(i) The cancerous cells migrate to distant parts of the body and affect new tissues.

(ii) This process is called metastasis.

Genetic factors, Physical inactivity, Eating habits (over eating), Endocrine factors.

Bronchitis, Pulmonary tuberculosis, Emphysema, Oral cancer, Lung Cancer, hypoxia, Gastric and duodenal ulcers.

The DNA fragment inserted is called transgene. Plants or animals expressing a modified endogenous gene or a foreign gene are known as transgenic organisms.

Embryonic stem cells and Somatic stem cells.

Diet Management:

(i) Reduction in the intake of calories, low saturated fat and cholesterol rich food, low carbohydrates and common salt are some of the dietary modifications.

(ii) Dietrich in polyunsaturated fatty acids (PUFA) is essential.

(iii) Increase in the intake of fibre diet, fruits and vegetables, protein, minerals and vitamins are required.

Physical activity: Regular exercise, walking and yoga are essential for body weight maintenance

Addictive substance avoidance : Alcohol consumption and smoking are to be avoided.

(i) DNA fingerprinting technique is widely used in forensic applications like crime investigation such as identifying the culprit. It is also used for paternity testing in case of disputes.

(ii) It also helps in the study of genetic diversity of population, evolution and speciation.

a. Somatic gene therapy and germ line gene therapy :

b. Undifferentiated cells and differentiated cells :

(i) Education and counselling: Education and proper counselling will help the alcoholics to overcome their problems and stress, to accept failures in their life.

(ii) Physical activity: Individuals undergoing rehabilitation should be channelized into healthy activities like reading, music, sports, yoga and meditation.

(iii) Seeking help from parents and peer groups: When a problematic situation occurs, the affected individuals should seek help and guidance from parents and peers. This would help them to share their feeling of anxiety, wrong doing and get rid of the habit.

(iv) Medical assistance: Individual should seek help from psychologists and psychiatrists to get relieved from this condition and to lead a relaxed and peaceful life.

(v) Alcohol de-addiction and rehabilitation programmes are helpful to the individual so that they could get rid of the problem completely and can lead a normal and healthy life.

Gene Cloning:

(i) The carbon copy of an individual is often called a clone. However, more appropriately, a clone means to make a genetically exact copy of an organism.

(ii) Fragment is inserted into a bacterial cell where DNA will be multiplied (copied) as the cell divides.

Basic steps involved in gene cloning:

i. Isolation of desired DNA fragment by using restriction enzymes.

ii. Insertion of the DNA fragment into a suitable vector (Plasmid) to make rDNA.

iii. Transfer of rDNA into bacterial host cell (Transformation).

iv. Selection and multiplication of recombinant host cell to get a clone.

v. Expression of cloned gene in host cell. Using this strategy several enzymes, hormones and vaccines can be produced.