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A fertilized ovule undergoes the following changes in the ovary in an angiosperm plant :

Unfertilized ovule  → Fertilized ovule  → Seed

Funiculus  → Present

Hilum  →  Present

Integument  → Seed coat

Outer integument  → Testa

Inner integument  → Tegmen

Chalaza       →  Present

Micropyle   → Present

Nucellus   →  Absent or present as perisperm

Embryo Sac :

Antipodal cells → Degenerate

Synergid cell  → Degenerate

Secondary nucleus  → Endosperm

Egg      →  Embryo

When the unfertilized ovule undergoes double fertilization, it makes fertilized ovule and then seeds.  In this process funiculus and hilum are present. Outer integument makes testa and inner integument is tegmen. Chalaza and micropyle are present but nucellus is absent, partly persists as perisperm. In embryo sac antipodals and synergids degenerate. The central cell makes endosperm, cl'ranges into embryo.

Spirulina or Methylophilus methylotropus can be cultured as food source. Spirulina a rich source of protein produces large quantity of food rich in protein, fat, carbohydrates and vitamins. It has been estimated that about 250 gm of methylophilus methylotropus produces about 25 tonnes of protein per day.

a.

i. Failed to keep pace with demand.

ii. Failed to provide fast and efficient system of crop improvement.

b.

i. Large number of plants can be developed in a short duration.

ii. Production of genetically identical plants or somaclones.

iii. Healthy plants can be recovered from diseased plants.

c. Tomato, banana, apple.

The answer to address both these problems is biofortification. This looks at improving food quality with respect to protein, oil, vitamin, micro-nutrient and mineral content. The oils need to be rich in omega-3 fatty acids which are good for heart. Similarly, proteins should have more of lysine and tryptophan (essential amino acids). Many varieties of maize, carrots and spinach have been released which fulfill the above criteria.

The advantages of tissue culture methods are:

By application of these methods it is possible to achieve propagation of a large number ofplants in very short durations. This method of producing thousands of plants through tissue culture is called micro-propagation. Each of these plants will be genetically identical to the original plant from which they were grown, i.e., they are somaclones. Many important food plants like tonjato, banana, apple, etc., have been produced on commercial scale using this method. Try to visit a tissue culture laboratory with your teacher to better understand and . appreciate the process. Another important application of the method is the recovery of healthy plants from diseased plants. Although the plant is infected with a virus, the meristem (apical and axillary) is free of virus. Hence, one can remove the meristem and grow it in vitro to obtain virus-free plants. Scientists have succeeded in culturing meristems of banana, sugarcane, potato, etc.

Angiosperms produce non-motile gametes. They reach the female gamete with the help of air or water.

Parthenogenesis

Spirulina or Methylophilus methylotrophus can be cultured as a food source. Spirulina produces large quantities of food rich in protein, minerals, fats, carbohydrates and vitamins.

250 gm of Methylophilus methylotrophus produces 25 tonnes of protein per day. (Any one)

(a) Micropropagation

(b) Somaclones

The phenomenon of development of female gamete directly into an individual without fertilisation is called parthenogenesis, e.g., rotifers, honeybees, lizards and birds.

Somatic hybridisation –

The isolated cells from to-mato and potato are converted into naked protoplasts by digesting the cell walls. Isolated protoplasts of the two plants are fused to get hybrid protoplasts which is further grown to form a new plant. Somatic hybrid of tomato and potato is called Pomato.

The management of animals for milk and their products for human consumption.

Spirulina can be grown easily on materials like waste water from potato processing plants, straw, molasses, animal manure, sewage. This way it reduces environmental pollution and hence is environmentally beneficial. It serves as food rich in protein, carbohydrate, fats, vitamins and minerals. Thus, it is nutritionally beneficial too.

Spirulina is a source of food rich in protein, minerals, fats, carbohydrates and vitamins. It can grow on waste water from potato processing plants, straw, molasses, animal manure and even sewage, so it also reduces water pollution.

Biofortification refers to breeding of crops to produce varieties with higher levels of nutrients like vitamins, minerals, high protein content or healthier fats.

