Structure of Chloroplast and the Role of Pigments

Question 1

the process by which plants use sunlight, water, and carbon dioxide to create oxygen and energy in the form of sugar.
- occur in chloroplast

Answer 1

photosynthesis

Question 2

plant cell organelles that convert light energy into relatively stable chemical energy via the photosynthetic process. By doing so, they sustain life on Earth
- is a cell organelle in most
autotrophs that can convert solar energy
into reusable chemical energy.

Answer 2

chloroplast

Question 3

a pigment present in all green plants and a few other organisms. It is required for photosynthesis, which is the process by which light energy is converted into chemical energy.
- greenish pigment which
captures the energy of sunlight.

Answer 3

chlorophyll

Question 4

a generic term for a molecule that absorbs light and has a color.
- also have importance related to food production in plants
- organic molecules
- selectively absorb light of specific wavelengths
- built in thylakoid membrane (for photosynthesis 1 and 2)

Answer 4

pigment/photopigment

Question 5

What does reflected light do?

Answer 5

gives each pigment its characteristic color.

Question 6

an organism that can produce its own food using light, water, carbon dioxide, or other chemicals. Because they produce their own food, they are sometimes called producers. Plants are the most familiar type
- they perform this in their chloroplast

Answer 6

autotrophs

Question 7

parts of chloroplast

Answer 7

• inner and outer membrane (chloroplast envelope)
• intermembrane space
• stroma
• thylakoid (grana/granum)
• lamella
• lumen

Question 8

part of chloroplast

contains porins and is therefore freely permeable to small molecules.

Answer 8

outer membrane

Question 9

part of chloroplast

the region between the inner membrane and the outer membrane of a mitochondrion or a chloroplast. The main function is nucleotide phosphorylation, mitochondrial energetics and apoptosis

Answer 9

intermembrane space

Question 10

part of chloroplast

fluid filling up the inner space of the chloroplasts which encircles the grana and the thylakoids. In addition to providing support to the pigment thylakoids, they are now known to contain chloroplast DNA, starch, and ribosomes along with enzymes needed for the Calvin cycle.

Answer 10

stroma

Question 11

part of chloroplast

tiny compartments found inside chloroplasts. Their role is to help absorb sunlight in order for photosynthesis to occur. They contain all of the chlorophyll that the plant has which, in turn, allows for the absorption of sunlight.

Answer 11

thylakoid

Question 12

part of chloroplast

• stack of thylakoid
• increases the surface area of thylakoid membranes thereby elevating the sugar production of plants through the process of photosynthesis.

Answer 12

grana/granum

Question 13

part of chloroplast

connect thylakoids of two different grana. They increase the efficiency of photosynthesis by keeping grana at a distance so that they do not clutter together. They are also known as stroma thylakoids. They ensure that maximum energy from sunlight is captured in photosynthesis.

Answer 13

lamella

Question 14

part of chloroplast

a continuous aqueous phase enclosed by the thylakoid membrane. It plays an important role in photophosphorylation during photosynthesis. During the light-dependent reaction, protons are pumped across the thylakoid membrane into this making it acidic down to pH 4

Answer 14

lumen

Question 15

What does the color of the plants do?

Answer 15

• attract consumers
• allows them to become the primary producers in ecosystems by harnessing solar energy to produce high-energy organic molecules.

Question 16

how do we see colors

Answer 16

through the photo receptors in our eyes (what we see is the reflected light)

Question 17

principal pigment

Answer 17

chlorophyll A

Question 18

this pigment participates directly in light reactions which absorbs mainly blue, violet, and red colors of visible light (Attached to functional group CH3 - methyl group)
- all plants, algae, and cyanobacteria

Answer 18

chlorophyll A (C55H72MgN4O5)

Question 19

Accessory Pigments - light-absorbing compounds, found in photosynthetic organisms, that work in conjunction with chlorophyll a.

Answer 19

• Chlorophyll B, C, D
• Carotenoids
• Phycobilins

Question 20

absorbs mainly blue and orange light but reflects olive green (attached to functional group CHO - Aldehyde)
- does not participate directly in light reactions
- present only in green algae and higher plants (volvox)
- breaks down faster than the other pigments

Answer 20

chlorophyll B (C55H70MgN4O6)

Question 21

difference of chlorophyll a and b

Answer 21

functional group

Question 22

where is chlorophyll c (C55H30MgN4O5) present
(blue-green color)

Answer 22

brown algae, members of family chromista, etc.

Question 23

where is chlorophyll d present

Answer 23

red algae

Question 24

various shades of red, yellow, and orange
- absorbs mainly violet, blue, and green light
- appear once the chlorophyll breaks down
- evident in autumn leaves in temperate regions and in many of our fruits and vegetables, such as ripe bell peppers.
- This pigment is essential in
photoprotection. These pigments also convey
light energy harvested from other bands of the
visible light from the sun.

Answer 24

carotenoids

Question 25

the biochemical process that helps organisms cope with molecular damage caused by sunlight.

Answer 25

photoprotection

Question 26

two types of carotenoids

Answer 26

• carotenes (alpha-carotene, beta-carotene, lycopene)
• xantophyll - lutein and fucoxanthin

Question 27

xantophylls vs. carotenes

Answer 27

xanthophylls (yellow/brown) contain oxygen atoms in the form of a hydroxyl group (making them slightly more hydrophilic) or epoxides while carotenes (red/orange) are molecules with only hydrocarbons and no oxygen.

Question 28

• found in red algae and cyanobacteria
• water-soluble, present in the aqueous cytoplasm or stroma of chloroplasts
• especially important for deep-sea red algae as they can utilize the blue light that can penetrate into deeper waters.

Answer 28

phycobilins

Question 29

(phycobilin) the bluish pigment present in
cyanobacteria

Answer 29

phycocyanin

Question 30

(phycobilin) the reddish pigment present in Rhodophyta

Answer 30

phycoerythrin

Question 31

the brown pigment (ex: kelps, diatoms, brown algae)

Answer 31

fucoxanthin

Question 32

yellow pigments (vegetables and fruits)

Answer 32

zeaxanthin

Question 33

yellow-brown pigments (papaya, prunes, etc)

Answer 33

xanthophylls

Question 34

purple/red pigments (berries)

Answer 34

anthocyanin

Question 35

what compound in xanthophyll creates the yellow pigment in leaves

Answer 35

lutein

Question 36

structure of chlorophyll

Answer 36

porphyrin head with magnesium core and phytol tail (hydrophobic)