Filariasis is caused by
dead adult filariae
microfilariae
biting of filarial worm
presence of bacteria in filarial wall
B.
microfilariae
Filariasis also called elephantiasis is caused by Wuchereria bancrofti or filarial worm. It spreads by bite of Culex mosquito.
Which of the following conditions is related to haemophilia?
A responsible recessive gene present in the X-chromosome
A responsible dominant gene presentin the X-chromosome
A responsible dominant gene present in the Y-chromosome
A responsible dominant gene present in the autosomal chromosome
A.
A responsible recessive gene present in the X-chromosome
Haemophilia is the most serious and notorious disease which is more common in man than in woman. The person which contains the recessive gene for haemophilia lacks normal clotting substance (thromboplastin) in blood so, amino injuries cause continuous bleeding and ultimate death. It is X-linked disease.
Active immunity development is related to
natural killer cells
memory cells
helper T cells
suppressor T cells
B.
memory cells
Active immunity involves the active functioning of the person's own immune system which leads to synthesis of antibodies and or the production of immunologically active cells.
The absence of which clotting factor leads to haemophilia-A?
Factor VII
Factor VIII
Factor IX
Factor X
B.
Factor VIII
Haemophilia-A is characterized by lack of antihaemophilic globulin (factor VIII). Haemophilia is caused due to X-linked recessive gene.
The equation = B represents, which of the following?
Natality
Growth rate
Mortality
All of these
A.
Natality
Natality or birth rate is the rate of production of new individuals per unit of population per unit time through birth. Natality is expressed as and = Specific natality rate.
Down's syndrome occurs as a result of
trisomy
tetrasomy
autopolyploidy
allopolyploidy
A.
trisomy
Down's Syndrome is Trisomy of 21st chromosome. It is characterized by mental retardation, short stature with stubby fingers and heart defects.
Passive immunity can be obtained through
antigens
vaccines
antibiotics
antibodies
D.
antibodies
In passive immunity, antibodies from one individual are passed into another individual. They give immediate protection unlike active immunity which takes a few days or weeks to build up. However, it only provides protection against infection for a few weeks.
Indicate, the inheritance of which of the following is controlled by multiple alleles?
Colourblindness
Sickle cell anaemia
Blood group
Phenylketoneuria
C.
Blood group
A particular gene has been found to occur in two alternative forms or allelomorphs. The existence of more than two allelic forms of a gene is called multiple allelism and the alleles as multiple alleles, eg, blood group in human.
Only one of the following four ways through which AIDS can spread?
Infected needles and syringes
Through mosquito bites
Looking after AIDS patient
Shaking hands, coughing, sneezing, hugging
A.
Infected needles and syringes
There are three main router for transmission of HIV, ie, AIDS virus. These are through sexual intercourse, transmission through blood transfusion, blood products, contaminated equipments, and from mother to baby. Infected needles and syringes (ie, equipments) are most efficient method of HIV infection.
Identify which one of the following is an example, of incomplete ecosystem?
Grassland
Cave
River
Wetland
B.
Cave
Ecosystems are made up of biotic and abiotic components. Cave ecosystem is incomplete because it does not have all the biotic and abiotic (specially) components.