Cell Wall: Occurrence and General Characteristics
Introduction to the cell wall, its presence in plants, fungi, and algae, and its non-living rigid nature.
What is Cell Wall: Occurrence and General Characteristics?
A complex carbohydrate (polysaccharide) that forms the main structural component of the cell walls of plants and some algae.
Key points
- Identify organisms possessing a cell wall.
- Describe the general characteristics of a cell wall.
- Differentiate cell wall composition in plants and fungi.
- Explain the functions of the cell wall.
Common exam trap
Confusing cell wall composition across different kingdoms.
Definitions
- Term
Cellulose
- Meaning
A complex carbohydrate (polysaccharide) that forms the main structural component of the cell walls of plants and some algae.
- Term
Chitin
- Meaning
A tough, flexible polysaccharide found in the cell walls of fungi and in the exoskeletons of arthropods.
- Term
Osmotic Lysis
- Meaning
The bursting of a cell due to excessive water uptake when placed in a hypotonic solution, prevented by a rigid cell wall.
Learning objectives
Identify organisms possessing a cell wall.
Describe the general characteristics of a cell wall.
Differentiate cell wall composition in plants and fungi.
Explain the functions of the cell wall.
Prerequisites
Basic cell structure (plasma membrane, cytoplasm).
Understanding of polysaccharides.
Common mistakes
Confusing cell wall composition across different kingdoms.
Assuming cell walls are present in all living organisms.
Overlooking the role of the cell wall in preventing osmotic lysis.
Mistaking the cell wall for a selectively permeable membrane.
Keywords
Cell wall
Plant cell
Fungal cell
Algae
Cellulose
Chitin
Structural support
Osmotic pressure
Plasma membrane
Practice preview
The cell wall in plants is primarily composed of:…
easy
Which of the following organisms possess a cell wall?…
easy
Which of the following statements about the cell wall is INCORRECT?…
easy