Metabolism Pt 2 (Intro to photosynthesis)

Question 1

What are leaves

Answer 1

• The photosynthetic organ of plants
• They have waxy cuticles that protect them from over absorption of water and excessive sunlight
• Special photosynthetic cells called mesophyll
• The guard cells that create tiny openings called stomata, which regulates gas exchange and allows water vapour to entre and exit by transpiration
• Vascular bundles that transport water and minerals from the roots to leaves and carbohydrates from leaves to roots

Question 2

What are pigments?

Answer 2

• The green colored pigment is known as chlorophyll and it absorbs light
• Components such as the porphyrin ring and hydrocarbon tail
  Porphyrin
• has a mg atom in the center
• Alternating rings of double and single bonds
• Delocolized e- abosorbs the light and begins photosynthesis
  Hydrocarbon tail
• Anchors the chorophyll molecule to the membrane

Question 3

Which group does cholorphyll a contain

Answer 3

Chlorophyll a contains the methyl group

Question 4

Which group does chlorophyll b contain

Answer 4

chlorophyll b contains the aldehyde group

Question 5

Explain Light energy reactions

Answer 5

1)photonexcitation - Photon is absobed and the electron is the chlorophyll gets excited
2)electron transport - Excited electron goes through a series of membrane bound electron acceptors, which results in protons getting pumped through photosynthetic membranes, resulting in the making of H+ pools and reducing the electron acceptor
3) Chemiosmosis: movement of protons in ATP synthase complex to drive the phosphorylation of ADP - ATP

Question 6

What is exicitation

Answer 6

• The absorption of energy by an election
• Ground state to excited state
• Higher potential energy

Question 7

What is fluorescence

Answer 7

Rapid loss of energy in the form of light

Question 8

Why does chlorphyll not fluorence

Answer 8

• When the electron exicties while the chlorophyll is in the membrane it gets captured by the primary electron acceptor

Question 9

Give an example of a redox reaction

Answer 9

• Chlorophyll is oxidized
• Primary electron acceptor is reduced

Question 10

What contains the photosystem

Answer 10

antenna complex and reaction center

Question 11

Explain the antenna complex

Answer 11

-Consists of # of chlorophyll molecules and accessory pigments in the thylakoid membrane
- Photon gets absobed and the energy gets transported from pigmen to pigment until it reaches the chlorophyll a molecule, which is located in the reaction center

Question 12

Explain the reaction center

Answer 12

Transmembrane protein complex which contains the chlorophyll a molecule, whos electrons absorb light energy and start photosynthesis