Delicate hair-like feathers which remain sparsely distributed over the body are
coverts
filoplumes
plumules
remiges
Which of the following postulates is related with Neo-Darwinism?
Mutations are believed to help form new species
It incorporates isolation as an essential component of evolution.
It can explain the occurrence of unchanged forms over millions of years.
All of the above
A person who shows unpredictable moods, outbursts of emotions, quarrelsome behaviour and conflicts with others is suffering from
borderline personality disorder (BPD)
mood disorder
addictive disorder
schizophrenia
In humans at the end of first meiotic division, the male germ cells differentiate into the
primary spermatocytes
secondary spermatocytes
spermatids
spermatogonia
B.
secondary spermatocytes
At sexual maturity, the undifferentiated primordial germ cells divide several times by mitosis to produce a large number of spermatogonia. Each spermatogonium then grows to a large primary spermatocyte. Each primary spermatocyte undergoes two successive divisions, called maturation divisions. The first maturation division is reductional or meiotic. Hence, the primary spermatocyte divides into the haploid daughter cells called secondary spermatocytes.
Contraceptive oral pills help in birth control by
killing the sperms in uterus
preventing implantation
preventing ovulation
both (b) and (c)
Which of the following species has the chromosome complement similar to that of Triticum aestivum ?
Zea mays
Secale cereale
Gossypium
Aegilops
Eugenics is the branch concerned with
improving the quality of human race by symptomatic treatment of genetic diseases.
improving the quality of human populations by the application of genetic principles
improving the quality of human race by providing best suitable environment.
none of the above
What is incorrect about the following figure representing DNA replication?
The direction of DNA replication in strand (i)
The direction of DNA replication in strand (ii)
Discontinuous replication of strand (i)
Discontinuous replication of strand (ii)