Bio/Biochem Review Flashcards
How do catalyts and inhibitors affect reaction rates?
How is ∆G affected by enzymes?
Catalysts increase the reaction rate, inhibitors decrease the reaction rate
∆G is not affected by enzymes
Name the cellular location and end products (per glucose) for the following:
Glycolysis, pyruvate dehydrogenase complex, Krebs cycle, electron transport, fermentation
Glycolysis: Cytoplasm, 2 NADH, 2 pyruvate, 2 ATP (net)
PDC: Mitochondrial matrix, 2 NADH, 2 acetyl-CoA and 2 CO2
Krebs Cycle: Mitochondrial matrix, 6 NADH, 2 FADH, 2 GTP, 4 CO2
Electron Transport Chain: Inner mitochondrial membrane, end product is a proton gradient (30 ATP generated)
Fermentation: Cytoplasm, end products are 2 ATP, 2 lactic acid (muscle) or 2 ethanol (yeast)
Name the cellular location and main products of the following biochemical pathways:
Gluconeogenesis, glycogenesis, glycogenolysis, fatty acid oxidation, fatty acid synthesis, and the pentose phosphate pathway
All reactions occur in the cytosol besides fatty acid oxidation, which occurs in the mitochondrial matrix
Gluconeogenesis - Glucose-6-phosphate
Glycogenesis - glycogen
Glycogenolysis - Glucose-1-phosphate
Fatty acid oxidation - Acetyl-CoA units
Fatty acid synthesis - 16-C fatty acid (palmitate)
Pentose phosphate pathway - NADPH (oxidative) ribulose-5-phosphate (non-oxidative)
Define replication, transcription, and translation. At which stage is protein synthesis primarily regulated?
Replication = DNA to DNA
Transcription = DNA to RNA
Translation = RNA into protein
Regulation of protein synthesis if primarily at the level of transcription.
What does semiconservative replication mean?
After DNA replication, one strand of a DNA double helix is composed of old DNA and the other is composed of newly-synthesized DNA
What are the differences between DNA and RNA?
Name 3 types of RNA and their functions
DNA is double stranded, thymine, sugar is deoxyribose
RNA is single stranded, uracil, sugar is ribose
mRNA = translated to make proteins
rRNA = needed to make a functional ribosome (Without, cell can’t make proteins, and cell function will be inhibited)
tRNA = carries an amino acid to a ribosome to be incorportated into a growing protein
Name at least 5 differences between prokaryotes and eukaryotes
Prokaryotes don’t have a nucleus or organelles, have a single circular chromosome, 3 different DNA polymerases and 1 RNA polymerase. Transcription and translation are simultaneous, their mRNA is polycistronic, and there is no mRNA processing
Eukaryotes have a nucleus and other organelles, have several linear chromosomes, 1 DNA polymerase and 3 different RNA polymerases. mRNA is monocistronic, and mRNA must be processed before translation.
What is the basic structure of a virus?
A virus is a piece of nucleic acid surrounded by a protein shell (capsid)
Viruses are obligate parasites
Name three different life cycles of a virus. Which of these is of an animal virus life cycle only?
Lytic, lysogenic, productive
Productive is for animal viruses only
What is a prion? What is a viroid?
A prion is an abnormally folded version of a normal protein that is able to convert other prions to its abnormal form. (Infectious protein)
They are highly resistant to degradation by heat, acids, etc and are implicated in degenerative brain disorders
Viroids are short, single stranded RNAs that have highly complimentary sequences. They are plant pathogens that are though to affect protein synthesis by binding and silencing normal cellular RNAs.
Name the 3 shapes of bacteria
Coccus (round)
Bacillus (Rod-shaped) (E. Coli is a gram negative bacillus)
Spiral (Spirochete)
Define obligate aerobe, facultative anaerobe, tolerant anaerobe, and obligate anaerobe
Obligate aerobe - must use oxygen to survive
Facultative anaerobe - prefers oxygen, but will ferment to survive
Tolerant anaerobe - can tolerate oxygen, but ferments to survive
Obligate anaerobe - will die in the presence of oxygen
Name the cell organelles and their functions
Nucleus = control center, contains DNA and is the site of replication and transcription
Ribosome = protein synthesis
Rough ER = holds ribosomes that are synthesizing secreted or membrane proteins, functions in protein modification
Golgi apparatus = sorts and packages proteins, protein modification
Lysosome = digestive enzyme container
Mitochondria = energy production
Smooth ER = lipid metabolism
Centrosome = mitotic spindle formation
Peroxisome = eliminated free radicals
What are the four main colligative properties?
