Key Points

Nutrition in Plants

Important Points

  • Green plants are autotrophs.
  • Photosynthesis needs chlorophyll, sunlight, water and CO₂.
  • Oxygen is released as a by-product of photosynthesis.
  • Not every plant is green — parasites and saprotrophs exist too.

Remember This

  • Photosynthesis equation — you should be able to write it from memory.
  • Cuscuta = parasite ; Pitcher plant = insectivorous ; Mushroom = saprotroph.

Exam Tips

  • Draw a simple diagram of a leaf cross-section showing chloroplasts.
  • Remember the four essentials of photosynthesis: **C**arbon dioxide, **W**ater, **S**unlight, **C**hlorophyll (CWSC).

Definitions

Autotroph
An organism that makes its own food from simple substances.
Photosynthesis
The process by which green plants make food using sunlight, water and CO₂.
Chlorophyll
The green pigment in leaves that traps sunlight.
Parasite
An organism that lives on another and takes food from it.