Question
Choose the correctly matched pair. [CBSE AIPMT 2014]
(a) Tendon-Specialised connective tissue
(b) Adipose tissue-Dense connective tissue
(c) Areolar tissue-Loose connective tissue
(d) Cartilage-Loose connective tissue
Answer/Explanation
Ans. (c)
Areolar tissue is the body’s loose connective tissue, and provide flexibility and cushioning. Adipose tissue is also loose connective tissue while, the tendon is a dense connective tissue, which connect the muscles with the bone. Cartilage is composed of specialised connective tissue called chondrocytes that produce a large amount of extracellular matrix composed of collagen fibre.
Question
The kind of tissue that forms the supportive structure in our pinna (external ears) is also found in [CBSE AIPMT 2009]
(a) vertebrae
(b) nails
(c) ear ossicles
(d) tip of the nose
Answer/Explanation
Ans. (d)
Yellow fibrous cartilage tissue is found in pinna (external ear). It is also found at the tip of the nose.
Question
Which one of the following contains the largest quantity of extracellular material? [CBSE AIPMT 2003]
(a) Myelinated nerve fibres
(b) Striated muscle
(c) Areolar tissue
(d) Stratified epithelium
Answer/Explanation
Ans. (c)
Loose connective tissue, also called areolar connective tissue, is the ‘packing material’ of the body that anchors blood vessels, nerves and body organs. It contains fibroblasts that synthesise the fibres and ground substance of connective tissue and wandering macrophages that phagocytise pathogens or damaged cells. The different fibre types include strong collagen fibres and thin elastic fibres formed of the protein elastin. Adipose (fat) tissue is considered a type of loose connective tissue.
Question
Compared to blood our lymph has [CBSE AIPMT 2009, 1989]
(a) no plasma
(b) plasma without proteins
(c) more WBCs and no RBCs
(d) more RBCs and less WBCs
Answer/Explanation
Ans. (c)
Lymph can be defined as blood minus RBCs, also it contains more WBCs. Lymph is a clear, colourless fluid, similar to plasma but with less protein. It is a mobile connective tissue like, blood and is formed by the filtration of blood. Microscopic examination of lymph depicts that it contains a large number of leucocytes (mostly lymphocytes), ranging from 500-75,000 per cubic mm. But platelates are not present in lymph.
Question
The most active phagocytic white blood cells are [CBSE AIPMT 2008]
(a) neutrophils and eosinophils
(b) lymphocytes and macrophages
(c) eosinophils and lymphocytes
(d) neutrophils and monocytes
Answer/Explanation
Ans. (d)
Neutrophils and monocytes are phagocytic white blood cells. Monocytes are largest of all leucocytes and generally change into macrophages after entering tissue spaces. Neutrophils are most numerous of all leucocytes, and have many lobed nucleus. Eosinophils are granular white blood cells. Their number increases in people with allergic conditions such as asthma or hay fever. They are non-phagocytic and seem to play part in immune system. Lymphocytes are non-motile and non-phagocytic. These are found as B and T-lymphocytes. B-lymphocytes secrete antibodies to destroy microbes. T-lymphocytes either directly attack the antigens or stimulate B-lymphocytes to produce antibodies.
Question
Which type of white blood cells are concerned with the release of histamine and the natural anticoagulant heparin? [CBSE AIPMT 2008]
(a) Neutrophils
(b) Basophils
(c) Eosinophils
(d) Monocytes
Answer/Explanation
Ans. (b)
The basophils are probably like mast cells of connective tissue. They release heparin, (a natural anticoagulant), histamine and serotonin. Their nucleus is usually three lobed and their granules take basic stain strongly.
Monocytes are largest of all types of leucocytes. Their nucleus is bean-shaped. They are motile and phagocytic in nature and engulf bacteria and cellular debris. Generally, they change into macrophages after entering tissue spaces.
Eosinophils have two-lobed nucleus. They are non-phagocytic and help in dissolving blood clot. Their number increases in people with allergic conditions such as asthma or hay fever. Neutrophils are most numerous of all leucocytes. They eat harmful germs and are therefore, phagocytic in nature. Their nucleus is many lobed and stain weakly with both acid and basic stains.
Question
Which one of the following mammalian cells is not capable of metabolising glucose to carbon-dioxide aerobically? [CBSE AIPMT 2007]
(a) White blood cells
(b) Unstriated muscle cells
(c) Liver cells
(d) Red blood cells
Answer/Explanation
Ans. (d)
Cell organelles and nucleus are absent in mature red blood cells. Therefore, aerobic respiration do not take place red blood cells.
Question
A drop of each of the following, is placed separately on four slides. Which of them will not coagulate? [CBSE AIPMT 2007]
(a) Blood plasma
(b) Blood serum
(c) Sample from the thoracic duct of lymphatic system
(d) Whole blood from pulmonary vein
Answer/Explanation
Ans. (b)
Serum will not coagulate if placed separately on a slides. This is because in blood, the serum is the component that does not contain blood cell (WBCs or RBCs) nor any clotting factor. It is the blood plasma without the fibrinogens.
