Properties of Triangles

Q.

In the given fig. a circle is inscribed in a quadrilateral ABCD in which $\angle$B = ${90}^0$. If AD = 23 cm AB = 29 cm and DS = 5 cm, find the radius of the circle (in cm).

Q.

In a circle, O is the centre and $\angle$COD is right angle. AC = BD and CD is the tangent at P. Which of the following are true, if the radius of the circle is 1 m?

1. BD = 41.42 cm

2. OD = 141.42 cm

3. PD = 100 cm

4. AC + CP = 141.42 cm

Q. What is the value of perimeter of a triangle, if the inradius is 5 cm and area is 10 sq. cm?

1. 4 cm
2. 2 cm
3. 6 cm
4. 5 cm

Q.

The most common, flagellated asexual spores of algae are called

1. oospore
2. aplanospores
3. zoospores
4. zygospore

Q. Which of the following undergoes meiosis in algae?

1. Zoospore
2. Zygote
3. Aplanospore
4. Algae never undergo meiosis as they are haploid

Q. Asexual reproduction by non-motile spores is seen in

1. Ectocarpus
2. Porphyra
3. Chlamydomonas
4. kelps

Q. Zoospores are formed inside special structures called zoosporangium.

1. False
2. True

Q. All the offspring formed during fragmentation and zoospore formation are identical to the parent algae.

1. False
2. True

Q. Choose the false statement.

1. Spores of class Rhodophyceae do not have flagella
2. Spores of Phaeophyceae - are round in shape
3. Spores of class Chlorophyceae have many flagella
4. Spores of class Phaeophyceae have laterally attached flagella

Q. Choose the wrong statement.

1. Spore formation is a type of vegetative reproduction.
2. During fragmentation the plant thallus breaks into many fragments and each fragment grows into a new offspring.
3. Fragmentation is a type of vegetative reproduction.
4. Generally filamentous algae undergo fragmentation.