AOS 1 Flashcards
(24 cards)
What are 5 pieces of evidence supporting the bacterial origins of chloroplasts and mitochondria?
- They have their own DNA, which is circular.
- They have their own ribosomes and produce their own proteins.
- They reproduce by binary fission independently of cell cycle.
- They are bound by a double plasma-membrane.
- They have porin transport proteins only found in prokaryotic plasma membranes.
How are glucose/carbohydrates stored in plant cells? (2)
As starch in plant cell amyloplasts.
As cellulose in plant cell wall.
How are glucose/carbohydrates stored in animal cells?
As glycogen in liver and muscle cells.
What bonds join amino acids, what reaction, what molecule is produced?
Peptide bonds join amino acids in a condensation reaction (produces water molecule) which produces a polypeptide (protein).
Describe the amino acid structure.
Amino group (H2N), Carbon atom, Carboxyl group (COOH), Hydrogen atom, R chain
Describe the four protein orders and bonds.
Primary: linear sequence of amino acids (peptide bonds).
Secondary: folding to alpha-helix or beta-pleated (hydrogen bond).
Tertiary: irregular folding (hydrogen and ionic bonds).
Quaternary: 2 or more tertiary chains.
List 5 factors that affect diffusion
Size of molecule, polarity, charge, amount, concentration gradient.
List 5 functions of the plasma membrane
Protects cell Contains contents Cell identity Communication Controls movement of substances
Describe the structure of a phospholipid
Polar head: glycerol backbone & phosphate group
Non-polar tails: 2x fatty acid chains (one sat, one un-sat)
Identify RNA/DNA in a nucleotide
(bottom of pentagon)
2x OH groups = RNA
1x OH 1x H = DNA
What is the difference between the two types of inhibitors?
Competitive: competes for active site
Non-competitive: alters active site shape
What is a coenzyme?
An organic (molecule) that allows enzyme to function, usually by carrying an electron/ion (eg. ATP/NADPH).
What is a cofactor?
Inorganic (ion) that allows enzyme to function.
What is activation energy?
The energy required to break the bonds in the reactants of a reaction so the reaction can begin.
How do enzymes affect activation energy?
They lower Ea
Describe a condensation reaction
A reaction that releases water molecules (eg. polymerisation, anabolic (absorbs energy) (THINK PHOTOSYNTHESIS)
Describe a hydrolysis reaction
Reaction that requires water, catabolic (releases energy) (THINK CELLULAR RESPIRATION)
Describe the overall equation for photosynthesis
CO2 + H2O -> (Chlorophyll & light) O2 & C6H12O6
Describe the first stage of photosynthesis
Light dependent
In thylakoid membrane of chloroplast
Chlorophyll absorbs light energy (enzymes)
H2O is split by light into H+ and O2, forms ATP
H+ joins to NADPH
Oxygen is waste product
Describe the second stage of photosynthesis
Light independent/Calvin cycle
In stroma of chloroplast (liquid)
NADPH and ATP and CO2 are joined together by RuBisCo to form glucose
What is the point where the rate of ps and res are equal?
Compensation point (no net increase/decrease of CO2)
Describe the first stage of respiration
Glycolysis
In cytoplasm
Anaerobic
glucose split into pyruvate and 2ATP and 2NADH
How much ATP is produced from respiration
36 or 38
Describe the second stage of respiration
Krebs cycle
In matrix of mitochondria (fluid)
Pyruvate is oxidised to Acetyl CoA
Acetyl CoA is split into 6CO2, 2ATP, 6NADH, 2FADH2
