Biology MCQs

Notes:
Arthropoda is the largest phylum of animal kingdom because around 2/3rd of all the named species on Earth belong to this phylum.
Ants, mosquitoes, flies, cockroaches, shrimp, crabs, spiders, scorpions etc. are examples of arthropods. There are three main classes of arthropods as follows:

• Insects: This includes mosquitoes, cockroaches, ants, flies, bees, moths, grasshoppers, beetles and butterflies
• Crustaceans: This includes crabs, lobsters, shrimp and barnacles
• Arachnids: This includes scorpions, spiders and mites

Further, a few other classes are onychophorans (velvet worms), diplopods (millipedes) and chilopods (centipedes).

Notes:
The hard part of a stem of a plant is because of Xylem. Stem supports leaves, flowers and fruits. It also transports fluids between the roots and the shoots in the xylem and phloem, stores nutrients, and produces new living tissue.

Notes:
Potassium, Sodium, Magnesium, Calcium are required in maximum quantities in a living organism.

Notes:
The insect “Apis mellifera” is commonly known as the honey bee. The Western honey bee is the most common of the 7–12 species of honey bees worldwide. The genus name “Apis” is Latin for “bee”, and “mellifera” is Latin for “honey-bearing” or “honey carrying”.  Honey bees are known for their role in pollination. They were domesticated for honey production and crop pollination. Honey bees produce honey, wax, propolis, and royal jelly.  Honey bees are red/brown with black bands and orange yellow rings on their abdomen. They have hair on their thorax and less hair on their abdomen. The workers and queens have stingers, whereas the drones are stingless.

Notes:
Meg-1 gene was developed in Maize. It is an imprinted gene which finds expression only from maternal chromosomes which regulates the transfer of nutrients from the plant to the seed.

Notes:
B is the correct answer. 

Notes:
In humans, fertilization normally occurs in the fallopian tube. The ovary is the female gonad that contains the eggs. The uterus is the organ that houses the developing embryo. The placenta is the structure that nourishes the embryo.

Notes:
Dermatogen is the outer primary meristem of a plant or plant part that according to the histogen theory gives rise to epidermis, which is the outermost layer of the skin. Epidermis provides barrier to infection from environmental pathogens.

Notes:
The coconut water from tender coconut that we are familiar with, is nothing but free nuclear endosperm (made up of thousands of nuclei) and the surrounding white kernel is the cellular endosperm. In the most common types of endosperm development, the Primary Endosperm Nucleus (PEN) undergoes successive.

Notes:
The cotton incorporated the cry1Ac gene from the soil bacterium Bacillus thuringiensis (Bt), making the cotton toxic to bollworms. It is a cheaper alternative to Bt cotton hybrid seed.