Epidermis, Gametes, Flowering Plants, and the Fungi Kingdom
Epidermis
The epidermis is the outermost layer of cells covering the leaves, stems, and roots of a plant.
It protects the plant from water loss, injury, and infection.
Cells are closely packed and often covered with a waxy cuticle to reduce evaporation.
In leaves, it contains stomata, which control gas exchange and transpiration.
Key Points:
Function: Protection
Found in: Leaves, stems, roots
Special feature: Waxy layer + guard cells
Gametes
Gametes are sex cells used for sexual reproduction.
They contain half the number of chromosomes (haploid).
Male gamete: Sperm (in animals), pollen grain (in plants)
Female gamete: Egg cell (in animals), ovule (in plants)
During fertilization, male and female gametes fuse to form a zygote, which grows into a new organism.
Key Points:
Haploid cells
Fusion = fertilization
Purpose: Reproduction
Flowering Plants
Flowering plants (Angiosperms) are plants that produce flowers and seeds enclosed in fruits.
They have roots, stems, leaves, and flowers.
Flowers are the reproductive organs:
Stamen (male) – produces pollen
Carpel (female) – contains ovules
After fertilization, the ovule becomes a seed and the ovary becomes a fruit.
Examples: Rose, Mango, Sunflower
Key Points:
Reproduce using flowers
Seeds inside fruits
Double fertilization occurs in plants
The Fungi Kingdom
Fungi are a separate kingdom of living organisms (not plants or animals).
They are eukaryotic, mostly multicellular, and heterotrophic (they can’t make their own food).
They feed by absorbing nutrients from dead or decaying matter — called saprophytic nutrition.
Cell walls are made of chitin, not cellulose.
They reproduce using spores.
Examples: Mushroom, Yeast, Mould
Key Points:
Heterotrophs
Cell wall = chitin
Feed on dead matter