BT403 Final Term Solved Papers

Collective short and long questions

Anthesis

Anthesis is the first opening of a flower during process of flowering. It is the period when a flower becomes sexually functional. It means anthesis facilitates the pollination by opening of flower.

Who created the first recombinent DNA

Paul Berg, a biochemist at Stanford who was among the first to produce a recombinant DNA molecule in 1972,

Mechanisms of resistance of plant

Plant immune systems rely on their ability to recognize enemy molecules, carry out signal transduction, and respond defensively through pathways involving many genes and their products. Pathogens actively attempt to evade and interfere with response pathways, selecting for a decentralized, multicomponent immune system.

Factors cause abiotic stress in plants

High temperature or low temperature, salinity, drought or flooding, nutrient deficiency or metal toxicity are a few of the major abiotic stress conditions a plant faces daily during its life cycle.

Importance of protoplast

Protoplast culture is an important tool in the production of new plant varieties. By fusing protoplasts from different plant species, scientists can create hybrid plants with desirable characteristics, such as resistance to disease, increased yield, and improved quality. Reduction of chlorophyll in case of plant disease

Conditions of embryo culture

Culture conditions consisting of 3. 5% oxygen have been shown to lead to higher rates of fertilization and cleavage (54). One major reason why a low oxygen tension is associated with improved embryo viability is possibly the effect it exerts on increasing expression of antioxidant enzymes and glucose transporters.

How positive and negative transgene results of PCR assessed

PCR-based transgene detection is a simple and highly sensitive process. Subsequent PCR tests are assessed by agarose gel electrophoresis, and results are visualized by the presence or absence of the appropriately sized DNA fragment. If PCR shows a positive result, the transgene may be present. Transgene presence is confirmed by There are several A-biotic factors that lead to a series of morphological, physiological, biochemical, and molecular changes that adversely affect plant growth and productivity.

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incorporating it into the genome by DNA sequencing. In contrast, a negative PCR result implies that the transgeneisnotpresent

How many common Types of GMOs. FOODS • Crops are modified to develop resistance to herbicides and increase their nutrient content, for example corn and soybeans . • Fruits are modified to make them ripen later. • This help them available fresh in marketplace during a longer time or for fruits that ripen after being picked, make it easier to transport them. MEDICINES • These can be produced cheaper and easier some are: insulin, thyroid hormones and the Hepatitis B vaccine • GM Bacteria‟s have been particularly important in producing large amounts of pure human proteins for use in medicine like clotting factors for hemophilia and human growth hormones to treat

Function of pr proteins

Pathogenesis-related (PR) proteins are proteins produced in plants in the event of a pathogen attack. They are induced as part of systemic acquired resistance. Infections activate genes that produce PR proteins. Some of these proteins are antimicrobial, attacking molecules in the cell wall of a bacterium or fungus.

• SA-mediated signal transduction cascades regulate the transcriptional activation of many PR genes
• Ethylene and SA have been shown to act synergistically, further enhancing the expression of PR genes

Adventages of herbicides

Pesticides help in an abundant harvest It helps keep food affordable: Pesticides help to prevent insects and waterborne transmission diseases: Pesticides help farmers to grow more crops in the same or less land Pesticides helped in making it easy to remove weeds or prevent pests without hardship: It helped globally to increase the economical growth of a country:

Application of embryo culture

Sterile seeds can be produced using embryo culturing techniques. The process of embryo culture is a savior when you need to produce viable embryos from interspecific and intergeneric crosses that generally result in the production of non-viable seeds

Heat stress effects on plant

Dehydration. • Yellowing of plants and leaves; chlorophyll deteriorates. • Withered leaves • Sunburn; reddish-purple tint or freckles on leaves and pseudo bulbs, leaf tip

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and root may turn brown. • Alteration of gene expression is the major cause of heat stress. • Leathery leaves; damage on cellular level. • In response to high temperature all organisms, including plants, synthesize a set of proteins called as heat shock proteins (HSPs) The induction of HSPs at permissive temperatures have been associated with the acquisition of thermotolerance to withstand the stress

Threatens of GMOs to crop diversity

• There is opposition to introducing GM genes on genetic diversity because these genes can spread to other organic farm crops and threaten crop diversity in agriculture. • And if crop diversity decreases, it will have a direct impact on our entire ecosystem and would affect the population dynamics of other organisms. • The chance that a single genetically modified crop strain could pollinate an already existing non-GM crop is unlikely and unpredictable, and there are many conditions that must be met for cross pollination to occur.

What is BT cotton

Bt cotton is a genetically modified pest resistant plant cotton variety that produces an insecticide to combat bollworm.. Strains of the bacterium Bacillus thuringiensis produce over 200 different Bt toxins, each harmful to different insects. Most notably, Bt toxins are insecticidal to the larvae of moths and butterflies, beetles, cotton bollworms and flies but are harmless to other forms of life.

What is post mitotic anthers ( Below answer is for anther culture, there is no proper answer for give Question)

AIM: To isolate and inoculate anthers for haploid production. Principle: Haploids refer to those plants which possess a gametophytic number of chromosomes in their sporophytes. Haploids may be grouped into two broad categories: Ø (a) monoploids which possess half the number of chromosomes from a diploid species. Ø (b) Polyhaploids which possess half the number of chromosomes from a polyploidy species. Haploid production through anther culture has been referred to as androgenesis while gynogenesis is the production of haploid plants from ovary or ovule culture where the female gameteorgametophyteistriggeredtosporophytic

What are botanical pesticides

These are naturally occurring plant material that may be crude preparation of the plant parts ground to produce a dust or powder that can be used in full strength or dilute form in a carrier such as clay, talc or diatomaceous earth. •“Azadirachtin” effects the reproductive and digestive procees of pest. Several plant based insecticides as nicotinoids, natural pyrethrins, rotenoids, neem products etc are used.