Which one onf the following groups of animals is bilaterally symmetrical and triploblastic?
Coelenterates (cnidarians)
Aschelminthes (roundworms)
ctenophores
ctenophores
B.
Aschelminthes (roundworms)
Aschelminthes are bilateral symmetrical and triploblastic animals, eg, Ascaris.
Coelenterates are radially symmetrical and diploblastic animals, eg, Obelia.
Ctenophores are biradial symmetrical and diploblastic animals, eg, Ctenoplana.
Sponges are asymmetrical or radially symmetrical and diploblastic animals, eg, sycon.
Which one of the following has haplontic life cycle?
Funaria
Polytrichum
fully developed foetus and placenta
fully developed foetus and placenta
C.
fully developed foetus and placenta
Ustilago has the haplontic life cycle. In their sexual phase, the only zygospore is diploid structure. All others are haploid, such a sexual cycle is termed as haploid or haplontic.
Mannitol is the stored food in of
Chara
Porphyra
Fucus
Fucus
C.
Fucus
Fucus belongs to class-Phaeophyceae, in which reserve food is found in form of laminarin, mannitol and oil.
Chara belongs to class- Chlorophyceae, in which reserve food is found in form of starch and oil.
Porphyra and Grachillaria belong to class- Rhodophyceae, in which reserve food is found in form of floridean starch and Galactan- SO4 polymers
Elbow joint is an example of
pivot joint
hinge joint
gliding joint
gliding joint
B.
hinge joint
In hinge joint, the convex surface of one bone fits into the concave surface of another bone. eg, knee elbow and interphalangeal joints.
Pivot joint, one bone is fixed and second articulated, eg, atlas and axial of skull rotate with axis vertebra.
Gliding joints primarily permit side-by-side and back and forth gliding movements, eg, intercarpal joints and intertarsal joints.
In ball and socket joint, a ball of one bone articulates in sockets of another bone, eg, head of the humerus and glenoid cavity of the pectoral girdle.
Which one of the following pairs of food components in humans reaches the stomach totally undigested?
Protein and starch
Starch and fat
Fat and cellulose
Fat and cellulose
C.
Fat and cellulose
In humans, starch is digested in the buccopharyngeal cavity. Cellulose is not digested in the humans because cellulose contains β -1, 4-linkages and vertebrates themselves do not possess any enzymes capable of hydrolyzing β-1, 4 - linkages. Protein is digested in stomach and fat in the small intestine.Thus in the given options, fat and cellulose reach totally undigested in the stomach of humans
The correct sequence of plants in a hydrosere is
Oak → Lantana → scirpus→Pistia→Hydrilla→Volvox
Volvox → Hydrilla → Pistia → Scirpus → Lantana → Oak
Pista → Volvox → Scirpus → Hydrilla → Oak → Lantana
Pista → Volvox → Scirpus → Hydrilla → Oak → Lantana
B.
Volvox → Hydrilla → Pistia → Scirpus → Lantana → Oak
The various stages in a hydrosere are well studied in ponds. Pools or lakes. The various stages of hydrosere are:
Phytoplankton stage, eg, some blue-green algae, green algae (volvox), diatoms and bacteria, etc.
Rooted submerged stage, eg Hydrilla Vallisneria, etc.
Floating stage, eg, Nelumbo, Nymphaea, etc. Some free-floating species are pisita, Azolla, Lemna, etc.
Red -swamp stage, eg, species of Cyperaceae and Gramineae.
Forest stage, eg, Tropical rain forests, mixed forests of Almus, Acer, Quercus (oak), tropical deciduous forests.
A change in the amount of yolk and its distribution in the egg will effect
formation of a zygote
the pattern of cleavage
number of blastomeres produced
number of blastomeres produced
B.
the pattern of cleavage
The mode of cleavage is determined by the amount of yolk and its distribution.
(I) Holoblastic - The cleavage, in which the segmentation lines pass through the entire egg, dividing it completely, eg, frog, human egg, etc.
(II) Meroblastic -The lines of segmentation do not completely pass through the egg and remain confined to a part of the egg, eg , insects, birds, reptiles.
Stroma in the chloroplasts of higher plants contains
light -independent reaction enzymes
Light -dependent reaction enzymes
ribosomes
ribosomes
A.
light -independent reaction enzymes
In higher plants, enzymes for light-independent reactions (dark reactions) are present in the stroma of chloroplasts.
The light-dependent reaction occurs in grana of the chloroplast.
Ribosomes are necessary for protein synthesis.
Chlorophyll is green photosynthetic pigment found in chloroplasts.
The epithelial tissue present on the inner surface of bronchioles and fallopian tubes is
cuboidal
glandular
ciliated
ciliated
C.
ciliated
Giliated columnar epithelium lines respiratory tract (lower end of bronchi) fallopian tubes, ventricles of brain (ependyma) central canal of spinal cord, etc. Cuboidal epithelium occurs in certain parts of nephrons of the kidneys.
Glandular epithelium are specialised for secretory activities eg, unicellular multicellular, exocrine, endocrine, heterocrine glands, etc.
Squamous epithelium forms lining of blood vessels, lymph vessel, heart, peritoneum, pleura, Bowman's capsule, etc,
Uric acid is the chief nitrogenous component of the excretory products of
man
earthworm
cockroach
cockroach
C.
cockroach
Cockroach excretes uric acid as the chief nitrogenous excretory product.
Man excretes urea as the chief nitrogenous excretory product.
Earth warm excretes 40%, urea, 20% ammonia and 40% amino acids.
Frog excretes urea as the chief nitrogenous product.