Chapter One - Light And Life

Question 1

Light

Answer 1

The portion of the electromagnetic spectrum that humans can detect with their eyes.

Question 2

Photon

Answer 2

Discrete particles or packets of energy.

Question 3

Electromagnetic radiation

Answer 3

Self-propagating waves which consist of both electrical and magnetic waves which are orientated at 90 degrees to each other.

Question 4

Pigment

Answer 4

A molecule that can absorb photons of light.

Question 5

Wavelength

Answer 5

The distance between two successive peaks of electromagnetic radiation.

Question 6

Retinal

Answer 6

A pigment molecule involved in vision.

Question 7

Action spectrum

Answer 7

Graph produced by plotting the effectiveness of light at each wavelength in driving photosynthesis.

Question 8

Photoreceptor

Answer 8

A sensory receptor that detects the energy of light.

Question 9

Rhodopsin

Answer 9

The retinal-opsin photopigment.

Question 10

NADPH

Answer 10

Nicotinamide adenine dinucleotide phosphate

Question 11

ATP

Answer 11

Adenosine triphosphate

Question 12

Pigments and conjugated systems

Answer 12

Double/single bonds which delocalize electrons making the pigment molecules more stable by lowering its overall energy.

Question 13

Eye

Answer 13

The organ animals use to sense light.

Question 14

Phytochrome

Answer 14

A blue-green pigmented plant chromoprotein involved in the regulation of light-dependent growth process.

Question 15

Photomorphogenesis

Answer 15

The normal developmental process activated when seedlings are exposed to light. (Phytochrome facilitates this)

Question 16

Carotenoids

Answer 16

Molecule of yellow-orange pigment by which light is absorbed in photosynthesis.

Question 17

Absorption Spectrum

Answer 17

Curve representing the amount of light absorbed at each wavelength.

Question 18

Gamma Rays

Answer 18

0.00001 nm - 0.1 nm (10 to the power of -6 - 10 to the power of -2)

Question 19

X-rays

Answer 19

0.1 nm - 10 nm (10 to the power of -2 to 10)

Question 20

UV radiation

Answer 20

10 nm - 390 nm

Question 21

Visible Light

Answer 21

390 nm - 750 nm (blue to red) (Textbook says 400 to 700 in text)

Question 22

Infrared

Answer 22

750 nm - 10 000 000 nm (750 to 10 to the power of 6)

Question 23

Microwaves

Answer 23

10 000 000 nm - 1 m (10 to the power of 6 to 1)

Question 24

Radio

Answer 24

1 m - 10 000 m (1 to 10 to the power of 3)

Question 25

Circadian Rhythms

Answer 25

Any biological activity that is repeated in cycles, each about 24 hours long, independently of any shifts in environmental conditions.

Question 26

ADP

Answer 26

Adenosine Diphosphate

Question 27

Bioluminescence

Answer 27

An organism that glows or releases a flash of light, particularly when absorbed.