2022Flame Institute

When three Spirogyra filaments are participating in conjugation, the possibilities are that

(a) The middle one may be female and outer ones are male (b) The middle one may be male and outer ones are female (c) Both (a) and (b) (d) None of the above Ans. c (5)

Pyrenoid is found in one of the following part of Spirogyra

(a) Cytoplasm (b) Cell wall (c) Chloroplast (d) Nucleus Ans. c (6)

The sexual reproduction in Spirogyra is

(a) Oogamous (b) Anisogamous (c) Cleistogamous (d) None of the above Ans. d (3)

Spirogyra differs from moss protonema in having

(a) Pyrenoid (b) Branched filament (c) Discoid chloroplast (d) Rhizoidal branches Ans. a (5)

Sexual reproduction in which cells of two different Spirogyra filaments conjugate is known as

(a) Lateral conjugation (b) Scalariform conjugation (c) Parthenocarpy (d) Azygospory Ans. b (7)

In Spirogyra meiosis occurs in

(a) The developing zygospore (b) During conjugation process (c) During vegetative reproduction (d) During gamete formation Ans. a (22)

Chloroplasts of Spirogyra have

(a) Smooth margin (b) Wavy margin (c) Smooth or wavy margin (d) None of the above Ans. b (5)

Pond silk’ is the common name of

(a) Ulothrix (b) Spirogyra (c) Vaucheria (d) Oedogonium Ans. b (10)

Which structure of Spirogyra is flagellated

(a) Physiologically different male gametes (b) Physiologically different female gametes (c) Zygospore (d) None of the above Ans. d (9)

Maximum number of chloroplasts recorded in Spirogyra is

(a) 6 (b) 12 (c) 20 (d) 16 Ans. d (12)

Filaments of Spirogyra are

(a) Uniseriate and unbranched (b) Uniseriate and branched (c) Multiseriate and unbranched (d) Multiseriate and branched Ans. a (23)

Cells of Spirogyra are

(a) Uninucleate (b) Binucleate (c) Multinucleate (d) None of the above Ans. a (6)

Three rods each of length L and mass M are placed along X, Y and Z-axes in such a way that one end of each of the rod is at the origin. The moment of inertia of this system about Z axis is

(a) 2ML2/3 (b) 4 ML2/3 (c) 5 ML2/3 (d) ML2/3 Ans. a (12)

The ratio of the K.E. required to be given to the satellite to escape earth’s gravitational field to the K.E. required to be given so that the satellite moves in a circular orbit just above earth atmosphere is

(a) One (b) Two (c) Half (d) Infinity Answer: b (4)

Most primitive members of the plant kingdom are

(a) Thallophytes (b) Bryophytes (c) Pteridophytes (d) Gymnosperms Ans. a (47)

Spirogyra is a

(a) Fresh water and free floating alga (b) Marine and free floating alga (c) Fresh water and locomotory alga (d) None of the above Ans. a (6)

19. Let be the moment of inertia of an uniform square plate about an axis AB that passes through its centre and is parallel to two of its sides. CD is a line in the plane of the plate that passes through the centre of the plate and makes an angle θ with AB . The moment of inertia of the plate about the axis CD is then equal to

(a) l (b) l sin2θ (c) l cos2θ …

Moment of inertia of a uniform circular disc about a diameter is I. Its moment of inertia about an axis perpendicular to its plane and passing through a point on its rim will be

(a) 5 I (b) 6 I (c) 3 I (d) 4 I Ans. b (6)

14. Five particles of mass = 2 kg are attached to the rim of a circular disc of radius 0.1 m and negligible mass. Moment of inertia of the system about the axis passing through the centre of the disc and perpendicular to its plane is

(a) 1 kg m2 (b) 0.1 kg m2 (c) 2 kg m2 (d) 0.2 kg m2 Ans. b (11)

An astronaut orbiting the earth in a circular orbit 120 km above the surface of earth, gently drops a spoon out of space-ship. The spoon will

(a) Fall vertically down to the earth (b) Move towards the moon (c) Will move along with space-ship (d) Will move in an irregular way then fall down to earth Answer: c (3)

Meiotic division in zygote takes place in

(a) Thallophyta (b) Angiosperms (c) Gymnosperms (d) Pteridophyta Ans. a (6)

A satellite which is geostationary in a particular orbit is taken to another orbit. Its distance from the centre of earth in new orbit is 2 times that of the earlier orbit. The time period in the second orbit is

(a) 4.8 hours (b) 48√2 hours (c) 24 hours (d) 24 √2 hours Answer: b (3)

80. The extension of a wire by the application of load is 3 mm. The extension in a wire of the same material and length but half the radius by the same load is

(a) 12 mm (b) 0.75 mm (c) 15 mm (d) 6 mm Answer-a (37)

The giant algae or sea weeds belong to class

(a) Phaeophyceae (b) Rhodophyceae (c) Chlorophyceae (d) Xanthophyceae Ans. a (8)

In the Chlorophyta, the reserve food of protein surrounded by starch, form a compact body termed

(a) Paramylum (b) Pyrenoid (c) Volutin (d) Eye spot Ans. b (4)

Most important alga in research centres is

(a) Mycoplasma (b) Spirogyra (c) Chlorella (d) Blue-green algae Ans. c (9)

Algae differ from Bryophyta in possessing

(a) Naked sex organs (b) Sex organs covered with sterile covering (c) Chlorphylls a andb (d) Aerobic respiration Ans. a (8)

Sex organs of thallophytes are generally

(a) Unicellular (b) Multicellular surrounded by a sterile jacket (c) Multicellular but not surrounded by any jacket (d) Unicellular with a sterile jacket Ans.a (10)

Plants manufacturing their own food are called

(a) Epiphytes (b) Parasites (c) Saprophytes (d) Autotrophs Ans. d (8)

Sexual reproduction in algae results in the formation of

(a) Oospore (b) Zoospore (c) Zygote (d) Zygospore Ans. d (14)

Chlamydomonas does not occur in

(a) Fresh water (b) Pond and lake (c) River (d) Ocean Ans. d (7)

Consider a satellite going round the earth in an orbit. Which of the following statements is wrong

(a) It is a freely falling body (b) It suffers no acceleration (c) It is moving with a constant speed (d) Its angular momentum remains constant Answer: b (7)