Breeding steps

a) screening germ plasm

b) hybridization of selected parents

c) selection and evaluation of hybrid

d) testing and release of new varieties

Microbes are being grown on an industrial scale as source of good protein. Microbes like Spirulina can be grown easily on materials like waste water from potato processing plants (containing starch), straw, molasses, animal manure and even sewage, to produce large quantities and can serve as food rich in protein, minerals, fats carbohydrate and vitamins. Incidentally such utilisation also reduces environmental pollution and hence is environment friendly.

a. Apis indica/Apis mellifera/Apis dorsata

b. Leghorn/Rhode island red/Minorcha.

Spirulina can serve as food rich in proteins, minerals, vitamins, fats and carbohydrates.

The wheat variety Himgiri developed, which is resistant to leaf and stripe rust.

South Indian sugarcane has thicker stem and higher sugar content.

Study of basic biological process—how genes are regulated, how they affect the normal functions of the body and its development. Transgenic cow, Rosie is an example for the second category.

Mature functional insulin is obtained by processing of pro-hormone which contains extra peptide called C-peptide. This C-peptide is removed during maturation of pro-insulin to insulin.

The stalk of the leaf is called petiole Functions:

• In helps to hold the leaf blade to the light
• It also helps the blade to flutter in wind.

 Carpels are free in apocarpous ovary, while they are fused in syncarpous ovary.

(i) Sessible 

(ii) Lamina 

(iii) Phyllotaxy 

(iv) Stipules 

(b)

1. Epipetalous stamens: When the stamens are united to petals they are described as epipetalous stamen. E.g. Datura

2. Epiphyllous stamens: When the stamens are united to tepals they are described as epiphyllous stamens. E.g. Lily

3. Syngenesious stamens: When anthers are united and filaments are free, such stamens are called as syngenesious stamens. E.g. Sunflower

4. Synandrous stamens: When both anthers and filaments are fused, such stamens are called as synandrous stamens. E.g. Cucurbita

a. Aestivation: The mode of arrangement of sepals or petals; with respect to the other members of the same whorl is called aestivation. 

b. Placentation: The arrangement of ovules in the ovary is called placentation. 

c. Actinomorphic: When a flower shows radial symmetry, it is called an actinomorphic flower, e.g. mustard, datura, chilli, etc. 

d. Zygomorphic: When a flower shows bilateral symmetry, it is called a zygomorphic flower, e.g. pea, gulmohar, bean, Cassia, etc. 

e. Superior Ovary or Hypogynous Flower: When the ovary occupies the highest position and other floral parts are below it, the flower is called hypogynous. In this case, the ovary is said to be superior, e.g. mustard, China rose, brinjal, etc.

 f. Perigynous Flower: When the ovary and other parts of the flower are situated at the same level, the flower is called perigynous. In this case, the ovary is said to be half-inferior, e.g. plum, rose, peach, etc. 

g. Epipetalous Stamens: When stamens are attached to the petals, this arrangement is called epipetalous, e.g. brinjal.

1. Phyllotaxy shown by leaves of Mango is alternate phyllotaxy. In this type, single leaf from each node. 

2. Phyllotaxy shown by leaves of Nerium is whorled phyllotaxy. In this type, many leaves arise from each node and form a whorl. 

3. Phyllotaxy shown by leaves of Jamun is opposite superposed phyllotaxy. In this type, a pair of opposite leaves are arranged one above the other in the same plane.

Types of phyllotaxy : 

(i) Alternate : Single leaf at a node. e.g., China rose, Mustard

(ii)  Opposite : Two leaves at a node. e.g., Calotropis, guava

(iii) Whorled : More than two leaves in a whorl at a node. e.g., Nerium, devil tree

Experiments with Drosophila-linkage & recombination.

Yes. One can use antibody against the enzyme (that is responsible for the metabolism of phenylalanine) to develop ELISA-based diagnostic technique. The patient in which the enzyme protein is absent would give negative result in ELISA when compared to normal individual.

Phyllotaxy: The arrangement of leaves on the stem or branch is called phyllotaxy. There are three types of phyllotaxy, which are as follows: 

a. Alternate: In this type of leaf arrangement, a single leaf arises at each node in alternate manner, e.g. China rose, mustard, sunflower, etc. 

b. Opposite: In this type of leaf arrangement, a pair of leaves arise at each node. The leaves lie opposite to each other in this case, e.g. Calotropis, guava, etc. 

c. Whorled: In this type of leaf arrangement, more than two leaves arise at a node, e.g. Alstonia.

