroph – makes its own food.

Heterotroph – must take in food; this means eating plants or eating animals that have eaten plants

Front 11

Mesophylls

Back 11

photosynthetic cells in plant leaves

Front 12

Stomata and guard cells

Back 12

structures in plant leaves that regulate gas exchange

Front 13

Chloroplast

Back 13

photosynthetic organelle

Front 14

Stroma

Back 14

thick fluid within inner membrane; site of ATP synthesis

Front 15

Thylakoid

Back 15

membranous sacs; contain chlorophyll and electron transport chain

Front 16

Net Equation of Photosynthesis

Back 16

6 CO2 + 6 H2O >> C6H12O6 + 6 O2

Front 17

Two Stages of Photosynthesis

Back 17

Light Reactions: Takes place in thylakoid. Chlorophyll captures the energy of sunlight, to make ATP and NADPH,with O2 as a by-product.

Calvin Cycle: Uses energy from light reactions (ATP and NADPH) to fix carbon and generate organic compounds (e.g. glucose).

Front 18

Chlorophyll

Back 18

Absorbs energy from the sun(in the blue and red range)and uses that energy to excite electrons, which it passes on.

Front 19

Rubisco

Back 19

Catalyzes the first step in the Calvin cycle

Front 20

Production of one Glucose molecule

Back 20

Requires six “turns” of the Calvin cycle, 6CO2, 18 ATP, and 12 NADPH.

Front 21

Asexual Reproduction

Back 21

one parent; offspring are identical to parent and to each other; variation comes about via mutation

Front 22

Who undergoes asexual reproduction?

Back 22

Prokaryotes, Single-celled eukaryotes (e.g. yeast, amoeba), and some higher eukaryotes (e.g. sea stars, many plants)

Front 23

Advantages of asexual reproduction?

Back 23

animals may be immobile; rapid spreading of a well adapted species (also carries risks in the face of rapid environmental change)

Front 24

Sexual Reproduction

Back 24

two parents; almost limitless diversity (although ultimately this diversity also derives from mutation); better able to survive rapid environmental change.

Fusion of two haploid gametes to form a diploid zygote

Front 25

What must reproduce by binary fission and why?

Back 25

Prokaryotes, because they lack a nucleus

Front 26

Mitosis in asexual and multicelluar Eukaryotes

Back 26

1. Reproduction, in asexual reproducing eukaryotes

2. Growth, development, tissue repair and replacement in multicellular eukaryotes.

Front 27

Meiosis

Back 27

Generation of gametes for sexual reproduction.

Front 28

Cell Cycle(in order)

Back 28

Interphase

(Mitosis)

Prophase

Metaphase

Anaphase

Telephase

Cytokinesis

Front 29

Parts of Interphase

Back 29

G1: Cytoplasmic components increase, cell size increases

S: DNA is replicated

G2: DNA repair

Front 30

Prophase

Back 30

1. DNA condenses so that chromosomes are visible in a light microscope

2. Nuclear envelope breaks down

3. Mitotic spindle begins to form

Front 31

Metaphase

Back 31

1. Chromosomes align along the middle of cell (Metaphase Plate)

2. Mitotic spindle fully formed

Front 32

Anaphase

Back 32

1. Sister chromatids separate

2. Migrate to opposite ends of thecell

Front 33

Telophase(and Cytokinesis)

Back 33

1. chromatin uncoils

2. new nuclear envelopes form

3. mitotic spindle disappears

4. cytokinesis

Front 34

Cytokinesis in Animals vs Plants

Back 34

Animals – a cleavage furrow forms and the cell pinches in two

Plants – a new cell wall forms between the two daughter cells

Front 35

The Result of Mitosis is...

Back 35

two genetically identical daughter cells.

Front 36

Checkpoints

Back 36

Cell cycle does not proceed by default (like dominoes); it will normally stop unless it receives a signal to proceed. An important checkpoint is in G1 and many growth factors work by overcoming this checkpoint.

Front 37

Cancer

Back 37

Escape from normal cell cycle control; uncontrolled growth is an important aspect of cancer.

Front 38

Tumor

Back 38

mass of transformed cells; leads to tissue damage (and death) by obstruction

Front 39

Malignant Tumor

Back 39

capable of traveling to and growing in a secondary site (metastasis) leading to a secondary tumor; most cancer death is due to secondary tumors

Front 40

Chemotherapy

Back 40

some forms of chemotherapy act by halting the cell cycle or attacking the mitotic spindle

Front 41

Humans have how many diploid and haploid chromosomes? What do each chromosome exist as?

