Life/Molecules
What are the four classes of organic molecules?
Proteins, nucleic acids, carbohydrates, lipids.
What is the Central Dogma of Biology
DNA --> RNA --> Proteins
Replication, Transcription, Translation
What are the three parts of the cell theory?
1) All organisms are made of one or more cells 2) Cells are the basic building blocks of life
3) All cells come from existing cells
Where does photosynthesis occur?
Chloroplasts in cells.
What are the 4 types of cell signaling?
All cells have what three same characteristics?
1) Nucleic acids
2) Membranes that define cells and compartments within cells
3) Metabolism
What is the template and molecule that is created from DNA replication, transcription and translation?
Replication - template: DNA molecule:DNA
Transcription - template:DNA molecule: RNA
Translation - template:mRNA molecule:proteins
Where can ribosomes be found?
Free in the cytoplasm or bound to the ER.
Where does glycolysis, acetyl-CoA synthesis and the citric acid cycle occur?
Cytosol, mitochondrial matrix, and mitochondrial matrix.
True or False:
In GPCR signaling, the receptor is mobile in the membrane, whereas the G protein is fixed in the membrane.
False.
GPCR signaling, the receptor is fixed
G protein is mobile
Why is water a good solvent?
1. Good solvent because it’s polar
2. It’s polarity makes it unattractive to some molecules (hydrophobic ones) creating a way to isolate sections of the environment from each other
3. Hydrogen bonds make it do weird things, like float when it is frozen
4. Hydrogen bonds create surface tension
5. Hydrogen bonds make water a good insulator
What is polyadenylation and its purpose?
The addition of ~250 "A" nucleotides to the end of mRNA. Its purpose is to stabilize mRNA and help export it out of the nucleus.
Substrate and the reaction that they catalyze.
Of the 3 pathways (glycolysis, acetyl-CoA synthesis and the citric acid cycle), which pathway produces the most ATP?
Citric acid cycle (20) - substrate level phosphorylation (2) and oxidative phosphorylation (18)
Glycolysis (7) - substrate level phosphorylation (2) and oxidative phosphorylation (5)
Acetyl-CoA synthesis (5) - substrate level phosphorylation (0) and oxidative phosphorylation (5)
What are the three main components of the cytoskeleton? (in increasing size)
Microfilaments, intermediate filaments, microtubules.
What is the difference between saturated and unsaturated fatty acids?
Saturated: no double bonds, higher melting points, high intermolecular forces (van der waals)
Unsaturated: double bonds, lower melting points, lower intermolecular forces
How is initiation different in prokaryotes vs eukaryotes?
Prokaryotes:
-Translation is initiated at Shine-Dalgarno sequences, 5'-AGGAGGU-3'
-Many Shine-Dalgarno sequences per mRNA, sites of initiation per mRNA
Eukaryotes:
-Translation is initiated at 5' cap
-One 5'cap per mRNA, one site of initiation per mRNA
Does cholesterol increase or decrease membrane fluidity?
Low temperatures - increase
High temperatures - decrease
Of the 3 pathways (glycolysis, acetyl-CoA synthesis and the citric acid cycle), which pathway does not produce NADH?
All 3 pathways produce NADH.
Advantages and disadvantages of multicellularity (3 each)?
Advantages:
-Larger organisms tend to be predator rather than prey
-Large organisms are bale to move more quickly/control movement
-Larger organisms are better able to influence their environment
-Larger organisms are better able to maintain homeostasis
-Multicellular organisms can have cells with specialized functions
-Multicellular organisms operate more efficiently
-Multicellular organisms have a wider variety of structures and therefore a wider variety of functions
-Multicellular organisms can adhere to environment and still have other functions
Disadvantages:
-Requires hollow structure or buried cells
-Requires bulk transport system
-Requires more structures and genes for regulation
-Requires more structures and genes for adhesion
-Requires more structures and genes for communication
-Reproduction usually occurs only through small subset of cells.
Name the four classes of organic molecules, its functions, building blocks and that bond it makes.
Proteins - structure, catalysts for reactions - amino acids - peptide bone
Nucleic acids - encode genetic information - nucleotides - phosphodiester bonds
Lipids - energy storage, signaling, structure - N/A - N/A
Carbohydrates - energy storage, cell structure - monosaccharides, glycosidic bonds
What would happen if we did not have telomeres and telomerase?
Lagging strand would be short and it would lead to a series of shorter DNA strands. This would be harmful in cells that replicate DNA frequently, such as skin cells.
Feedback inhibition. A cell would do this as a regulatory mechanism.
What is photorespiration? Is it more efficient?
Respiratory process in higher plants where they take up oxygen in the light and give out carbon dioxide. No, it decreases efficiency.
Number of chromosomes upon completion of each stage in mitosis, meiosis I and meiosis II.
Mitosis: Prophase, Prometaphase, Metaphase (46)
Anaphase (92)
Telophase (92), 46 in each nucleus
Meiosis I: Prophase I, Prometaphase I, Metaphase I, Anaphase I (46)
Telophase I - (46), 23 in each nucleus.
Meiosis II: Prophase II, Prometaphase II, Metaphase II (23)
Anaphase II - (46)
Telophase II - (46) - 23 in each nucleus