STD 12 - 11. organisms and populations — Biology STD 12 Science — Question

$(1)$ The process of fusion of a sperm with an ovum is called fertilisation

$(2)$ $LH$ surge induces rupture of graffian follicle

$(3)$ $8$ cells embryo is called morula

$(4)$ Length of fallopian tube is $8-10 \,cm$

$(1)$ Haemophilia is a sex­linked recessive disease.

$(2)$ Down’s syndrome is due to aneuploidy.

$(3)$ Phenylketonuria is an autosomal recessive gene disorder.

$(4)$ Sickle cell anaemia is an $X$-­linked recessive gene disorder.