Cells that keep dividing
Growth needs a tissue of dividing cells.
Grass after the cows
Cows graze on a field of grass, but a few days later the grass has grown again.
What must the plant have to regrow?
What this lesson covers
The idea
Plant growth in length, in girth, and regrowth after cutting or grazing all require actively dividing cells, which together form meristematic tissue.
Grass after the cows
Cows graze on a field of grass, but a few days later the grass has grown again.
What must the plant have to regrow?
- Cells that keep dividing
- Cells that have stopped dividing for good
- Only dead cells
Three kinds of growth
Press each button and look at the orange dots.
Dividing cells again
Growing taller, growing thicker and growing back after being cut are three different kinds of growth. But each one needs cells that divide actively. A tissue made of such cells is called a meristematic tissue.
Plant growth in length, in girth, and regrowth after cutting or grazing all require actively dividing cells, which together form meristematic tissue.
Notes
Growth in length, girth and regrowth need actively dividing cells: meristematic tissue.
Check yourself
Which tissue is made of actively dividing cells?
The stem of a tree becomes thicker with time. This is growth in…
Grass grows again after grazing animals have eaten it. This regrowth needs…
What do growth in length, growth in girth and regrowth have in common?
- Meristematic tissue — correct. Yes!
- Epidermis. The epidermis is the outermost protective layer of a plant, not a tissue of dividing cells.
- Xylem. Xylem is a conducting tissue. It transports water and minerals.
- length. Length means the height of the stem and the depth of the roots. Becoming thicker is girth.
- girth — correct. Yes!
- regrowth. Regrowth means growing again after cutting or grazing.
- cells that cannot divide. Cells that cannot divide cannot make the new cells that regrowth needs.
- fewer cells than before. Regrowth adds new cells, which needs cells that divide.
- actively dividing cells — correct. Yes!
- Each needs actively dividing cells — correct. Yes!
- Each happens only at the tip of the stem. Growth in girth makes the stem thicker, which is not growth at its tip.
- Each happens when cells stop dividing. The opposite is true. Each needs cells that divide actively.