Question
Areolar connective tissue joins [CBSE AIPMT 2006]
(a) integument with muscles
(b) bones with muscles
(c) bones with bones
(d) fat body with muscles
Answer/Explanation
Ans. (a)
Loose or areolar connective tissue is the most generalised connective tissue, which is spread extensively throughout the body under the skin and epithelium, around and in between the muscles, nerves and blood vessels, between lobes and lobules of compound glands, in the sub-mucosa of respiratory and gastrointestinal tracts.
It functions mainly for binding the parts together but also helps in sliding movement of epithelia, muscles and other parts and also forms the internal histological framework or stroma of many solid organs.
Question
Mast cells of connective tissue contain [CBSE AIPMT 2004]
(a) vasopressin and relaxin
(b) heparin and histamine
(c) heparin and calcitonin
(d) serotonin and melanin
Answer/Explanation
Ans. (b)
Mast cells are granulated wandering leucocyte cells. Their granules contain histamine which is vasodilator and heparin (anticoagulant). These take part in body defence and allergic reaction.
Question
Which cartilage is present at the end of long bones? [CBSE AIPMT 2002]
(a) Calcified cartilage
(b) Hyaline cartilage
(c) Elastic cartilage
(d) Fibrous cartilage
Answer/Explanation
Ans. (b)
Hyaline cartilage is present at the end of long articular bones. It provides a smooth articular surface to permit movement at joints. Elastic cartilage is found where support with flexibility is needed such as in external ears. Fibrous cartilage is a very tough substance and is used in places of the body where shock absorbers are needed, e.g. discs between the vertebrae and in the knee joint.
Question
During an injury nasal septum gets damaged and for its recovery which cartilage is preferred? [CBSE AIPMT 2001]
(a) Hyaline cartilage
(b) Elastic cartilage
(c) Calcified cartilage
(d) Fibrous cartilage
Answer/Explanation
Ans. (a)
Hyaline cartilage forms nasal septum, larynx, trachea and hyoid apparatus.
Question
The polysaccharide present in the matrix of cartilage is known as [CBSE AIPMT 2000]
(a) cartilagin
(b) ossein
(c) chondriotin
(d) casein
Answer/Explanation
Ans. (c)
The chief component of ground substance of cartilage is chondromucoprotein which is formed of chondriotin sulphate, keratin sulphate and hyaluronic acid.
Question
Formation of cartilage bones involves [CBSE AIPMT 1993]
(a) deposition of bony matter by osteoblasts and resorption by chondroclasts
(b) deposition of bony matter by osteoclasts and resorption by chondroblasts
(c) only deposition of bony matter by osteolasts only
(d) deposition of bony matter by osteoblasts only
Answer/Explanation
Ans. (d)
Osteoblasts are bone forming cells while osteoclasts are bone-destroying cells. Ossification or osteogenesis is the process of bone formation.
Chondroblasts are cartilage forming cells.
Question
Component of blood responsible for producing antibodies is [CBSE AIPMT 1992]
(a) thrombocytes
(b) monocytes
(c) erythrocytes
(d) lymphocytes
Answer/Explanation
Ans. (d)
Lymphocytes (20-25\%) are the second most abundant leucocytes. These protect us from pathogens and are involved in the production of antibodies. These lymphocytes are of two types, which are known as B-lymphocytes and $\mathrm{T}$-lymphocytes.
Question
Histamine secreting cells are found in [CBSE AIPMT 1989]
(a) connective tissue
(b) lungs
(c) muscular tissue
(d) nervous tissue
Answer/Explanation
Ans. (a)
Histamine is a vasodilator, involved in allergic and inflammatory reactions. It is secreted by mast cells, these are modified basophils of blood that occur in areolar tissue i.e. the loose connective tissue.
Question
Haversian canal occurs in [CBSE AIPMT 1989]
(a) humerus
(b) pubis
(c) scapula
(d) clavicle
Answer/Explanation
Ans. (a)
Haversian canal, named after ‘Clopton Havers’ are fine channels parallel to the long axis of mammalian bone containing blood vessels, nerve fibres, connective tissue and occasionally Iymphatic vessels. Haversian system is found in long bones of mammals (humerus among given options) and absent in spongy bones of mammals.
Question
Mineral found in red pigment of vertebrate blood is [CBSE AIPMT 1989]
(a) magnesium
(b) iron
(c) calcium
(d) copper
Answer/Explanation
Ans. (b)
Haemoglobin constitutes about $33 \%$ of red blood cells. It is a conjugated protein, composed of a protein called globin and an $\mathrm{Fe}^{2+}$ porphyrin complex called heme. The mineral present in the red pigment (haemoglobin) of vertebrate blood is iron.