- 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.
B) All living things are made of cells.
<span>C. neutral, with the number of protons equaling the number of electrons.
is the right answer
because number of neutrons vary from atom to atom</span>
1.) what is the importance of understanding the structure and behavior of the subatomic particles of atoms?
- <u>we can find out how atoms combine and form many compunds</u>.
- <u>By learning about atomic structure, we can find out how atoms collide.</u>
- <u>By learning about atomic structure, we can find out why atoms do not have mass.</u>
2.) What is the importance of quantum numbers?
- <u>Quantum numbers are important because they can be used to determine the electron configuration of an atom and the probable location of the atom's electrons.</u>
- <u>Quantum numbers are also used to understand other characteristics of atoms, such as ionization energy and the atomic radius</u>
3.) What are the andvantages of usingdata/information using electron configuration?
- <u>T</u><u>he electron configuration of different atoms is useful in understanding the structure of the periodic table of elements. </u>
- <u>The concept is also useful for describing the chemical bonds that hold atoms together.</u>
