AP BIOLOGY

PLANTS

PLANT TISSUE

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
Which type of plant cell has a thick primary cell wall and no secondary cell wall? Hint:It is used for elasticity of a growing parts of the plant.
A
parenchyma
B
collenchyma
C
schlerenchyma
D
guard cells
Explanation: 

Detailed explanation-1: -Collenchyma is made of long and thick-walled cells with no intercellular spaces. Their cell wall is composed of cellulose, hemicellulose and pectin.

Detailed explanation-2: -Collenchyma, like parenchyma, lack secondary cell walls but have thicker primary cells walls than parenchyma. They are long and thin cells that retain the ability to stretch and elongate; this feature helps them provide structural support in growing regions of the shoot system.

Detailed explanation-3: -Collenchyma tissue possesses elongated cells with irregular thickening, mainly at the corners. They possess only thick primary cell wall made of cellulose and pectin.

Detailed explanation-4: -Sclerenchyma tissue (Figure 5) is composed of sclerenchyma cells, which are usually dead at maturity (i.e., have lost their protoplasts). They characteristically contain very thick, hard secondary walls lined with lignin; consequently, sclerenchyma provides additional support and strength to the plant body.

Detailed explanation-5: -So, the correct answer is ‘Sclerenchyma’.

There is 1 question to complete.