PDF homework TRY NOW

Have you seen a cactus plant that is present in a desert? What are the thorny structures present in them? What is the role of the spines or thorns present in the cactus?
Cacti

The spines present in the cacti are the reduced form of leaves. The leaves are modified into the spines. The spines lessen the excessive transpiration and act as a defensive organ - to protect the plants from herbivorous animals. It is an adaptation that is present in the cacti.
To withstand the adverse conditions of the environment present in the habitat, organisms develop morphological, physiological, anatomical and reproductive features.
A feature or part of an organism that enables it to exist under the conditions present in the habitat is called adaptation
Classification of plants based on water availability:
Johannes Eugenius Bülow Warming in the year $$1909$$ classified plants based on the water requirements and water availability into threeecological groups:

1. Hydrophytes

2. Xerophytes

3. Mesophytes

Johannes Eugenius Bülow Warming
• Hydrophytes are plants that grow in or near water.
• Xerophytes are plants that grow in a dry habitat.
• Mesophytes are plants that grow in an environment that is neither very dry nor very wet.
Reference:
https://www.publicdomainpictures.net/en/view-image.php?image=365193&picture=green-cacti-background
https://commons.wikimedia.org/wiki/File:Eugen_Warming_by_Marius_Christensen.jpg
https://pxhere.com/en/photo/1592431
https://commons.wikimedia.org/wiki/File:Cactus_(Opuntia_phaeacantha)_flower.JPG
https://pixabay.com/de/photos/stiefm%c3%bctterchen-sommergarten-655455/