Chapter 3: Photosynthesis Flashcards Preview

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Flashcards in Chapter 3: Photosynthesis Deck (107)
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1

Chlorophyll

The light-absorbing green-coloured pigment that begins the process of photosynthesis.

2

Porphyrin

The light-absorbing portion of the chlorophyll molecule, containing a magnesium atom surrounded by a hydrocarbon ring.

3

Cyanobacteria

The largest group of photosynthesizing prokaryotes.

4

Epidermis Layer

The transparent colourless layer of cells below the cuticle of a leaf, stem or root.

5

Mesophyll Layers

The photosynthetic cells that form the bulk of a plant leaf.

6

Guard Cells

Photosynthetic epidermal cells of a leaf or stem that form and regulate the size of an opening called a stoma.

7

Stomata

Openings on the surface of a leaf that allow for the exchange of gases between air spaces in the leaf interior and the atmosphere.

8

Transpiration

The loss of water vapour from plant tissues, primarily through stomata.

9

Vascular Bundles

A system of tubes and cells that transport water and minerals from the roots to the leaf cells and carry carbohydrates from the leaves to other parts of a plant, including the roots.

10

Stroma

The protein-rich semiliquid material in the interior of a chloroplast.

11

Thylakoids

A system of interconnected flattened membrane sacs forming a separate compartment within the stroma of a chloroplast.

12

Grana (singular: granum)

A stack of thylakoids

13

Lamellae (singular: lamella)

Unstacked thylakoids between grana

14

Thylakoid Membrane

The photosynthetic membrane within a chloroplast that contains light- gathering pigment molecules and electron transport chains.

15

Thylakoid Lumen

The fluid-filled space inside a thylakoid.

16

Light Reactions

The first set of reactions of photosynthesis in which light energy excites electrons in chlorophyll molecules, powers chemiosmotic ATP synthase, and results in the reduction of NADP+ to NADPH.

17

Carbon Fixation

The process of incorporating CO2 into carbohydrate molecules.

18

Calvin Cycle

A cyclic set of reactions occurring in the stroma of chloroplasts that fixes the carbon of CO2 into carbohydrate molecules and recycles enzymes.

19

Electromagnetic (EM) Radiation

A form of energy that travels at 3 X 10^8 m/s in wave packets called photons that include visible light.

20

Photons

Packets of EM radiation (also known as quanta)

21

Spectroscope

An instrument that separates different wavelengths into an electromagnetic spectrum.

22

Electromagnetic Spectrum

Photons separated according to wavelength.

23

Photosystems

Clusters of photosynthetic pigments embedded in the thylakoid membranes of chloroplasts that absorb light energy.

24

Action Spectrum

A graph illustrating the effectiveness with which different wavelengths of light promote photosynthesis.

25

Absorption Spectrum

A graph illustrating the wavelengths of light aborbed by a pigment.

26

β-carotene

A carotenoid pigment found in photosystems that also forms vitamin A in animals.

27

Xanthophylls

Pigments in chloroplast membranes that give rise to the yellow colour in autumn leaves.

28

Anthocyanins

Pigments in vacuoles that give rise to the red colour in autumn leaves.

29

Photosynthestically Active Radiation (PAR)

Wavelengths of light between 400 nm and 700 nm that support photosynthesis.

30

Ground State

The lowest possible potential energy level of an atom's electron.