Plastids Types and Functions

Questions and Answers

Flower cells

Stem cells

Root cells (correct)

Mesophyll cells of the leaves

To store carbohydrates

To trap light energy essential for photosynthesis (correct)

To store oils and fats

To synthesize proteins

Grana

Thylakoid

Stroma (correct)

Lumen

Chromoplasts Signup and view all the answers

Variable shapes such as lens-shaped, oval, spherical, discoid or even ribbon-like Signup and view all the answers

To trap light energy essential for photosynthesis Signup and view all the answers

Thylakoids Signup and view all the answers

Amyloplasts Signup and view all the answers

Study Notes

Found in all plant cells and euglenoids, easily observed under the microscope due to their large size
Can be classified into three types based on the type of pigments they contain

Chloroplasts: contain chlorophyll and carotenoid pigments, responsible for trapping light energy essential for photosynthesis
Chromoplasts: contain fat-soluble carotenoid pigments, such as carotene and xanthophylls
Leucoplasts: colorless plastids of varied shapes and sizes, store nutrients, and include:
- Amyloplasts: store carbohydrates (starch), e.g., potato
- Elaioplasts: store oils and fats
- Aleuroplasts: store proteins

Double membrane bound, with inner membrane being relatively less permeable
Stroma: space limited by the inner membrane, containing enzymes required for carbohydrate and protein synthesis
Thylakoids: organized, flattened, membranous sacs in the stroma, arranged in stacks (grana)
Grana: stacks of thylakoids, resembling piles of coins
Stroma lamellae: flat, membranous tubules connecting thylakoids of different grana
Lumen: space enclosed by the thylakoid membrane
Chlorophyll pigments: present in the thylakoids