Biology Test 150

India has four biodiversity hotspots, i.e., Eastern Himalayas, Western Himalayas, Western Ghats and Andaman and the Nicobar Islands.

A biodiversity hotspot is a biogeographic region with significant levels of biodiversity that is threatened by human habitation.

Hence, the correct option is (C).

A germ layer is a primary layer of cells that forms during embryonic development. The three germ layers invertebrates are particularly pronounced, however, all eumetazoans (animals more complex than the sponge) produce two or three primary germ layers. Some animals, like cnidarians, produce two germ layers (the ectoderm and endoderm) making them diploblastic. Other animals such as chordates produce a third layer (the mesoderm) between these two layers, making them triploblastic. Germ layers eventually give rise to all of an animal’s tissues and organs through the process of organogenesis.

Hence, the correct option is (A).

Contraception aims to prevent pregnancy. A woman can get pregnant if a man's sperm reaches one of her eggs. Contraception tries to stop this from happening by keeping the egg and sperm apart, stopping egg production. Oral contraceptives (birth control pills) are used to prevent pregnancy.

Estrogen and progestin are two female sex hormones. Combinations of estrogen and progestin work by preventing ovulation (the release of eggs from the ovaries).

Hence, the correct option is (D).

Rice bean (Vigna umbellata) is a tropical to temperate grain legume primarily grown for food, especially in Asia. Rice bean seeds and vegetative parts are also used for fodder. Vigna umbellata is a short-lived perennial legume usually grown as an annual. It has a very variable habit: it can be erect, semi-erect, or twining. It is usually 30-100 cm in height but can grow up to 200 cm.

Hence, the correct option is (C).

The atmospheric scientist Paul Crutzen introduced the term "Anthropocene" in the mid-1970s. The term is sometimes used in the context of pollution emissions that are produced from human activity since the start of the Agricultural Revolution but also applies broadly to all major human impacts on the environment. 

Hence, the correct option is (C).

Animal cells also have a centrosome and lysosomes. The centrosome has two bodies, the centrioles, with an unknown role in cell division. Lysosomes are the digestive organelles of animal cells. Plant cells have a cell wall, chloroplasts, and a central vacuole.

Hence, the correct option is (B).

Phosphorus is important in plant bioenergetics and is needed for the conversion of light energy to chemical energy during photosynthesis. Phosphorus can also be used to modify the activity of various enzymes by phosphorylation and can be used for cell signaling.

Hence, the correct option is (A).

Archaebacteria are a type of single-cell organism which are so different from other modern life-forms that they have challenged the way scientists classify life. Another remarkable trait of archaebacteria is their ability to survive in extreme environments, including very salty, very acidic, and very hot surroundings.

Bacteria and Archaea differ in the lipid composition of their cell membranes and the characteristics of the cell wall. Bacterial cell walls contain peptidoglycan. Archaean cell walls do not have peptidoglycan, but they may have protein-based cell walls.

Hence, the correct option is (C).

A Southern blot is a method used in molecular biology for the detection of a specific DNA sequence in DNA samples. Southern blotting combines the transfer of electrophoresis-separated DNA fragments to a filter membrane and subsequent fragment detection by probe hybridization.

The correct sequence will be- ii, vi, v, iii, i, and iv
Hence, the correct option is (D).

Phytoremediation is a bioremediation process that uses various types of plants to remove, transfer, stabilize, and/or destroy contaminants in the soil and groundwater. There are several different types of phytoremediation mechanisms.

Hence, the correct option is (C).