BIO 101 | Study Mode

Join Discuss Share to WhatsApp
Question 281
A
sacral nerves
B
3rd, 7th, 9th and 10th cranial nerves
C
thoraco-lumbar nerves
D
cervical nerves.
Explanation
Sympathetic nervous system forms a part of autonomic nervous system that consists of nerves which connect the visceral receptors and effectors with the central nervous system through the crania and spinal nerves. Sympathetic nerves arise from thoracolumbar nerves.

Correct option: C
Join Discuss Share to WhatsApp
Question 282
A
one single opening of the digestive canal
B
cilia on the surface to create water current
C
radial symmetry
D
asymmetrical body.
Explanation
The organisms attached to the substratum possess radial symmetry in all vertical planes. All the animals belonging to cnidaria (e.g. jellyfish) and echinodermata (e.g. starfish) are radially symmetrical and typically sessile in their adult form. In radial symmetry the parts in an organ or organism when cut through the centre in any direction produces two halves that are mirror images of each other.

Correct option: C
Join Discuss Share to WhatsApp
Question 283
A
osmoregulation
B
reproduction
C
locomotion
D
digestion of food.
Explanation
The function of contractile vacuole is osmoregulatory. Water in freshwater protozoa enters the organism by endosmosis and during feeding. If the organism does not possess a mechanism to get rid of this excess water, it will swell to the point of rupture and dissolution. The mechanism which is assumed to effect water regulation is the contractile vacuole. The vacuole periodically increases in volume (diastole) to get filled with water and contracts (systole) to discharge its water content to the surrounding environment.

Correct option: A
Join Discuss Share to WhatsApp
Question 284
A
mollusca
B
acanthocephala
C
cestoda
D
chordata.
Explanation
The term metamerism refers to a linear repetition of parts in an animal body. It occurs in three highly organized phyla: Annelida, Arthropoda and Chordata. Each segment is called a metamere, or somite. Segmentation often affects both external and internal structures. Such a condition is called metameric segmentation. <br /> In chordates, the segmentation is apparent only in the embryonic stage. In the adult chordates, segmentation is visible in the internal structures, such as vertebrae, ribs, nerves and blood vessels. Other animals have unsegmented bodies.

Correct option: D
Join Discuss Share to WhatsApp
Question 285
A
Euglena
B
Paramecium
C
bacteria
D
Mycoplasma.
Explanation
Euglena possesses the characteristics of both plant and animal. It has chlorophyll, thus it is autotrophic like plants. In contrast to this, it has flagellated locomotion like animals.

Correct option: A
Join Discuss Share to WhatsApp
Question 286
A
folding of inner walls
B
gastro-vascular system
C
reproduction
D
porous walls.
Explanation
The body wall of sponges encloses a large cavity, the spongocoel and in most cases also contains in its thickness numerous small cavities, the canals. Either the spongocoel or certain canals are lined by choanocytes with flagella. <br />The ceaseless beating of flagella maintains a steady current of water through the canals in the sponge body. The current of water enters through small pores, the dermal ostia, perforating the porocytes and, after passing through various canals, enters the spongocoel, and finally leaves through a larger aperture, the osculum, or apertures, the oscula. <br />All the cavities in a sponge body are intercommunicating, and are collectively referred to as the canal system. The current of water that flows through the canal system brings in food and oxygen, and carries away carbon dioxide and nitrogenous waste materials. Thus, the canal system helps the sponge in nutrition, respiration and excretion.

Correct option: D
Join Discuss Share to WhatsApp
Question 287
A
they undergo no moulting
B
they have seven cervical vertebrae
C
they are carnivores
D
they have ventral nerve cord.
Explanation
Mammals do not undergo moulting. Moulting is usually exhibited by invertebrates. In many vertebrate species, cervical vertebrae are variable in number, however almost all mammals have seven cervical vertebrae including those with short neck such as elephants or whales and those with very long necks, such as giraffes. But there are a few exceptional cases in which there are nine cervical vertebrae in mammals. Mammals have dorsal nerve cord. All the mammals are not carnivorous; they may be herbivorous, carnivorous and omnivorous also.

Correct option: A
Join Discuss Share to WhatsApp
Question 288
A
nematoblasts of Hydra
B
flame cells of Planaria
C
gills of Prawn
D
trachea of insects.
Explanation
Analogous organs are organs of very disparate organisms and are superficially similar but have evolved from vastly different origins. They have same function but different structure. The nephridia in earthworm are analogous to flame cells of Planaria since both of them have excretory functions. Nematoblasts of Hydra are organs of locomotion, food capture and anchorage. Gills and trachea are organs of respiration in prawn and insects respectively.

Correct option: B
Join Discuss Share to WhatsApp
Question 289
A
shark
B
Rana
C
pigeon
D
whale.
Explanation
Pneumatic bone is present in pigeon to keep the bones light weight because the pigeon has to fly. Pneumatic bone has a hollow cavity, which makes k light.

Correct option: C
Join Discuss Share to WhatsApp
Question 290
A
body wall and ectoderm
B
ectoderm and endoderm
C
mesoderm and body wall (endoderm)
D
mesoderm and ectoderm.
Explanation
Coelorn is a fluid-filled cavity that forms the main body cavity of vertebrate and most invertebrate animals. It is found between mesoderm and body wall (endoderm).

Correct option: C

Try this quiz in in E-test/CBT Mode
switch to BIO 101 in CBT Mode

Previous Page Next Page