Structure And Functions In Living Organisms

Question 1

(2.10) What are enzymes and what are their role as biological catalysts in metabolic reactions

Answer 1

-Enzymes are proteins that are biological catalysts
-They increase the ROR by providing alternative pathways and they lower the activation energy required
-they reduce the need for high temperatures to carry out reactions
-they bind with complimentary substrates and remain unchanged

Question 2

(2.11)affect of temperature on enzymes and their function

Answer 2

-Increased temp
-increased kinetic energy
-particles move faster and collide more frequently
-increases the number of successful collisions that exceed the required activation energy
-once the temperature exceeds optimum temperature the enzymes denature
-meaning sub rate no longer fits the shape of the active site as it has changed shape

Question 3

(2.12) PRACTICAL- investigate how enzyme activity can be affected by changes in temperature

Question 4

(2.13)Affect of PH on enzymes and their function

Answer 4

-interferes with the bonds holding the enzyme together
-it changes the shape of the active site and denatures the enzyme
-different enzymes have different optimum PH

Question 5

(2.14B)PRACTICAL-investigate how enzyme activity can be affected by changes in PH

Question 6

(2.15) define diffusion

Answer 6

The net movement of substances from an area of high concentration to an area of low concentration(down a concentration gradient) across a partially permeable membrane
THIS IS A PASSIVE PROCESS ( DOESN’T REQUIRE ENERGY )

Question 7

(2.1)Level of organisation(smallest to biggest)

Answer 7

-organelle
-cell
-tissue
-organ
-organ system
-organism

Question 8

(2.2) role of nucleus

Answer 8

-controls activity of the cell (by making proteins)
-contains chromosomes(stands of dna which carries the genes-each gene codes for a protein)

Question 9

(2.2)role of cell membrane

Answer 9

Controls what substances enter and leave the cell (selectively permeable)

Question 10

(2.2)role of cytoplasm

Answer 10

Where chemical reactions occur (contain catalysing enzymes)

Question 11

(2.2)role of mitochondria

Answer 11

-Site of aerobic respiration
-produces ATP

Question 12

(2.2)role of ribosomes

Answer 12

Where protein synthesis occurs

Question 13

(2.2)role of chloroplasts

Answer 13

-contains chlorophyll which absorbs light
-this light is used for photosynthesis
-which makes biological molecules for the cell

Question 14

(2.2)role of cell wall

Answer 14

-Helps keep shape of the cell
-keeps plants upright

Question 15

(2.2)role of vacuole

Answer 15

-contains cell sap
-stores dissolved sugars,mineral ions and other substances