Chemical Comp of Organisms
This type of bond involves the sharing of electrons. In addition, explain the meaning of polar vs. nonpolar of these bonds.
What is a covalent bond?
Polar: sharing of electrons is unequal, creates a partial charge
Nonpolar: equal sharing
This organelle manufactures proteins using instructions from DNA, and is itself made of RNA and proteins.
What are ribosomes?
This part of the enzyme physically interacts with the substrate, forming a “hand-in-glove” complex that allows the reaction to occur.
What is the active site?
This molecule is the main energy currency of cells, produced during cellular respiration and used whenever energy is needed.
What is ATP?
These two scientists published the double-helix model of DNA in 1953, showing that A-T and C-G bonds are the same length.
Who are James Watson and Francis Crick?
This type of chemical substance dissolves in water and decreases the concentration of hydrogen ions in the solution.
What is a base?
This organelle receives products from the ER, modifies them, and then sends them to their final destinations, acting as the cell’s “shipping center.”
What is the Golgi Apparatus?
Some enzymes cannot function without these helper molecules, which bind to the active site and assist in forming the enzyme-substrate complex. They can be permanent or detachable.
What are cofactors?
This first step in all organisms’ energy transformations splits glucose into two pyruvate molecules and produces a net of 2 ATP, whether oxygen is present or not.
What is glycolysis?
This enzyme unwinds the double helix during DNA replication by breaking the hydrogen bonds between nucleotides.
What is helicase?
Name the type of biological molecule whose monomers are called monosaccharides and whose polymers are called polysaccharide. Also, name an example of each.
What is a carbohydrate? The example of monosaccharide is glucose. The example of polysaccharide is starch.
This type of transport moves substances against their concentration gradient and requires both energy and membrane “doorway” proteins.
What is active transport?
This term describes the nonfunctional state of an enzyme caused by environmental changes such as temperature or pH altering the shape of its active site.
What is denaturation?
This process occurs in the mitochondria, converts pyruvate into acetyl CoA, and feeds molecules into the citric acid cycle during aerobic respiration.
What is pyruvate oxidation?
During translation, this type of RNA carries amino acids from the cytoplasm to the ribosome and matches anticodons to codons.
What is tRNA (transfer RNA)
These molecules store biological information and are made of monomers containing one nitrogen base, one sugar, and one phosphate group. Name the molecules, both possible sugars, AND all possible nitrogenous bases.
What are nucleic acids? Their sugars are ribose (RNA) and deoxyribose (DNA). The possible nitrogenous bases are adenine (A), thymine (T, DNA only), uracil (U, RNA only), cytosine (C), and guanine (G).
Before a cell divides, each chromosome is copied, producing two identical structures held together at a centromere. During division, these structures separate. Name these identical structures, and identify the protein complex they are wrapped around before condensing into visible chromosomes.
What are sister chromatids, and they are wrapped around histones?
These molecules interfere with enzyme activity either by occupying the active site themselves or by binding elsewhere and altering the active site’s shape.
What are inhibitors?
When oxygen is absent, pyruvate undergoes this type of conversion, producing either lactic acid or ethanol and yielding very little ATP.
What is anaerobic respiration (lactic acid or alcoholic fermentation)?
Mutations can be caused by accidents during replication or exposure to carcinogens. Name the two main types described in your notes.
What is the first law of thermodynamics? Also, explain the meaning of exothermic and endothermic reactions in this context.
What is 'energy cannot be created nor destroyed'. Exothermic reactions release energy, endothermic reactions take in energy, but they both involve energy being transferred.
This specific phase of the cell cycle involves DNA existing as unwound chromatin, DNA replication occurring, and the cell preparing for division—even though no actual division occurs. Name the entire stage and its three sub-phases.
What is interphase? The three phases are G1, S, and G2.
Some enzymes require additional molecules to function properly. These helper molecules can be inorganic metals or organic vitamins. Name the two types of cofactors, and give an example of each.
What are inorganic cofactors (metal ions, Fe2+) and organic cofactors (vitamins, B6)?
Photosynthesis has two main stages. Name the stage that occurs in the thylakoid membranes, captures light energy, produces ATP, and releases oxygen, and the stage that occurs in the stroma, uses ATP and CO₂, and produces glucose.
What is light reactions?
What is dark reactions?
Bacteria can acquire new genes through external DNA or viral transfer. Name the process where a virus transfers genes between bacteria, and the process where bacteria incorporate DNA from their environment.
What are transduction and transformation?