Biology: CUET Mock Test - 2 - Class 12 MCQ

Zoophily is defined as pollination via animals. Insects are the most important animal pollinators. Birds, snails, bats, etc. also play an important role. Some lizards, lemurs, etc. also have proven to be important for pollination.

The areas on the exterior of the seminiferous tubules called interstitial spaces, contain small blood vessels and small clusters of big, polygonal cells called Leydig cells or interstitial cells. Leydig cells synthesize and secrete hormones (testicular) called androgens.

The female external genitalia include mons pubis, labia majora, labia minora, hymen and clitoris. The vagina is a fibro-muscular tube measuring 7.5-10cm in length, extending from the cervix of the uterus to the vestibule on the outer side.

A functional mammary gland is distinctive of all female mammals. The mammary glands are paired structures (breasts) that contains the glandular tissue and variable amounts of fat.

Zoophilous flowers are often adapted to be pollinated by particular type of animals. Bees and butterflies pollinate the maximum number of flowering plants. The two common families pollinated by them are Asteraceae and Lamiaceae.

The Correct Answer is A: testosterone

Testosterone is a hormone that plays a crucial role in the growth, maintenance, and functioning of secondary sex organs in males. It is primarily produced by the Leydig cells in the testes.

Testosterone is responsible for the development of male secondary sexual characteristics such as the growth of facial and body hair, deepening of the voice, and enlargement of the testes and penis during puberty. It also promotes the growth and maintenance of other reproductive structures such as the seminal vesicles, which produce seminal fluid, and the prostate gland.

Additionally, testosterone is involved in regulating sexual function and libido, sperm production, and the overall well-being and vitality of males. It influences the maintenance of muscle mass and bone density and plays a role in red blood cell production.

In summary, testosterone is essential for the growth, maintenance, and functioning of secondary sex organs and is vital for the overall development and reproductive health of males.

Mons pubis is a cushion of fatty tissue covered by skin and pubic hair. The female external genitalia include mons pubis, labia majora, labia minora.

The mammary glands are made of glandular tissue. The glandular tissue of each breast is divided into 15-20 mammary lobes containing clusters of cells called alveoli.

Entomophily is a common type of zoophily wherein the pollen grains of mature anthers of a flower are transferred to a mature stigma of another flower through insects like beetles, moths, butterflies, wasps, bees, etc.

A 40cm long vas deferens emerges from the cauda epididymis on each side and leaves the scrotal sac and enters the abdominal cavity through the inguinal canal.

The clitoris is a tiny finger-like structure which lies at the upper junction of the two labia minora above the urethral opening. It is erectile and highly sensitive and is equivalent to the male penis.

The cells of alveoli secrete milk, which is stored in the cavities (lumens) of alveoli. Bile is secreted by the liver that helps digest lipids. Sweat is secreted by the sweat glands to maintain body temperature.

Other parts of the flower become showy when petals aren’t attractive. Bougainvillea is known for its showy bracts, leaves in Euphoria pulcherrima, stamens in mimosa, spathes in aroids, etc.

The vas deferens loops over the urinary bladder where it is joined by duct from the seminal vesicle to form the ejaculatory duct. The end of the vas deferens dilates to form a spindle-like ampulla for temporary storage of sperm.

Bulbils, also called vegetative propagation by flower buds is not an example of sub aerial vegetative propagation. It produces multicellular fleshy buds that give rise to new plants. Example, Agave.

The alveoli open into mammary tubules. The tubules of each lobe join to form a mammary duct. Breasts are made up of glandular tissue.

Flowers attract insects in different ways. One way is by producing a smell. Pleasant odors and fragrances attract bees and butterflies. Foul smells attract flies and beetles. Rafflesia produces a foul smell which attracts flies. This is also known as the fly trap mechanism.

The vas deferens is lined with pseudostratified columnar epithelium. The free end of its cells also bears stereocilia. The muscular wall of the vas deferens is formed of smooth muscles, and the latter’s peristaltic contractions propel the sperms through the vas deferens.

The Bartholin’s glands or Vestibular glands are two bean shaped glands, one on either side of the vaginal orifice. These glands secrete a clear, viscous fluid under sexual excitement.

The alveoli opens into mammary tubules. The tubules of each lobe join to form a mammary duct. Several mammary ducts join to form a wider mammary ampulla which is connected to lactiferous duct through which milk is sucked out.

Edible pollens are produced by Rosa, Clematis, Magnolia, etc. Studies show that pollen grains are highly nutritive. They have even claimed to cure many health issues.

External opening of the urethra is called urethral meatus. The male urethra provides a common pathway for the flow of urine called semen. It is much longer in male than in the female, measuring about 15-29 cm.

The hymen, the thin membranous diaphragm at the vaginal orifice, is often torn during the first coitus (intercourse). Hymen maybe torn in other ways too, like sports, a disease, sudden jolt, etc. In some females, the hymen persists even after intercourse. Hence, presence or absence of hymen is an unreliable indicator.

Parthenogenesis is a process of reproduction where the ovum is unfertilized. In case of bees the eggs are haploid which subsequently makes the male bee haploid. It is a type of asexual reproduction. This type of reproduction takes place in lower plants like aphids.

Some flowers provide safe place to insects for laying eggs, e.g., Yucca, Amorphophallus. Amorphophallus contains 200 species. The tallest flower belongs to Amorphophallus (six feet tall).

Syngamy is the process of fusion of a haploid male(n) and a haploid female(n) gamete. On fusion, the zygote or the egg formed is diploid(2n). Often this process is also known as fertilization.

The labia majora (Large Lips) are fleshy folds of skin containing sweat and sebaceous glands, which extend down from the mons pubis and surround the vaginal opening.

Colostrum is the yellow fluid that appears at the beginning of breast feeding. It is highly nutritious for the baby as that is the only thing that provides protection for the baby (rich in antibodies).

It is reproduction without fertilization. This means, the egg or ovum or the female gamete is not fertilized by the male gamete. The offspring hence born is haploid. Since there is no fertilization involved, it is called as virginal reproduction or virgin birth.

he second part is the membranous urethra which is situated behind the lower part of the pubic symphysis. The membranous urethra is the smallest urethra.