WE2CANDOIX

Thursday, July 16, 2015

LINES AND ANGLES: MCQ

Class-IX

MCQ (Multiple Choice Questions):

Q1. The complementary angle of 62. a. 117 b. 37 c. 27 d. 17

Q2. The supplementary angle of 73 a. 17 b. 107 c.127 d. 287

Q3. If two complementary angles are in the ratio 7 : 11, then the angles are a.70 ,110 b. 110 ,70 c. 45 , 135 d. 25 , 65

Q4. If one angle is three times its supplement, then the angles are a. 30 ,150 b 35 , 140 c. 45 , 135 d. 22 , 65

Q5. If the sum of two adjacent angles is 100 and one of them is 35 , then the other is a. 70 b. 65 c. 135 d. 145

Q6. In the adjoining figure 6 , a ray stands on a line. If x= 30, , then y is equal to a. 20 b. 24 c. 25 d. 36

Q7. In the adjoining figure 7, rays OP and OQ stand on a line. If x: y = 2 : 3 then x & y respectively are
a. 84 ,56 b. 56 , 84 c. 20, 80, d. 30 , 20

Q8. In the adjoining figure 8, the value of x is
a. 35 b 30 c 25 d 18

FIG. 6 FIG 7 FIG 8

Q9. Two angles measure (70 + 2x ) and (3x- 15 ) . If each angle is the supplement of the other then the value of is

a. 25^o b. 30^o c. 20^o d. 25^o

Q10. In the adjoining figure 10 value of x is a.18^o b. 15^o c. 12^o d. 10^o

Q11. In the adjoining figure11, if m || n , then ∠4 + ∠7 is equal to

a. 90 b. 120 ` c. 150 d. 180

Q12. In the adjoining figure 11, if m || n , and∠1 = 50 , then ∠2 is equal to

a. 130^o b. 120 ` c. 50 d. 40

Q13. In the adjoining figure 13, If ∠a : ∠b = 2 : 3, then the measure of ∠h is

a.72 b.108 c.120 d.150

FIG. 10 FIG 11 FIG 13

Q14. In the adjoining figure14, AB || CD and AB || EF. The value of x is

a.40 b. 50 c. 60 d.70

Q15. If the angles of a triangle are in the ratio 2 : 3 : 7,then the angles of the triangle are :

a.20 ,30 ,70 b. 24 , 36 , 84

c.30 ,45 ,105 d. 30 , 40 , 70

Q16. In the adjoining figure, if AB || DC, then the measure of angle ∠AOC is

a. 70 b. 80 c. 90 d. 100

FIG 14

Q17. In the adjoining figure, the value of x is

a.45 b.40 c. 55 d. 30

Q18. In the adjoining figure, the value of x is

a. 35 b. 55^o c.45^o d. 35^o

FIG. 16 FIG 17 FIG 18

Q19. In the adjoining figure, the measure of ∠AED is

a. 110 b.120 c. 130 d. 140

Q20. In the adjoining figure, If QP || RT, then x is equal to

a.75^o b.70^o c. 65^o d. 55^o

Q21. In the adjoining figure, then x is equal to

a.51 b. 56 c. 61 d. 66

FIG. 19 FIG 20 FIG 21

Q22. A, B, C are the three angles of a triangle. If ∠A – ∠B =15 and ∠B – ∠C = 30 , then angles A, B, C are

a. 80 , 65 35 b.80 , 35 , 65 c. 65 , 80 , 35 d. 35 , 65 80

Q23. DELETED

Q24. In the adjoining figure 24, find the values of and then show that AB || CD.

FIG. 24

Q25. In the adjoining figure 25, AB ‖ CD. If ∠APQ = 50 and ∠PRD = 127 , find x and y.

Q26. In the adjoining figure 26, AB ‖ CD and EF CD. If ∠GED = 126 , find ∠AGE, ∠GEF and ∠FGE.

Q27. In the adjoining figure 27, QT ⊥ PR. If ∠SPR = 30 and ∠TQR = 40 , Find x and y

FIG. 25 FIG26 FIG 27

Q28. In the adjoining figure28, if CD ‖ EF, find the value of x.

Q29. In the adjoining figure29, find the value of x

Q30. In the adjoining figure30, PQ ‖ SR. If QP ⊥ SP, then find the values of x and y

FIG. 28 FIG 29 FIG 30

Q31. In adjoining figure31 , lines XY and MN intersect at O. If ∠ POY = 90° and a : b = 2 : 3, find c.

FIG 31

Tuesday, July 14, 2015

TISSUE

1. How are simple tissues different from complex tissues in plants?

Simple tissue	Complex tissue
These tissues consist of only one type of cells.	These tissues are made up of more than one type of cells.
The cells are more or less similar in structure and perform similar functions.	Different types of cells perform different functions. For example, in the xylem tissue, tracheids help in water transport, whereas parenchyma stores food.
Three types of simple tissues in plants are parenchyma, collenchyma, and sclerenchyma.	Two types of complex permanent tissues in plants are xylem and phloem.

2. Differentiate between parenchyma, collenchyma and sclerenchyma, on the basis of their cell wall.

Parenchyma	Collenchyma	Sclerenchyma
Cell walls are relatively thin, and the cells in parenchyma tissues are loosely packed.	The cell wall is irregularly thickened at the corners, and there is very little space between the cells.	The cell walls are uniformly thickened, and there are no intercellular spaces.
The cell wall in this tissue is made up of cellulose.	Pectin and hemicellulose are the major constituents of the cell wall.	An additional layer of the cell wall composed mainly of lignin is found.

3. What are the functions of the stomata?

Functions of the stomata:

(i) They allow the exchange of gases (CO₂ and O₂) with the atmosphere.

(ii) Evaporation of water from the leaf surface occurs through the stomata. Thus, the stomata help in the process of transpiration.

Difference between Collenchyma & Sclerenchyma

Difference between Collenchyma & Sclerenchyma

Collenchyma	Sclerenchyma
1. Living cells contain cytoplasm.	Dead cells are empty.
2. Cell walls are cellulosic.	Cell walls are lignified.
3. Lumen of the cell is wide	Lumen of the cell is narrow
4. The thickening of the cell wall is not uniform.	Thickening of cell wall is uniform.
5. It provides mechanical support & elasticity to the plant body.	It is chiefly a mechanical tissue.

SCLERENCHYMA

SCLERENCHYMA

Primarily meant for providing mechanical support and protection to different parts of the plant body.

Hence, sclerenchyma occurs in almost all the parts of the plant body, including root, fruit and seed.

It provide hardness and stiffness to the plant

The sclerenchyma cells are usually elongated, with tapering ends. These are matured dead cells. Its wall are thickened by deposition of lignin hence are refered as lignified walls. The walls are so think that there is hardly any internal space. Such cells are commonly described as sclerenchyma fibres. In some cases, the cells are shorter and irregular in shape. Such cells are commonly described as sclereids or stone cells.

EPIDERMIS

Q: What is the role of epidermis in plants?

Ans: Epidermis present on the outer surface of the entire plant body. Its function is to protect. Hence the cells of the epidermal tissue form a continuous layer without any intercellular space. Most cells are relatively flat. Usually there outer and side wall are thicker than the inner wall (Why? – Its main function is protection hence outer wall is thicker). On aerial parts of plants it secrets a waxy water-resistant layer to protect against the loss of water, mechanical injury and invasion by parasitic fungi.It performs the following important functions:

(i) It protects the plant body

(ii) It protects the plant against mechanical injury

(iii) It allows exchange of gases through the stomata