Biology Test 3
Terms in this set (105)
LOSS of electrons
ADDING or GAIN of electrons
An electron transfer requires..
An electron donor and acceptor
Na- + Cl --> Na+ + Cl-
Na becomes oxidized, Cl becomes reduced.
NAD+ is an
NADH is NAD+ in its..
Most of the electrons removed from food are transferred to NAD+, making
a NUCLEOTIDE is make up of 3 parts:
A pentose, nitrogenous base, and triphosphate group
3 Stages of Cellular Respiration:
Glycolysis, pyruvate oxidation & citric acid cycle, (CAC) and Oxidative Phosphorylation
The energy output in glycolysis, net gain of?
Pyruvate is broken down into..
The cycle generates _____ per turn by ______________
Most of the chemical energy is transferred to ________, during redox reactions.
3 CO2 molecules
1 ATP per turn by substrate lvl phosphorylation
NAD+ and FAD during redox reactions
Does the electron transport chain make any ATP?
It makes NO ATP directly
Chimiosmosis couples electron transport to ____________
Chemiosmosis: ATP synthesis powered by flow of _____ back across the membrane
ETC: Elec transport & pumping of protons create an ________ across the membrane.
ATP yield her molecule of glucose:
Pyruvate ox. & CAC ______
Oxidative Phos. _______
26 or 28 ATP
When there is no _________ cells use fermentation to make ________ by substrate lvl phosphorylation.
make ATP by substrate lvl phosphorylation
Pyruvate serve as an ________________ for oxidizing _______ back to ______.
2 common end products:
electron ACCEPTOR for oxidizing NADH back to NAD+
Ethanol and lactate
What process is common in BOTH fermentation and cellular respiration?
Why's it difficult to burn fat?
Requires more energy; a gram of fat oxidized by respiration makes 2 MORE that twice as much ATP as a gram of carb.
End product of anabolic pathway inhibits the enzyme that catalyzed an early step of pathway
CHPT 12: MITOSIS
division of 1 nucleus into 2 genetically identical nuclei
A genome is..
cell's endowment of DNA
Somatic cells are..
all body cells except sex cells. human 46-chrs
Sex cells. Human egg and sperm- 23 chrs
Sister chromatids are..
joined copies of one orig. chromosome
protein complexes attached on walls of sisters
region of chromosomal DNA where chromatid is attached to sister
Division of cytoplasm
THE CELL CYCLE: INTERPHASE
90% of cell cycle, 3 sub phases, G, S, and G2 phases
Mitosis has 5 stages. List them:
Prophase, prometaphase, metaphase, anaphase, telophase
Cytokinesis _________ the cell and makes ______________ cells.
divides the cell and makes 2 daughter cells
Nuclear envelope encloses nucleus
2 centrosomes form by duplication
Chromatin fibers tightly coil
Mitotic spindle forms
Centrosomes move away from eachother
Nuclear envelope fragments
Microtubules INVADE nuclear are
Centrosomes are now on OPPOSITE sides of cell
Chromosome arrive at metaphase plate
Shortest stage, last a few min
Begins when cohesion proteins are cleaved, 2 sisters part suddenly
2 free daughter cells move to opposite sides of cell
2 ends of cell now have 2 equal sets of chromosomes
In CYTOKINESIS, the cleavage that splits the cell:
In animal cells, its called __________________
In plant cells, its called ___________________
Animal cells- cleavage furrow
Plant cells - cell plate
Division in half
Asexual rep. of single celled eukaryotes
3 cell cycle checkpoints:
G1, G2, M
Cells in culture that get ability to divide indefinitely
What is a BENIGN tumor?
Abnormal cells that stay at original site
What is a MALIGNANT tumor?
Cell that are able to spread to new tissue, and impair organ functions
What is metastasis?
Spread of cancer cells to locations far from their original site
CHPT 13: MEIOSIS
Nucleosomes are also known as..
"beads on a string"
Describe the structure of a nucleosome:
Protein core of 8 HISTONES (2 of each H2A, H2B, H3, H4) & DNA wound 2x around protein core.
How long is a nucleosome?
10 nm fiber
Karyotyping patterns are generated from what type of cells in metaphase?
Names of 3 DNA Replication models?
conservative, semiconservative, dispersive models
Origin of replication:
In bacterial cells, __________ origin(s)
In eukaryotic cells, ________ origin(s)
Bacterial cells- 1 origin
Eukaryotic cells- multiple origins
SYNTHESIS OF STRAND DURING DNA REPLICATION
The RNA primer:
synthesizes the primers, using DNA as template
UNWINDS & SEPARATES the DNA
The single strand binding proteins:
STABILIZE the unwound strands
BREAKS, SWIVELS, & REJOINS the DNA
1. The primase:
joins RNA nucleotides into a primer
2. DNA pol III add ______________ to primer, forming _____________________.
add DNA nucleotides to primer, forming Okazaki fragment 1
3. After reaching next RNA primer to the right, DNA pol III __________________.
DNA pol III DETACHES.
4. Fragment 2 is ___________.
Fragment 2 is PRIMED
5. DNA pol I replaces _____ with _____.
Replaces RNA with DNA
6. DNA ligase forms bond b/w _________ and _______________.
forms bond b/w NEWEST DNA and FRAGMENT 1 DNA
7. Lagging strand is _________
They consist of:
Many repetitions of one short nucleotide sequence
Telomeres have 2 protective functions:
PREVENT DETERIORATION of chromosomes during cell division & repair
PREVENT FUSION to neighbor telomere
An oncogene is a..
