The main reason why antibiotics could not solve all the problems of bacteria mediated diseases is
insensitivity of the individual following prolonged exposure to antibiotics
inactivation of antibiotics by bacterial enzymes
decreased efficiency of the immune system
the development of mutant strains resistant to antibiotics.
D.
the development of mutant strains resistant to antibiotics.
A major problem in the treatment of bacterial mediated diseases is that many bacteria have been found to show resistance to antibiotics. The emergence of antibiotic-resistant bacteria is closely linked to the extent that antibiotics are used in humans and items of human diet. Resistant strains may appear rapidly or slowly, according to the amount or type of antibiotic used. Bacteria occur in such large numbers that there is a high chance of a mutant individual eventually appearing in the population. As soon as it does, use of the antibiotic to which it is resistant will give it a selective advantage over non-resistant types and it will multiply and eventually become the dominant type.
Antibiotics may also be destroyed by enzymes inside the cells being targetted. A well-known and important example is the group of enzymes known as penicillinases which hydrolyses and destroys penicillins and cephalosporins.
Acrosome reaction in sperm is triggered by
capacitation
release of lysin
influx of Ca++
release of fertilizin
One of the major difficulties in the biological control of insect pest is that
the predator develops a preference to other diets and may itself become a pest
the predator does not always survive when transferred to a new environment
the method is less effective as compared with the use of insecticides
the practical difficulty of introducing the predator to specific areas.
Smoking addiction is harmful because it produces polycyclic aromatic hydrocarbons, which cause
reduction in oxygen transport
increase in blood pressure
cancer
retardation of growth of foetus.
Which one of the following pairs is not correctly matched
Streptomyces - Antibiotic
Serratia - Drug addiction
Spirulina - Single cell protein
Rhizobium - Biofertilizer
The bacteria which attack dead animals are
first link of the food chain and are known as primary producers
second link of the food chain and are herbivorous
third link of the food chain and are tertiary consumers
the end of food chain and are decomposers.
The binding of antibodies to the antigens to produce a large insoluble complex is known as
antibody-antigen complex
agglutination
immunisation
suppressor cell reaction.
What is a keystone species
A species which makes up only a small proportion of the total biomass of a community, yet has a huge impact on the community's organization and survival.
A common species that has plenty of biomass, yet has a fairly low impact on the community's organization.
A rare species that has minimal impact on the biomass and on other species in the community.
A dominant a large proportion of the biomass and which affects many other species.
Which of the following sets includes all bacterial disease
Cholera, typhoid, mumps
Tetanus, tuberculosis, measles
Malaria, mumps, poliomyelitis
Diphtheria, leprosy, plague
Which of the following statements is incorrect
Lichen, an association of fungus and algae is an example of mutualism.
Those epiphytes which use other plants for support only and not for water or food supply and are examples of commensalism.
Sea-anemone on hermit-crab is an example of protocooperation.
Mutualism, protoocoperation, commensalism cannot be included under symbiosis.
