D. population and nutrients
- Xylem contains tracheids, vessels, xylem parenchyma and xylem fibre.
- Tracheids: They are elongated, tubular dead cells with tapering end walls.
- Vessels: These are also known as trachea. They are elongated, tubular dead cells. They are joined to each other by end to end forming a continuous pipe. The cells are thick and lignified.
- Xylem parenchyma: They are also called wood parenchyma. This is the only living tissue of xylem.
- Xylem fibre: They are dead cells with thick walled fibre.
- Phloem consists of sieve tubes, companion cells, phloem parenchyma and phloem fibres.
- Sieve tubes: These are elongated, tubular living cells arranged in a row, with their perforated end walls forming a sieve. They are non-nucleated. Their protoplasm are inter-connected through sieve plates. They possess vacuoles.
- Companion cell: They are elongated, lens-shaped cells containing dense cytoplasm and prominent nuclei. These cells maintain connection with sieve cells through pits.
- Phloem parenchyma: They are living thin walled parenchyma cells.
- Phloem fibre: They are also known as bast fibre. They are elongated fibre like sclerenchymatous dead cells with thick walls containing pits and interlocked ends. Phloem fibre are the only dead cells in phloem.
Hope you could get an idea from here.
Doubt clarification - use comment section.
35g car to reach on egg in 1.88 sec.
Its easy 40 because to add and divide.
Answer:
Carbon dioxide is a gas which is released in the atmosphere as greenhouse gas, burning of fossil fuel, released in respiration process. Rise in the levels of carbon dioxide and other gases has resulted in increase in global temperatures. Increase in carbon dioxide and temperatures are responsible for weather fluctuations and global warming.
Weather fluctuation means untolerated heat and lack of precipitation or rain. Weather fluctuations will affect seasons. Seasons are necessary for maintaining the life cycle of organisms. Inappropriate seasons due to climatic change will affect the life of living organisms.
Global warming is an issue which is mainly due to release of hot heat trapping gases from green house and other sources, increasing the atmospheric temperature. This will result in melting of ice from glaciers in world. The inhabiting animals living in the glaciers will suffer a lot from this as they cannot tolerate warm climatic conditions.