Cancer causing genes
Normal versions of cellular genes, codes for proteins
Homologous chromosomes are:
2 chrom. of a pair have same LENGTH, CENTROMERE POSITION, & STAIN PATTERN
Sex chromosomes are:
chrom. that determines one's sex
chrom. other than sex chrom.
A DIPLOID cell has:
2 sets of chrom.
A HAPLOID cell has:
1 set of chrom.
Meiosis INTERPHASE summary of steps:
1. pair of homologous chromos in diploid parents cell 11
2. pair of duplicated homo chromos 11 11
(sister chromatids)- diploid cell w duplicated chromos
Meiosis 1 summary of steps:
1.pair of homo chromos in diploid parent cell 1 1
2.pair of duplicated homo chromos 11 11
3. homo chromos separate (haploid cells w duplicated chromos) becomes 2 cells each with one x in it
( separating the xx to two separate x x )
Meiosis 2 summary (end of meiosis 1 leading into meiosis 2)
following homo chromos separating ...
2.sister chromatids literally separate
x x becomes 1 1 1 1 (physically separates the sister chromatids)
Comparison of Mitosis and Meiosis chart summary
MITOSIS DNA replication: occurs in interphase before mitosis begins
# of divisions: 1, including all phases.
Synapsis of homo chromosomes: does NOT occur
2 DAUGHTER CELLS, each genetically identical to the parent cell, w/ same # of chromos.
role in animal/plant body: allows multicellular gameotphyte or sprophyte to arise from a single cell; makes cells for growth repair and in some species, asexual reproduction. Makes gametes in gametophyte plant.
Comparison of Mitosis and Meiosis chart summary
MEIOSIS DNA replication: occurs in interphase before meiosis 1 begins
2 DIVISIONS, each including all phases
Synapsis of homo chromos: Occurs during P1 along w crossing over b/w non sister chromatids, resulting CHIASMATA holds pairs together due to sister chromatid cohesion.
4 DAUGHTER CELLS, each haploid N, genetically diff from the parent cell & from each other.
Role in animal or plant body: Makes gametes in animals or spores in plants. Reduces # of chromo sets by HALF and introduces genetic variability among gametes or spores.
MEOISIS: Prophase 1:
DNA condenses to form chrom, sister chromatids join together at centromere, crossing over happens. ***AFTER CROSSING OVER HAPPENS, the 2 sister chromatids are no longer identical.
Chrom align at the equator of cell.
Homo. chrom. separate and go to opposite sides of cell. Sister chromatids remain attached at centromeres.
TELOPHASE 1 AND CYTOKINESIS
Cell divided into 2 daughter cells, nuclei reappears and forms around the cells. Cells prepare for Meiosis 2
MEOSIS II PROPHASE II
Nuclear envelope breaks down, spindle apparatus forms. Crossing over does NOT OCCUR.
Chrom. align randomly at the equator of cell.
Sister chromatids are pulled apart, centromere is broken.
TELOPHASE II & CYTOKINESIS:
Nuclear membrane reforms, cytoplasm divides into 2 haploid daughter cells, with a total of four unique haploid cells.
CHPT 16: MOLECULAR GENETICS
Change in GENOTYPE & PHENOTYPE bc of assimilation of external DNA by a cell
Frederick Griffith studied:
2 strains of the bacterium Streptococcus pneumonae.
Which strain can cause pneumonia in mice?
The smooth (S) strain
Why is it pathogenic?
Bc the cells have an OUTER CAPSULE that protects it from the animal's immune system
Cells of the rough (R) strain lack a __________, and therefore are nonpathogenic.
Rough strain cells lack a CAPSULE
What are phages/bacteriophages and what are they mostly made of?
Viruses that infect bacteria virus; They are composed mostly of DNA and protein
They used ______________ to trace the fates of _____________ of T2 phages that infected bacteria cells.
They used RADIOACTIVE SULFUR AND PHOSPHORUS to trace the fates of DNA AND PROTEIN of T2 phages that infected bacteria cells
What did they want to see?
What did they do?
Which molecule entered the cells and could reprogram them to make more phages
Mixed radioactively loaded phages w/ bacteria
Agitated mixture in a blender to free phage parts outside the bacteria from the cells
Centrifuged mixture so bacteria formed a PELLET at bottom of test tube
Measured radioactivity in the pellet & liquid
PHAGE DNA entered bacteria cells, PHAGE PROTEINS DID NOT.
Sea Urchins have the most _______ and the least ________
Ox had the least _______ and the most ____________.
The most ADENINE and the least GUANINE.
The least ADENINE and the most GUANINE.
For each species, the % of ___________ bases are roughly equal and the % of _________ are roughly equal.
the % of A & T bases are roughly equal and the % of G & C are roughly equal.
Rosalind Franklin'd contribution to discovery of DNA double helix model:
Who proposed the model of DNA?
Her X-ray diffraction photo of DNA
Watson and Crick
Base Pairing in DNA:
Purine + purine = ?
Pyrimidine + pyrimidine = ?
Purin + pyrimidine = ?
Purine + purine = TOO WIDE
Pyrimidine + pyrimidine = TOO NARROW
Purin + pyrimidine = Width consistent / X-ray data
Pairs of nitrogenous bases in DNA double-helix are held together by _____________.
Beauty of double helix model?
The structure of DNA suggested the basic mechanism of its replication