Back 41

23 diploid and 46 haploid, as a homologous pair of one paternal and one maternal

Front 42

Tetrad

Back 42

pair of homologous chromosomes,each of which exists as a pair of sister chromatids, aligned during meiosis (a pair of pairs)

Front 43

Sexual Life Cycle

Back 43

Diploid>>Haploid(meiosis)>>Diploid(fertilization)

Front 44

Features of Meiosis

Back 44

1. Occurs only in reproductive organs.

2. Generates haploid cells (gametes) from diploid cells.

3. DNA replication followed by two rounds of cell division to produce four haploid gametes

Front 45

Meiosis in brief

Back 45

Interphase – DNA is replicated

Meiosis I – segregation of homologous pairs

Meiosis II – segregation of sister chromatids

Front 46

Prophase I(meiosis)

Back 46

chromosomes condense as in mitosis, but now homologous chromosomes come together to form a synapse comprising two pairs of sister chromatids called a tetrad. Crossing over occurs while the tetrads are together.

Front 47

Metaphase I(meiosis)

Back 47

chromosomes align along the metaphase plate; the spindle microtube distinguishes between pairs of sister chromatids in a tetrad so that itcan separate homologous pairs.

Front 48

Anaphase I(meiosis)

Back 48

migration of chromosomes toward the two poles of the cell. In contrast to mitosis however, sister chromatids remain associated; only tetrads come apart so homologous chromosomes migrate to opposite poles.

Front 49

Telophase I and Cytokinesis(meiosis)

Back 49

each pole of the cell has a haploid set of chromosomes (in duplicate form as sister chromatids); cytokinesis leads to two haploid daughter cells; meiosis II may immediately follow telophase I or there may be an interphase (without DNA replication).

Front 50

Meiosis II

Back 50

essentially the same as mitosis but starts with haploid cells resulting in four haploid daughter cells.

Front 51

Meiotic Recombination(crossing over)

Back 51

the exchange of corresponding segments between non-sister chromatids of homologous chromosomes. It happens during Prophase I and leads to the generation of recombinant chromosome and increases genetic diversity

Front 52

Nondisjunction

Back 52

failure of homologous chromosomes to separate during anaphase I or of sister chromatids to separate during anaphase II.

Front 53

Nondisjunction can lead to...

Back 53

one extra or one fewer chromosome, but loss of any chromosome except for Y is deadly to the developing embryo. Similarly, having an extra chromosome (trisomy) is also deadly to the embryo except X, Y, 13, 18, and 21.

Front 54

Karyotype

Back 54

ordered display of chromosomes; detects abnormalities in chromosome number.

Front 55

Mendels Laws

Back 55

1. Law of Segregation

2. Law of Independent Assortment

Front 56

Law of Segregation

Back 56

Genes exist in different versions (alleles),which accounts for variation in a character. An individual has two alleles for each gene,one from each parent, and can be homozygous or heterozygous.

Front 57

Law of Independent Assortment

Back 57

The alleles of a given gene segregate and the alleles of different genes segregate independently of one another.

Front 58

Variations of Mendel's Laws

Back 58

Environmental Effects

Polygenic Traits

Linkage

Incomplete Dominance

Codominance

Pleiotropy

Multiple Alleles

Front 59

Chromosomal Basis of Inheritance

Back 59

Genes occupy discreet loci (positions) on chromosomes and the behavior of chromosomes during meiosis and fertilization determines segregation and independent assortment.

Front 60

Transcription

Back 60

synthesis of RNA (mRNA, rRNA, tRNA) using DNA as a template.

Front 61

Translation

Back 61

synthesis of protein using mRNA as a template

Front 62

Messenger RNA

Back 62

encoded by genes, in turn it encodes protein; a triplet of nucleotides (called codons) encode on amino acid

Front 63

Transfer RNA (tRNA)

Back 63

covalently binds and “charges” amino acids; reads the genetic code through an anticodon

Front 64

Ribosomal RNA (rRNA)

Back 64

the RNA component of ribosomes

Front 65

Genotype and Phenotype

Back 65

Genotype: heritable information contained in nucleotide sequence

Phenotype: organism’s physical traits

Front 66

Codon

Back 66

a single amino acid is encoded by a triplet of nucleotides. One start codon and three stop Codons. Redundant but not ambiguous.

Front 67

Steps of Protein Synthesis

Back 67

Initiation

Elongation

Termination

Front 68

Gene=

Back 68

1. coding sequence (exons in eukaryotes)

2. introns (eukaryotes)

3. controlling elements.

Front 69

Blood Types

Back 69

A

B

AB

O

Front 70

Blood Type Alleles

Back 70

IA

IB

IAIB

ii

Front 71

operon

Back 71

cluster of genes under control of a common promoter