Exam 2: Perpetuation of Life Flashcards
Parts of a nucleotide (Monomer of DNA/RNA)
Phosphate group
5 carbon sugar
Nitrogenous base
Pyrimidines vs Purines
Pyrimidines(smaller):
Cytosine, Uracil, Thymine
Purines(larger): Adenine, Guanine
How do the nitrogenous bases pair
Purine across from Pyrimidine (hydrogen bonds)
(Purine-Purine theres not enough space)
(Pyr-Pyr theres too much space)
How does the addition of a phosphate group to a nucleotide change it
Raises the potential energy of the monomer
Distance between each nucleotide step
0.34 nanometers
How many nucleotide steps in a helix
10
Distance between the two helixes
2 nanometers
When was the Watson+Crick Model
1953
Conservative model
Old - Old
Old- Old New - New
Total length of strand
3.4 nanometers
3 Potential Models of DNA Replication
- Conservative
- Semi-Conservative
- Dispersive
Semi-Conservative Model
Old- Old
Old-New Old-New
Dispersive model
Old-Old
Mix-Mix Mix-Mix
Not accurate- information is too important to scramble
When was Meselson+Stahl
1958
Meselson+Stahl
Nitrogen seperates differently in sedimentation gel based on weight
What is Mitosis
Cell division for growth, development, and repair
Two parts of a chromosome
- Telomeres- ends of chromosome
- Centromere- center of chromosome
What is Meiosis
Cell division for reproduction of gametes
How does the amount of chromosomes change from parent to daughter cells in Mitosis vs. Meiosis
Mitosis: 2 daughter cells, Amount stays the same
Meiosis: 4 daughter cells, each has half as many chromosomes as parent
G1, S, G2
G1: Make sure there is enough nucleotides
S: DNA Synthesis (nucleotides form DNA)
G2: Make sure all chromosomes are copied
Then, mitosis
Interphase
Starting point before either mitosis or meiosis
Sister chromatids
Prophase
-Nuclear Membrane disassembled
-Spindle fibers form at opposite ends of cell and try to attach to sister chromatids
-Once both fibers hook onto all chromatids, the play tug o war
When do the chromatids line up single vs double file
Mitosis: Single file
Meiosis Phase I: Double File
Meiosis II: Single file
Metaphase
-Sister Chromatids line up
Anaphase
-Sister chromatids separate from theyre duplicate
Telophase
- two nuclei form around each set
-Cell membrane pinches in center
Cytokinesis
-Contractile ring pinches completely and results in daughter cells
How do gametes know to undergo meiosis instead of mitosis
Sex cells receive testosterone/estrogen from the reproductive system
Lysosomes
Break down unwanted material in the cell using digestive enzymes (animals, plants)
Number of chromosomes in meiosis depending on series
At the end of series I, each cell has half as many as the parent cell in prophase I, still with 2 chromatids per chromosome
At the end of series II, each cell still has half as many as the parent cell in prophase I, but each chromosome has only 1 chromatid
Rough ER
Has ribosomes, involved in protein synthesis
Mitochondria
Powerhouse of the cell produces ATP (Animal, plant)
Ribosomes
Needed for translation (RNA-> protein)
Smooth ER
Involved in lipid synthesis
Golgi
Receives proteins and lipids from ER, and tells them where to go
Cell Wall
Provides structure and protection; made of cellulose (plants)
Chloroplasts
Plants: convert solar energy into glucose (photosynthesis)
Which is bigger: Eukaryotes or prokaryotes
Eukaryotes; need much more energy
Organelles in bacteria
DNA and ribosomes
Genotype vs Phenotype
Genotype: Genetic makeup
Phenotype: Visible traits
Self-pollenation
Plant has both female and male organs
Cross-Pollenation
Collect pollen from one individual and transfer to female organs of an individual whos male organs are removed
Alleles
Different versions of the same genes
Autosomes
Expressed the same in male and female
Humans have 44
Carriers
Carry a receccsive gene but do not portray it
Almost always maternal
3 prime end
Ends with OH group
5 prime end
ends with phosphate group
During polymerization, which end are new nucleotides added to
3 prime end
