- 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.
Answer:
The correct option is cell wall and central vacuole.
Explanation:
The cell wall can be described as an additional membrane around the cell membrane which is present in the plant cells but is absent in animal cells.
The plant cells also have a vacuole located at the center on the cell. The central vacuole is absent in animal cells. It stores the waste and other materials for the plant cell. The plant vacuole also provides support to the cell.
Answer:
4 Charles Darwin was not able to explain the variation
Carbohydrates are naturally occurring sugars, starches and fiber in food. All carbohydrates are made up of sugar molecules. Sugar molecules linked together form starches and fiber. In the body, starches and sugars are broken down in the digestive system to glucose.
Dna replication so it replicates your DNA to occur
