Cellular respiration intro

Question 1

define: cellular resp

Answer 1

process which transfers the chemical energy stored in glucose to the chemical energy in ATP

Question 2

additional purpose of celular respiration?

Answer 2

to provide energy for endergonic processes which are vital to life eg. homeostatic mechanisms, protein and DNA synthesis, active and bulk transport

Question 3

does cellular resp occur in all living things all the tim?

Answer 3

yes?

Question 4

why is atp the usable form of energy

Answer 4

bc its energy can be released in a single step

Question 5

equation?

Answer 5

30ADP + 30Pi –> 30ATP

C6H12O6 + 6O2  6CO2 + 6H2O

Question 6

mitochondria strcuture?

Answer 6

• Outer membrane, and highly folded inner membrane (folds called cristae, which serve to increase the SA of the inner membrane)
• The matrix is the liquid inner space.

Question 7

describe endosymboitic origins of mitochondria

Answer 7

• A free-living microbial cell which was capable of aerobic respiration (ie. the original mitochondria) was, ages ago, engulfed by another microbial cell. This event soon gave rise to the first aerobic eukaryotes.
o The engulfed cell gained a protective environment
o The host cell gained a more efficient source of ATP (previously anaerobic only).

Question 8

evidence for bacterial origins of mitochondria?

Answer 8

o Mitochondria have similar lengths to bacteria cells
o Mitochondria have a double membrane, similar to the double membrane of the outer and inner membranes of cell walls.
o DNA:
 Mitochondrial has circular DNA molecule, like in bacterial cells.
 Mitochondrial DNA replicates independently of host DNA
o Mitochondria divide by binary fission, like bacteria.
o Mitochondria have their own ribosomes of a similar size to bacterial cells. Eukaroytic ribosomes are bigger.
o Mitochondrial outer membrane contains porins that are transmembrane protein channels, similar in structure to bacterial porins.

Question 9

effect of temp?

Answer 9

all stages have enzymes…

Question 10

effect of oxygen and glucose concentration/availability

Answer 10

both inputs. one of electron transport chain, the other of glycolysis.
as they increase, ROR increases to a point but there will be a limiting factor - enzymes fully occupied, or coenzymes at full capacity.