Male Heterogamety : Male produced two type of gametes. Eg. Human, Drosophila. 

Female heterogamety : female produced two type of gametes. Eg.Birds.

TH Morgan is a Genetist who got Nobel Prize.

• He found fruit fly (Drosophila Melanogaster) to be a experimental material as it was easy to rear and multiply it. 
• Established presence of genes over the chromosomes.
• Principle of linkage and crossing over. 
• Discovered sex linkage and crossing over. 
• He observed mutations.
• Developed technique of chromosome mapping,
• Wrote book “The theory of Gene”.

Two uses of PCR technique:

i. It is used to detect HIV in suspected AIDS patients. ii. It is used to detect mutations in gene, in suspected cancer patients.

i. It is used to detect HIV in suspected AIDS patients.

ii. It is used to detect mutations in gene, in suspected cancer patients.

Mendel selected pea plant because:-

• It possesses a large number of varieties.
• Pure varieties of this plant were available.
• Plant is small and flower is large enough to hand manually. 
• Flowers are bisexual and produces fertile hybrids. 
• Each plant produces a large number of seeds. 
• Plants are self pollinated and can be cross pollinated.
• Plant is annual with growth period of few months. 
• Chances of contamination are very less.

A single stranded small DNA or RNA is tagged with radioactive molecule to be used as a probe. The probe is hybridised with DNA in cancer cells, to be followed by autoradiography. The clone with mutated gene will not appear in the autoradiography, because the probe will not have the complementary sequence with mutated gene.

(b) Retrovirus

The three molecular diagnostic techniques that help to detect pathogens from suspected patients are:

a. Recombinant DNA technology

b. Polymerase chain reaction (PCR)

c. Enzyme-linked immunosorbent assay (ELISA)

These techniques are better than the conventional methods because they help in early diagnosis of the disease even when the bacteria or virus concentration is very low.

1. Gene therapy. 

2. Lymphocytes are taken from patient’s blood it is grown invitro culture. By using retroviral vector functional ADA cDNA (from WBC of normal person) is introduced into vitro cultured lymphocytes These genetically engineered lymphocytes (corrected functional lymphocytes) are reinjected into the patients.

3. If the ADA producing genes are introduced into cells at early embryonic stage it could be a permanent cure.

Eli Lilly prepared two DNA sequences corresponding to A and B chains of human insulin and introduced them in plasmids of E. coli to produce insulin chains. Chains A and B were produced separately, extracted and combined by creating disulfide bonds to form human insulin. Insulin in human pancreas is synthesised as a pro-hormone containing the C peptide, which is removed to form mature hormone. The synthesised insulin did not contain C peptide and was directly prepared in mature form.

1. Enzyme-Linked Immuno Sorbent Assay

2. Genetic Engineering Approval Committee

3. RNA interference

PCR-By amplification of the DNA of vims or bacteria present in the patient helps to identify even the concentration of pathogen is very low in the body of the patient.

A single stranded DNA or RNA is tagged with a radio active molecule (probe) is allow to hybridized to its complementary DNA in clone of cells followed by detection using autoradiography. Thus the mutated gene can be detected as it will not hybridize with the probe.

ELISA – Enzyme linked immuno- sorbent assay is based on the principle of antigen antibody reaction. Infection by pathogen is an antigen it can be detected by the presence of antibodies synthesized against it.

a. Eli Lilly prepared two DNA sequences corresponding to the A and B chains of human insulin.

b. Sticky ends were produced in the Escherichia coli plasmid and the insulin gene by treating them both with the same restriction endonucleases.

c. These two are then joined together by the enzyme DNA ligase.

d. The bacteria are then grown in sterilised bioreactors in the appropriate growth medium.

e. The chains A and B are produced separately, extracted and purified.

f. These two chains are then combined by creating disulfide bonds to form human insulin.

1. Polymerase Chain Reaction Enzyme Linked Immuno Sorbent Assay

2. Antigen-antibody interaction.

Plasmids are extra-chromosomal, self-replicating, usually circular, doublestranded DNA molecules found naturally in many bacteria.

In 1983, Eli Lilly an American company, first prepared two DNA sequences corresponding to A and B chains of human insulin and introduced them in plasmids of E. coli to produce insulin chains. These chains A and B were produced separately, extracted and combined by creating disulfide bonds to form functional human insulin (humulin).