Lipid and Amino Acid Metabolism

Question 1

why do we need energy?

Answer 1

Synthesis & maintenance of their own structures.
-in growth, or in repair after injury.
Performance of mechanical work.
-muscle contraction
Active transport of substances into & out of cells
-import of food molecules from gut into cells – “digestion”

Question 2

where is the energy derived for theses processes

Answer 2

light- phototrophs
chemicals (food)- chemotrophs

Question 3

Processes that release energy are what?

Answer 3

favoured

Question 4

Processes that require energy are what?

Answer 4

not favoured

Question 4

why is energy required

Answer 4

overcome the forces preventing movement of the body (gravity, air resistance, friction etc).

Question 4

how is energy released?

Answer 4

energy release from Glucose

Question 5

what does food usually contain?

Answer 5

carbon-containing compounds

Question 6

the oxidiaton of glucose results in?

Answer 6

Breakdown of “carbon skeleton” of glucose molecule
Combination of carbons with oxygen to form carbon dioxide.
Formation of water from remaining hydrogens and oxygens.

Question 7

the breakdown of glucose produces how much energy?

Answer 7

16000 J per gram of glucose

Question 8

energy derived from food is converted into what?

Answer 8

ATP.

Question 9

describe atp

Answer 9

principal donor of energy to Biological Systems
energy-rich molecule due to its 3 phosphate groups – ‘triphosphate

Question 10

why is atp described as “cash in hand”

Answer 10

readily ‘top-upable’; ATP & its lower-energy form ADP are readily interconvertible; reaction catalysed by Adenylate Kinase

Question 11

what is the atp and adp cycle

Answer 11

biological process that cells use to store and release energy.

Question 12

why is the adp and adp cycle continous?

Answer 12

cells constantly use and regenerate ATP. Enzymes called ATPases are involved in the hydrolysis of ATP, and other enzymes like ATP synthase help in the synthesis of ATP.

Question 13

describe metabolsim

Answer 13

catabolism and anabolsim

Question 14

what is substrate level phosphorylation

Answer 14

Direct Transfer of phosphate gp from metabolites to ADP - producing ATP.

Question 15

the generation of atp in glycolysis is what?

Answer 15

anerboic

Question 16

what is Oxidative phosphorylation

Answer 16

atp formed INDIRECTLY from oxidation of carbon atoms in fuel molecules (carbohydrate, fat, amino acids)

Question 17

what % of atp is formed in oxidative phosphorylation

Answer 17

90%

Question 18

what is the main purpose of mitochondria

Answer 18

Organelles that generate ATP (via oxidative phosphorylation) for cellular use

Question 19

where is mitchondira mainly present

Answer 19

larger numbers where lots of energy is required (eg. cardiac muscle cells, sperm flagella)

Question 20

describe the structure of mitchondria

Answer 20

Surrounded by a double-membrane system
Outer membrane.
Inner membrane.
Intermembrane space
Interior (matrix)

Question 21

what is the role of mitochondrial reactions in metabolsim

Answer 21

Oxidative decarboxylation

Question 22

Oxidative decarboxylation ?

Answer 22

oxidation + loss of C atoms

Question 23

where does the etc get energy release from?

Answer 23

energy release from oxidation to energy-requiring H+ pumping across inner membrane into intermembrane space

Question 24

how does atp synthase produce energy in oxidiative phosphyrlation?

Answer 24

H+ escape across inner membrane to energy-requiring ATP synth.
[3x H+  synth of 1x ATP]

Question 25

because of intergrated metabolsim what can cells also depend on?

Answer 25

other carbohydrates, including glycogen
fats
proteins/amino acids

Question 26

what is a ‘junction point’

Answer 26

molecules or metabolic stages that play a pivotal role in the regulation of metabolic pathways