STD 11 - 17. Locomotion and movement — NEET STD 11 Science — Question

Where would you find mast cells

A chemical that prevents blood clotting is most useful in the treatment of

Cretaceous period of the Mesozoic era is characterised by which of the following?

Read the following.
(i) The humoral-mediated immune response is responsible for graft rejection.
(ii) When immunity develops in host due to exposure to antigen, it is called active immunity and when immunity develops due to administration of ready-made antibodies, it is called passive immunity.
(iii) The yellowish fluid colostrum secreted by mother during initial days of lactation has abundant antibodies IgG to protect infant.
(iv) The principle of vaccination is based on the property of memory of immune system.
(v) Using recombinant DNA technology, hepatitis A vaccine is produced from yeast.
(vi) The exaggerated response of immune system to certain antigens called allergens in the environment is known as allergy. The antibody produced in such response are IgE type.
(vii) Allergy is due to release of chemicals like histamine and serotonin from the mast cells.
(viii) The use of drug like anti-histamine, adrenalin and steroids quickly reduces symptoms of allergy.
(ix) Memory based innate immunity is evolved in vertebrate.
(x) Rheumatoid arthritis is an example of auto immune response.
(xi) The primary lymphoid organs in our body are bone marrow and thymus.
(xii) After maturation, the lymphocyte migrate to secondary lymphoid organs where interaction of lymphocyte with antigen occur.
(xiii) Spleen organ has a large reservoir of leukocytes.
choose the option with all incorrect statements :-

Mark the given statements True (T) or False (F).
(i) Squamous epithelium is found in wall of blood vessels and air sacs of lungs.
(ii) Cuboidal epithelium is found in ducts of glands and Henle's loop of nephrons.
(iii) Columnar epithelium lines the inner surface of stomach and intestine.
(iv) The columnar or cuboidal cells bearing cilia on their surface are called ciliated epithelium and are present in inner surface of solid organs like bronchioles and fallopian tubes.
(V) The goblet cells of alimentary canal has unicellular type of glandular epithelium whereas salivary gland has multicellular type.
(vi) Compound epithelium covers the dry surface of the skin, moist surface of buccal cavity, pharynx, innerlining of duct of salivary gland and of pancreatic duct.
(vii) Tight junctions help to stop substances from leaking across a tissue whereas gap junction facilitate cells to communicate with each other by connecting the cytoplasms of adjoining cells.
(viii) Adhering junctions performs cementing to keep neighbouring cells together.
(ix) In all connective tissue the cells secrete fibres of structural proteins called collagen or elastin.
(x) Tendon attach skeletal muscles to bones and ligament attach one bone to another and both are example of loose regular type of connective tissue,
(xi) The cells of cartilage called chondrocytes are enclosed in large cavities within matrix secreted by them.
(xii) The cells of bone called osteocytes are present in the spaces called lacunae.
(xiii) The bone-marrow in all bone is the site of production of blood cells.
(xiv) The fibres of muscle tissue are composed of numerous fine fibrils, called myofibrils,
(xv) The smooth muscle fibres taper at both ends (fusiform) and show striation.
Choose the correct option given below :-

Statement I: Fishes have a 2-chambered heart with an atrium and a ventricle.
Statement II: Amphibians & reptiles have a 3- chambered heart with two atria & a single ventricle without any exception.

Assertion: Failure of secretion of hormone vasopressin causes diabetes mellitus in the patient.
Reason: Vasopressin increases the volume of urine by increasing the reabsorption of water from the urine.

Which of the following organism is not a source of restriction endonuclease?