Answer:
Lymphocytes
Explanation:
White blood cells ( leukocytes) is one of the formed elements of blood that provides immunity and protection against the pathogens. Different types of leukocytes are eosinophils, basophils, monocytes, lymphocytes and neutrophils.
Lymphocytes are B cells and T cells of the immune system. B cells produce antibodies against the antigen and T cells kills the harmful cells of the body. by specific cell determinants.These cells are not capable of phagocyte the pathogen.
Thus, the correct answer is option (A).
Answer:
Hemophilia is a x-linked recessive inherited bleeding disorder. in this disease blood does not clot properly due to the decreased level of blood clotting factor VIII (8) or factor IX (9).
In x-linked recessive condition, the disease is transmitted from father (affected male) to his daughter and mother (affected female) to her son and skip of generation getting affected is also occurs.
- there will be 50% chance of her (S.R.) each son to be affected with hemophilia.
Explanation:
Hemophilia is caused due to mutation of one gene which is responsible for the making of proteins of blood coagulation factor viii or ix. the affected person bleeds continuously from any injury and that can cause serious issues.
here,
grandfather of s.r is affected (xₐy) and grandmother is normal (xx) will produce
↓
s.r's mother who is a carrier (xₐx) [as xₐy and xx will produce 100% carrier xₐx daughter]
↓
s.r's mother is a carrier (xₐx) but her father is normal (xy) will produce,
↓
s.r who has 50% chance of being carrier (xₐx) and 50% chance of being normal (xx) [as she is the only child] and she has a normal (xy) partner, they will give,
↓
- if s.r is a carrier (xₐx) then one of her son will be affected (xₐy) [as xₐx and xy =xₐy]
- if s.r is normal (xx) then her son will be normal (xy) [as xx and xy will give xy]
here,<u> 50% chance of her son to be affected with hemophilia</u> [as S.R of being affected is more considerable].
Mutations result either from errors in DNA replication or from the damaging effects of mutagens, such as chemicals and radiation, which react with DNA and change the structures of individual nucleotides. All cells possess DNA-repair enzymes that attempt to minimize the number of mutations that occur
