Secondary succession takes place on/in
bara rock
degraded forest
newly created pond
newly created pond
The mass of living material at a tropic level at a particular time is called
gross primary productivity
standing state
net primary productivity
net primary productivity
In an ecosystem the rate of production of organic matter during photosynthesis is termed as
net primary productivity
gross primary productivity
secondary productivity
secondary productivity
Which of the following represents the correct combination without any exception?
Characteristic | Class |
Mammary gland; hair on body; pinnae; two pairs of Limbs | Mammalia |
Characteristic | Class |
Mouth ventral, gills without operculum; skin with placoid scales; persistent notochord | Chondricht hyes |
Characteristic | Class |
Sucking and circular mouth; jaws absent, integument without scales; paired appendages | Cyclostomata |
Characteristic | Class |
Sucking and circular mouth; jaws absent, integument without scales; paired appendages | Cyclostomata |
Select the correct option:
Column I | Column II | |
A | Synapsis aligns homologous chromosomes | 1. Anaphase-II |
B | Synthesis of RNA and protein | 2. Zygotene |
C | Action of enzyme recombinase | 3. G2-phase |
D | Centromeres do not separate but chromatids move towards opposite poles | 4. Anaphase-I |
5. Pachytene |
Capacitation refers to changes in the
Sperm before fertilization
Ovum before fertilization
Ovum after fertilization
Ovum after fertilization
Which of these is not an important component of initiation of parturition in humans?
Increase in oestrogen and progesterone ratio
Synthesis of prostaglandins
Release of oxytocin
Release of oxytocin
Which of the following viruses is not transferred through semen of an infected male?
Hepatitis B virus
Human immunodeficiency virus
Chikungunya virus
Chikungunya virus
Which of the following cells during gametogenesis is normally dipoid?
Primary polar body
Spermatid
Spermatogonia
Spermatogonia
C.
Spermatogonia
Spermatogonium are produced from the undifferentiated primordial germ cells which divide continuously by mitosis to form diploid cells, i.e. primary spermatocyte. These are the precursors of sperms, (the haploid cells). Primary polar body, secondary polar body (in oogenesis) are produced after first meiotic division as haploid cells. Spermatids are haploid cells produced by second meiotic division of secondary spermatocytes (n).
Hysterectomy is surgical removal of
prostate gland
vas deference
vas deference