Which of the following is not a function of the skeletal system?
Production of erythrocytes
Storage of minerals
Production of body heat
Production of body heat
C.
Production of body heat
Production of body heat is the function of muscles. The contraction of muscle produce heat, which keeps the body warm during the winters.
Read the different components from I to IV in the list given below and tell the correct order of the components with reference to their arrangement from outer side to inner side in a woody dicot stem:
(a) Secondary cortex
(b) Wood
(c) Secondary phloem
(d) Phellem
The correct order is
(c), (d), (b), (a)
(a), (b), (d), (c)
(d), (a), (c), (b)
(d), (a), (c), (b)
C.
(d), (a), (c), (b)
The correct order of arrangement of the given components from outside to inside in a woody dicot stem is as follows:
Phellem Secondary cortex
Secondary phloem
wood
TS of a typical dicot stem showing secondary growth
The imperfect fungi which are decomposer of litter and help in mineral cycling belong to
Deuteromycetes
Basidiomycetes
Phycomycetes
Phycomycetes
A.
Deuteromycetes
The imperfect fungi which are decomposers of litter and help in mineral cycling belong to Deuteromycetes. They are fungi which do not fit into the commonly established taxonomic classification of fungi. They include all those fungi in which the perfect stage(sexual stage) is not reported.
Chromatophores take part in
Photosynthesis
Growth
Movement
Movement
A.
Photosynthesis
Chromatophores are found in members of phototrophic bacteria. They contain bacteriochlorophyll pigments and carotenoids and take part in photosynthesis. In purple bacteria, such as Rhodospirillum rubrum, the light-harvesting proteins are intrinsic to the chromatophore membranes. However, in green sulphur bacteria, they are arranged in specialised antenna complexes called chlorosomes.
Column-I |
Column-II |
Thylakoids | Dis-shaped sacs in Golgi apparatus C |
Cristae | Condensed structure of DNA |
Cisternae | flat membranous sacs in stroma |
Chromatin | Infoldings mitochondrial |
B.
CodesThe wheat grain has an embryo with one large, shield-shaped cotyledon known as
Epiblast
Coleorrhizia
Scutellum
Scutellum
C.
Scutellum
The grain of wheat, maize or rice is a caryopsis. The embryo in such grains lies laterally near the base of the grain. The embryo consists of an upper large, shield-shaped cotyledon known as scutellum. The scutellum is closely pressed against the endosperm and helps in the translocation of nutrients from endosperm to the growing embryo at the time of germination and seedling growth.
Which of the .following structures is not found in a prokaryotic cell?
Nuclear envelope
Ribosome
Mesosome
Mesosome
A.
Nuclear envelope
In a prokaryotic cell, nuclear envelope is not found. It means genetic material (DNA) is not enclosed by any envelope and lies in direct contact with the cytoplasm.
Which one of the following hormones is not involved in sugar metabolism?
Cortisone
Aldosterone
Insulin
Insulin
B.
Aldosterone
Aldosterone is not involved in sugar metabolism. It is a steroid hormone (mineralocorticoid) produced by the outer section(zona glomerulosa) of the adrenal cortex in the adrenal gland. It plays a central role in the adrenal gland. It plays a central role in the regulation of blood pressure mainly by acting on the distal tubules and collecting ducts of the nephron, increasing reabsorption of ions and water in the kidney, to cause the conservation of sodium, secretion of potassium, increase in water retention and decrease in blood pressure and blood volume.
Which of the following joints would allow no movement?
Fibrous joint
Cartilaginous joint
Synovial Joint
Synovial Joint
A.
Fibrous joint
Fibrous joints are immovable joints in that occur between the bones of the cranium and in the tooth sockets. They do not allow movement because the bones are held firmly together by bundles of strong white collagen fibres. The immovable joints are often known as the sutures. The periosteum that covers the bones dips between them as a septum
During biological nitrogen fixation inactivation of nitrogenase by oxygen poisoning is prevented by
Leghaemogolobin
Xanthophyll
Carotene
Carotene
A.
Leghaemogolobin
During biological nitrogen fixation, inactivation of nitrogenase by oxygen poisioning is prevented by leghaemoglobin.
It is a red-pigment that is filled outside the peribacteroid space in the cytosol of nodule cells. It has the ability to combine very rapidly with oxygen and thus acts a very efficient O2 scavenger.