The sex of a fetus can be determined by examining the cells of the amniotic fluid for the presence of:

In which organisms are macrolecithal eggs found?

Choose the correct option regarding the statements provided:
$(1)$ The process of fusion of a sperm with an ovum is called fertilization.
$(2)$ $LH$ surge induces the rupture of the Graafian follicle.
$(3)$ An $8$-celled embryo is called a morula.
$(4)$ The length of the fallopian tube is $8-10 \, cm$.

Which of the following pairs is correctly matched?

Which of the following statements are correct regarding the female reproductive cycle?
$A$. In non-primate mammals,cyclical changes during reproduction are called the oestrus cycle.
$B$. The first menstrual cycle begins at puberty and is called menopause.
$C$. Lack of menstruation may be indicative of pregnancy.
$D$. Cyclic menstruation extends between menarche and menopause.
Choose the most appropriate answer from the options given below.

Describe the location and function of the Bulbourethral gland and Corpus luteum.