Unit 1: Cells and Proteins 4

Question 1

Photoreceptor systems are found in:

Answer 1

Archaea, Prokaryota and Eukaryota

Question 2

Archaea are what?

Answer 2

Single celled organisms with no defined nucleus

Question 3

Different groups of archaea can do

Answer 3

different things

Question 4

The haloarchae can do what?

Answer 4

Photosynthesise

Question 5

Haloarchae relies on ___________ for activation of ATP synthase

Answer 5

bacterial rhodopsin

Question 6

Bacterial rhodopsin consists of:

Answer 6

a retinal and a chromophore within a bacterial opsin

Question 7

The retinal-opsin complex is known as?

Answer 7

Rhodopsin

Question 8

Bacterial Rhodopsin Process: Stage 1, sunlight strikes a bacterial rhodopsin molecule causing the retinal to undergo?

Answer 8

Photoisomerisation

Question 9

Bacterial Rhodopsin Process: Stage 2, Photoisomerisation of the retinal causes a?

Answer 9

conformational change in the opsin

Question 10

Bacterial Rhodopsin Process: Stage 3, The retinal’s conformational change causes activation of which molecule?

Answer 10

Rhodopsin molecule

Question 11

Bacterial Rhodopsin Process: Stage 4, The activated rhodopsin molecule begins to?

Answer 11

Pump protons out of the cell

Question 12

Bacterial Rhodopsin Process: Stage 5, What force causes the protons to flow back into the cell?

Answer 12

The electrochemical gradient

Question 13

Bacterial Rhodopsin Process: Stage 6, The protons flowing back into the cell due to the electrochemical gradient begin driving what?

Answer 13

ATP Synthase

Question 14

Bacterial Rhodopsin Process: Stage 7, ATP synthase begins to …

Answer 14

Synthesise Pi with ADP

Question 15

Bacterial Rhodopsin Process: Stage 8, Therefore what molecule is being generated by this whole process?

Answer 15

ATP

Question 16

In animals, retinal is combined with a

Answer 16

membrane protein opsin

Question 17

Retinal is a form of

Answer 17

Vitamin A

Question 18

When stimulated by light, the retinal undergoes

Answer 18

photoisomerisation

Question 19

During photoisomerisation the retinal goes from 11-cis-retinal into

Answer 19

all-trans-retinal

Question 20

What is the process caused by photoisomerisation that results in retinal going from 11-cis-retinal to all-trans-retinal called?

Answer 20

Bleaching

Question 21

What happens in the process of Bleaching?

Answer 21

11-cis-retinal goes to all-trans-retinal

Question 22

Bleaching of a retinal induces a ________ change

Answer 22

conformational

Question 23

Bleaching stimulates a conformational change which activates the g-protein called?

Answer 23

Transducin

Question 24

Where is the g-protein transducin located?

Answer 24

On the inside of the membrane

Question 25

Light Transduction: Stage 1, When stimulated by a photon, a rhodopsin molecule activates hundreds of

Answer 25

transducin molecules

Question 26

A rhodopsin is what type of cell?

Answer 26

Rod cell

Question 27

A photopsin is what type of cell?

Answer 27

Cone cell

Question 28

Light Transduction: Stage 2, Transducer activates what enzyme located on the intracellular side of the membrane?

Answer 28

Phosphodiesterase

Question 29

Light Transduction: Stage 3, The activation of phosphodiesterase leads to the breakdown of a 1000 of what molecule per second?

Answer 29

cGMP

Question 30

Light Transduction: Stage 4, The breakdown of cGMP causes what to become very sensitive?

Answer 30

rhodopsin-based systems

Question 31

Light Transduction: Stage 5, The decrease in cGMP levels causes what to close?

Answer 31

Ligand-gated Na+ channels

Question 32

Light Transduction: Stage 6, The close of the ion channels prevents the release of ?

Answer 32

inhibitory neurotransmitters

Question 33

Light Transduction: Stage 7, The prevention of the release of inhibitory neurotransmitters allows the sensory synapse to become stimulated and do what?

Answer 33

Transmit a nerve impulse to the visual centres of the brain

Question 34

In vertebrates retina rod cells and cone cells both contain ?

Answer 34

opsins which contain retinal

Question 35

Many rods are connected to a single

Answer 35

neuron

Question 36

Being connected to a single neutron maximises a rode cells sensitivity to

Answer 36

light

Question 37

Do rod cells detect colour?

Answer 37

No

Question 38

There are three types of cone cells, but each contains a:

Answer 38

rhodopsin analogue and photopsin.

Question 39

It is the _____ connected to the retinal that varies between the cone cells

Answer 39

opsin

Question 40

Each type of opsin in a cone cells is sensitive to a?

Answer 40

narrower range of wavelengths

Question 41

Each type of cone cells is sensitive to different ranges of

Answer 41

light wavelength

Question 42

What is it that allows the detection of colour by cone cells?

Answer 42

The specificity of the opsins to narrower range of wavelengths

Question 43

L cone cells react to

Answer 43

red

Question 44

M cone cells react to

Answer 44

green

Question 45

S cone cells react to

Answer 45

blue

Question 46

Photosynthesis is the process of converting light energy into

Answer 46

chemical energy

Question 47

One single pigment contains:

Answer 47

Chlorophyll a, chlorophyll b, phycobilins and carotenoids

Question 48

Groups of pigments are bound together in a?

Answer 48

Thylakoid membrane

Question 49

Groups of thylakoids band together in a geometric pattern to form?

Answer 49

Grana

Question 50

Within a chloroplast, Groups of Grana are joined together by a road like structure called?

Answer 50

Lamella

Question 51

The inside of a thylakoid is called the?

Answer 51

Lumen

Question 52

Surrounding the thylakoid and lamella in the chloroplast is what aqueous fluid?

Answer 52

Stroma

Question 53

A chloroplast has three parts to its membrane which are:

Answer 53

The inner membrane, the inner membrane space and the outer membrane

Question 54

The light energy trapped by the pigments in the chloroplast is used to

Answer 54

split H2O and generate ATP & NADPH

Question 55

Photolysis is the splitting of?

Answer 55

Water

Question 56

The hydrogen and electrons produced in photolysis reduce what molecule?

Answer 56

NADP to NADPH

Question 57

The reduced NADPH carries what to the next stage, carbon fixation

Answer 57

Hydrogen and Electrons

Question 58

Photophosphorylation is the conversion of:

Answer 58

ADP + Pi ---> ATP

Question 59

Trapped light energy is used to pump what molecule from the stroma across into the thylakoid space?

Answer 59

H+

Question 60

H+ is pumped from the stroma into the

Answer 60

thylakoid space

Question 61

The diffusion of H+ back into the stroma drives what process?

Answer 61

ATP synthase

Question 62

Chlorophyll a channels electrons to

Answer 62

other parts of the electron transport chain

Question 63

Accessory pigments do what with their trapped energy?

Answer 63

Transfer it to chlorophyll a

Question 64

Photosystem 2 uses the energy of electrons to split

Answer 64

water

Question 65

The electrons generated by the splitting of water are passed onto other intermediaries such as

Answer 65

plastiquinones

Question 66

Electrons being passed onto intermediaries results in more H+

Answer 66

accumulating in the thylakoid space

Question 67

The large pool of thylakoid H+ leaks back across the thylakoid membrane and down the electrochemical gradient back to the

Answer 67

stroma

Question 68

H+ leaking back into the stroma drives what

Answer 68

ATP synthase to generate ATP