UP CPMT Botany (2003)

Phytotron is a laboratory with facilities for growing plants under various combinations of strictly controlled environmental conditions.

Producers are the green plants which produce energy through the process of photosynthesis. Solar energy is converted into chemical energy during photosynthesis.

Gases that trap heat in the atmosphere are called greenhouse gases. This gas is mainly carbon dioxide.

Oxygen is the terminal electron acceptor in photosynthesis. In oxygenic photosynthesis, the first electron donor is water that creates oxygen as a waste product.

Horizon O is the top organic layer of soil and is made up mostly of leaf litter and humus (decomposed organic matter).

Transposable elements (TEs), also known as jumping genes or transposons, are sequences of DNA that move (or jump) from one location in the genome to another. Maize geneticist Barbara McClintock discovered TEs in 1940s and for decades thereafter, most scientists dismissed transposons as useless or junk DNA.

Mycorrhiza is a symbiotic association that is composed of a fungus and roots of a vascular plant. It helps in the uptake of nutrition.

Plastocyanin is a copper-containing protein that plays a role in the electron transport process that is associated with photosynthesis. It serves as an electron transfer agent between the cytochrome complex which follows photosystem II and the entry point to photosystem I of the non-cyclic electron transfer process.

Pyruvate is the end product of glycolysis. It is converted to acetyl CoA by pyruvate dehydrogenase complex into acetyl CoA. This finally enters into Kreb's cycle.

Afforestation is the process of planting trees, or sowing seeds, in a barren land that is devoid of any trees to create a forest. It prevents soil erosion.

Decomposers are organisms that break down the dead or decaying organisms and in doing so, they carry out the natural process of decomposition. Like herbivores and predators, decomposers are heterotrophic. They use organic substrates to get their energy, carbon and nutrients for growth and development. Fungus is an example.

Robert Hooke, an English scientist, discovered a honeycomb-like structure in a cork slice using a primitive compound microscope. He only saw cell walls as this was dead tissue. He coined the term 'cell' for these individual compartments he saw.

DNA polymerase is an enzyme that creates DNA molecules by assembling nucleotides, the building blocks of DNA. This enzyme is essential to DNA replication and usually works in pairs to create two identical DNA strands from one original DNA molecule.

ELISA (enzyme-linked immunosorbent assay) is a test that detects and measures antibodies in our blood. This test can be used to determine if you have antibodies that are related to certain infectious conditions, such as AIDS or any viral disease.

Depending on the specific tissue, auxin may promote axial elongation (as in shoots), lateral expansion (as in root swelling) or isodiametric expansion (as in fruit growth).

Transpiration is the process by which moisture is carried through plants from roots to small pores on the underside of leaves, where it changes to vapour and is released to the atmosphere. It is essentially evaporation of water from plant leaves. Thus, humidity decreases the rate of transpiration.

Angiosperms form fruit. Gymnosperms, being the naked seeded trees, do not form a fruit.

Light reaction takes place in the thylakoid discs where water is oxidised and oxygen is released. The electrons that are freed-up from water are transferred to ATP and NADPH. 

Crop rotation is the growing of different crops in succession on a piece of land to avoid exhausting the soil and to control weeds, pests and diseases.

Carbon dioxide is captured in a cycle of reactions known as Calvin cycle or Calvin-Benson cycle. It is also known as C₃ cycle.

Bacteria, being prokaryotic, lack mitochondria.

DNA replication is the biological process of producing two identical replicas of DNA from one original DNA molecule.

Cuscuta (dodder) is a genus of about 100 – 170 species of yellow, orange or red (rarely green) parasitic plants.

Ethylene is an important natural plant hormone that is used in agriculture to force the ripening of fruits.

Osmosis is the spontaneous net movement of solvent molecules through a semi-permeable membrane into a region of higher solute concentration, in the direction that tends to equalise the solute concentrations on the two sides.

Yeast is used for baking and making alcoholic beverages. It has been used in this way since ancient times.

Sieve tubes are connected with perforated sieve plates. They help in the conduction of food downhill.

There is no change in the number of chromosomes in mitosis. Therefore, it is called as equivalent division.

Blue green algae help in nitrogen fixation. Rhizobium is a symbiotic bacterium that is found in the root nodules of leguminous plants. It helps in the nitrogen fixation process.

Fruit flies or the Drosophila is mostly used in genetic experiments.

Correct Answer: blue-green pigment

A meristem is the tissue in most plants that contains undifferentiated cells (meristematic cells). It is found in zones of the plant where growth can take place. Meristematic cells give rise to various organs of the plant and keep the plant growing.

The class Basidiomycetes includes those members that produce their basidia and basidiospores on or in a basidiocarp. Mushroom is an example.

An electron transport chain (ETC) is a series of compounds that transfer electrons from electron donors to electron acceptors via redox (both reduction and oxidation occurring simultaneously) reactions and couple this electron transfer with the transfer of protons (H⁺ ions) across a membrane. Its enzymes are bound to inner mitochondrial membrane.

This is not a law. A sex-determination system is a biological system that determines the development of sexual characteristics in an organism. Most organisms that create their offspring using sexual reproduction have two sexes. Occasionally, there are hermaphrodites in place of one or both sexes.

The response of an organism or its part is termed 'positive' if the growth is towards the stimulus or 'negative' if the growth is away from the stimulus. An example of chemotropic movement can be seen during the growth of the pollen tube, where growth is always towards the ovules.

The number of chromosomes becomes half in gametes due to meiosis. So, the number of chromosome would be 20.

Correct Answer: CO₂ is taken and O₂ is evolved

Binary fission results in the reproduction of a living prokaryotic cell (or organelle) by dividing the cell into two parts, each with the potential to grow to the size of the original.

It was first isolated in 1935 by Teijiro Yabuta and Sumuki, from fungal strains (Gibberella fujikuroi) provided by Kurosawa.

The sugars that are found in nucleic acids are pentose sugars. A pentose sugar has five carbon atoms. In RNA, ribose is found.

Phycoerythrin is a red protein-pigment complex from the light-harvesting phycobiliprotein family. It is present in red algae and cryptophytes, accessory to the main chlorophyll pigments. It is responsible for photosynthesis.

The bark is stripped from the tree, dried and powdered for medicinal uses. The bark is medicinally active and contains a variety of alkaloids, including the antimalarial compound quinine and the antiarrhythmic quinidine.

Denitrification is a microbially facilitated process of nitrate reduction (performed by a large group of heterotrophic facultative anaerobic bacteria) that may ultimately produce molecular nitrogen through a series of intermediate gaseous nitrogen oxide products.

Purple bacteria or purple photosynthetic bacteria are proteobacteria that are phototrophic. They are capable of producing their own food via photosynthesis. They are pigmented with bacteriochlorophyll a or b, together with various carotenoids, which gives them colours ranging among purple, red, brown and orange. It does not evolve oxygen.

Opium is the dried latex that is obtained from Papaver somniferum. Opium latex contains approximately twelve percent of morphine.

Glycolysis is the breakdown of glucose by enzymes, releasing energy and pyruvic acid.

The major structural component of the cell wall is peptidoglycan, which is a complex molecule that is composed of alternating units of N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM) and is cross-linked by short peptides.

UV rays can damage the eyes as more than 99% of UV radiation is absorbed by the front of the eyes. Corneal damage, cataract and macular degeneration are all possible chronic effects from UV exposure and can ultimately lead to blindness. Melanoma, a type of skin cancer, can also develop within the eye.

It is the second stage of cell division, between prophase and anaphase, during which the chromosomes become attached to the spindle fibres on the equatorial plate.