Question

Describe how each of the following adaptations allowed plants to invade new habitats and/or become more successful competitors:

•Spores and spore tetrads

•Lignin, vascular tissue, stomata, and roots

•Seeds

•Ovary

•Double fertilization and triple fusion

•Flowers

Use basic terminology in each individual description.

Answer 1

Adaptations allowed plants to invade new habitats and/or become more successful competitors:

Spores and spore tetrads

Spores : Spores are the single-celled reproductive unit of nonflowering plants, bacteria, fungi, and algae.

• Unlike gametes in sexual reproduction, spores do not need to fuse in order for reproduction to take place
• Organisms use spores as a means of asexual reproduction
• These spores are dormant and serve a protective role by safeguarding bacteria from extreme environmental conditions
• Helps organism to wait for favourable conditions and also helps them disperse over large area
• organisms can both sexually and asexually reproduce in order for it to disperse and to survive over long periods of time
• Some bacteria produce a special type of spore called an endospore, which can withstand such extremes as boiling and freezing temperatures, and ultraviolet radiation

Endospores enable bacteria to lie dormant for extended periods, even centuries. There are many reports of spores remaining viable over 10,000 years, and revival of spores millions of years old has been claimed

Spores Tetrad :The tetrad is the four spores produced after meiosis of a yeast or other Ascomycota, Chlamydomonas or other alga, or a plant. After parent haploids mate, they produce diploids

• Under appropriate environmental conditions, diploids sporulate and undergo meiosis

Lignin, vascular tissue, stomata, and roots

Lignin: All land plants evolved from aquatic green algae and scientists have long believed that lignin evolved after plants took to land as a mechanical adaptation for stabilizing upright growth and transporting water from the root

• It is  key structural materials in the support tissues of vascular plants and some algae.
• The crosslinking of polysaccharides by lignin is an obstacle for water absorption to the cell wall
• This strength to plants helps them to survive and inhabit many terrains and regions

vascular tissue: It is  any plant possessing vascular tissue (xylem and phloem), including ferns, conifers, and flowering plants

• Vascular tissue is specialized tissue that transports water, nutrients, and food in plants
• Primitive plants dont have vascular tissue thus they have limited grown and limited region where they can live
• it also give mechanical support to plant
• it also helps them grow taller as water and food can be transported to any part of body against gravity , also helps them to grow taller

stomata: Allow carbon dioxide to diffuse into the leaf and oxygen to diffuse out

• Stomata serve a very important function to plants, allowing them to use photosynthesis to make energy for survival
• Many desert plants have very small stomata and fewer stomata than those of other plants.
• This adaptation helps cacti reduce water loss by keeping the hot, dry wind from blowing directly across the stomata.
• Stomata helps plant to live in many regions as there are many adapatations of stomata which helps plants to survive in desert

Roots: Root is that part of a vascular plant normally underground. Its primary functions are anchorage of the plant, absorption of water and dissolved minerals and conduction of these to the stem, and storage of reserve foods

• It is not only provide mechanical support to plant but also helps them to absorb water
• Plant dont need to live near pond , shady or damp place .
• That is why vascular plants found in vast habitats like desert , tundra etc

Seeds: A seed is an embryonic plant enclosed in a protective outer covering. The formation of the seed is part of the process of reproduction in seed plants

• Seeds go dormant and wait for favourable condition to sprout again
• Seeds can disperse over large area and new habitat via winds, animals etc
• Dispersion to other habitats helps to occupy new niche that were empty

• Ovary: It is enlarged basal portion of the pistil, the female organ of a flower. The ovary contains ovules, which develop into seeds upon fertilization.
• The ovary itself will mature into a fruit, either dry or fleshy, enclosing the seeds
• It produce fruit which is eaten by vast majority of organism and hepls in their dispersion
• This is also why angiosperms are very successful than other plants

Double fertilization and triple fusion: It is a process involved in the sexual reproduction of angiosperms.

• Triple fusion is a fusion that involves a sperm nucleus and two polar nuclei which occurs in the double fertilization in a seed-bearing plant that results in the endosperm formation.
• The fusion process occurs in the embryo sac of the angiosperms
• The end result is outcome of the process of triple fusion is the formation of the endosperm
• The function of endosperm is to provide stored food supply in the angiosperms seeds to nourish an embryo
• During germination it is very necessary and its harsh conditions its like boon

flowers: It is only found in angiosperms

• It come in many shapes and sizes which main function is to attract pollinators
• POllination is very necessary for diversity and variation , it isno wonder why these plants are so diverse
• Flowers can be very specific to its pollinators thus somwhow force an animal to co-evolve with it .
• like vanilla can be only pollinated by Melioona bee