What do they depend on?
Vapor-pressure depression, boiling point elevation, freezing-point depression, and osmotic pressure.
They depend only on the number of solute particles in a solution and not on the type of particle
What is the difference between osmosis and diffusion?
What is the van’t Hoff factor?
Osmosis is the movement of water from an area of low solute concentration to an area of high solute concentration
Diffusion is the movement of solute from an area of high solute concentration to an area of low solute concentration
The van’t Hoff factor is the ionizability factor, it tells how many ions one unit of substance will produce in solution
What types of molecules can easily cross the plasma membrane? Which cannot?
Small, nonpolar molecules can easily cross the plasma membrane (Oxygen, CO2)
Large, and/or polar molecules cannot
What is an oncogene?
What is a tumor supressor gene?
An oncogene is a mutated proto-oncogene that are permanately active.
Proto-oncogenes regulate the cell cycle, and activate it during times of development, growth, or healing.
The cell cycle is permanently on, and cell growth and division occurs without control. Gain of function mutation
Tumor suppressor genes code for proteins to slow or stop the cell cycle until DNA damage is repaired. If DNA is not repairable, they trigger apoptosis. Loss of function mutation
Name the stages of mitosis and describe the location of the chromosomes in each.
What is the end product of mitosis?
Where is there heavy regulation?
What is the difference between mitosis and meiosis?
Prophase = replicated chromosomes condense in a deteriorating nucleus (Build spindle, condense DNA, break down nuclear membrane)
Metaphase = chromosomes randomly align at the cell center
Anaphase = separate sister chromatids by pulling at the centromeres (Cytokinesis begins)
Telophase = Reverse prophase. Decondense DNA, break down the spindle, and rebuild the nuclear membrane. Finish cytokinesis
DNA replication occurs during the S phase of interphase
The end product of mitosis is two daughter cells that are identical to each other and identical to the parent cell
There is heavy regulation at the G1-S phase, because the cell isn’t going to replicate if it doesn’t need to.
Mitosis is the division of s**omatic (body) cells, meiosis is the division of gametes (germ cells)
Name the stages of meiosis and describe the location of the chromosomes in each.
When is the cell considered to be haploid?
What is the end result of meiosis?
Prophase I - Build spindle, condense DNA, break down nuclear membrane (Synapsis - pairing of homologous chromosomes/Crossing over occurs - DNA exchange) (Specific) *Longest phase of meiosis
Metaphase I - Tetrads randomly align at the cell center. (In mitosis it would be individual chromosomes)
Anaphase I - separate homologs partners, pulled to opposite sides of the cell. Begin cytokinesis
Telophase I - New nucleus forms. (Possibly reverse mitotic prophase)and finish cytokinesis
Prophase II, metaphase II, anaphase II, and telophase II = chromosome movements are identical to movements during mitosis, but the amount of DNA is reduced by half. (starting with less)
Cell is haploid after telophase I
Is diploid during G1 and G2
4 cells that are very different from each other and from the parent cell
Define gene, traitr, allele, genotype, and phenotype
Gene = piece of DNA that codes for some product
Trait = physical characteristic of an organism
Allele = version of a gene
Genotype = combination of alleles an organism has
Phenotype = physical characteristics of an organism dictates by alleles
State the rules of multiplication and addition.
How can they be used?
Rule of multiplication: probability of A and B = (Prob A) x (Prob B)
Rule of addition - Probability of A or B = (Prob A) + (Prob B) - (Prob A and B)
These are used to solve genetic probability problems by reducing them to a series of simple single gene crosses, the results of which can be combined using the rules.
What are the outcomes of the four basic single gene crosses?
- Homozygote x Homozygote = 100% same homozygote
- Homozygous dominant x homozygouse recessive = 100% heterozygote
- Homozygote x heterozygote = 50% same homozygote, 50% heterozygote
- Heterozygote x Heterozygote = 25% homozygous dominant, 50% heterozygotes + 25% homozygous recessive
Name two ways to determine whether genes are linked
If after a cross involving two different genes, the progeny do not match what would be expected ratios for unlinked genes. (The alleles don’t sort independently)
RF value < 50%
Recombination frequency = # recombinants/total progeny x 100
What are the two Hardy Weinberg equations?
What are the 5 conditions for these equations
Allele frequency: p + q = 1
Genotype frequency: p2 + 2pq + q2 = 1
Large population, random mating, no migration, no mutations, no natural selection