Test: Animal Tissues - 2 - UPSC MCQ

Red pigment of vertebrate blood is haemoglobin. Haemoglobin is a conjugated protein. It consists of a basic protein globin joined to a nonprotein group heme, hence the name haemoglobin. Heme is an iron-porphyrin ring. A mammalian haemoglobin molecule is a complex of 4 heme molecules joined with 4 globin molecules.

There are two types of ossification centers – prim... moreary and secondary. A primary ossification center is the first area of a bone to start ossifying. It usually appears during prenatal development in the central part of each developing bone. In long bones, the secondary centres appear in the epiphyses.

The kinesin, myosin and dynein proteins of skeletal muscle involve ATPase activity. This cause the contraction of skeletal muscles, propelling action of cillia and flagella and the intracellular transport of organelles.

Immunoglobulin A (IgA), as the principal antibody class in the secretions that bathe these mucosal surfaces, acts as an important first line of defence. IgA, also an important serum immunoglobulin, mediates a variety of protective functions through interaction with specific receptors and immune mediators. The importance of such protection is underlined by the fact that certain pathogens have evolved mechanisms to compromise IgA-mediated defence, providing an opportunity for more effective invasion. IgA function may also be perturbed in certain disease states, some of which are characterized by deposition of IgA in specific tissues. This review details current understanding of the roles played by IgA in both health and disease.

The medial rectus is an extraocular muscle that attaches to the side of the eye near the nose. It moves the eye inward toward the nose. The lateral rectus is an extraocular muscle that attaches to the side of the eye near the temple. It moves the eye outward.

 

Axon is generally one and it is covered by myelin sheet.

Tissues can be categorized based on the cell types that are present. If a tissue contains only one cell type it is called a simple tissue. If a tissue contains more than one cell type it is a complex tissue.
(i) Simple Tissues (made up of one cell type).
(ii) Complex Tissue (made up of more than one cell type)

B is the correct answer because lymphocytes are special type of WBC which helps us to kill the germ inside our body.

The respiratory or gas - exchange surface consists of millions of small sacs, or alveoli, lined by a simple squamous  epithelium. This epithelium is exceedingly thin to facilitate diffusion  of oxygen and CO2. The alveolar walls also contain cuboidal surfactant - secreting cells.

The main characteristic of epithelial tissues is cells can be subjected to rapid division. Epithelial tissue is abundant all over the body. They form the covering of all surfaces of the body, line cavities of the body, and hollow organs and are the main tissue in glands.

The pH of the  extracellular fluid, including the blood plasma, is normally tightly regulated between  7.32 and 7.42 , by the chemical buffers, the respiratory system, and the renal system. 
So, the correct answer is Alkaline.

B is the correct option.Hyaline cartilage is a type of connective tissue found in areas such as the nose, ears, and trachea of the human body. The word hyaline means “glass-like”, and hyaline cartilage is a glossy, greyish-white tissue with a uniform appearance.

The lacunae are situated between the lamellae, and consist of a number of oblong spaces. In an ordinary microscopic section, viewed by transmitted light, they appear as fusiform opaque spots. Each lacuna is occupied during life by a branched cell, termed an osteocyte, bone-cell or bone-corpuscle. Lacunae are connected to one another by small canals called canaliculi. A lacuna never contains more than one osteocyte. Sinuses are an example of lacuna.

The organic portion or protein fibers found in connective tissues are either collagen, elastic, or reticular fibers. Collagen fibers provide strength to the tissue, preventing it from being torn or separated from the surrounding tissues.

Muscles are composed of bundles of single large cells (called muscle fibers) that form by cell fusion and contain multiple nuclei. Each muscle fiber contains many myofibrils, which are bundles of actin and myosin filaments organized These bands correspond to the presence or absence of myosin filaments.

Lysosomes are referred to as the "suicide bag" of the cell because its enzymes digest the cell itself

B is the correct option.Osteocytes derive from osteoblasts, or bone-forming cells, and are essentially osteoblasts surrounded by the products they secreted. Cytoplasmic processes of the osteocyte extend away from the cell toward other osteocytes in small channels called canaliculi.

The bone marrow is composed of:
A: Muscle fibres and adipose tissue
- This is incorrect. Muscle fibres and adipose tissue are not components of bone marrow.
B: Areolar tissue and adipose tissue
- This is incorrect. Areolar tissue and adipose tissue are not components of bone marrow.
C: Adipose tissue and calcified cartilage
- This is incorrect. Calcified cartilage is not a component of bone marrow.
D: Adipose tissue, areolar tissue and blood vessels
- This is correct. Bone marrow is composed of:
- Adipose tissue: This is the main component of bone marrow and provides cushioning and support to the bone.
- Areolar tissue: This loose connective tissue helps in providing structural support to the bone marrow.
- Blood vessels: Bone marrow contains a network of blood vessels that supply oxygen and nutrients to the cells within the marrow.
In conclusion, the correct answer is D: Adipose tissue, areolar tissue, and blood vessels are the components of bone marrow.

The longitudinal canals of the bone are called Haversian canals.

Explanation:
The Haversian canals, also known as osteons, are found in compact bone tissue. These canals run parallel to the long axis of the bone and contain blood vessels, nerves, and connective tissue. They are responsible for providing nutrients and oxygen to the bone cells and removing waste products.
The structure of the Haversian canal system includes the following components:
1. Lamellae: These are concentric rings of bone tissue that surround the Haversian canal. They are composed of collagen fibers and mineralized matrix, giving the bone its strength and rigidity.
2. Lacunae: These are small spaces located between the lamellae. They house osteocytes, which are mature bone cells responsible for maintaining the bone tissue.
3. Canaliculi: These are tiny channels that radiate from the lacunae and connect neighboring osteocytes. They allow for communication and exchange of nutrients and waste products between the cells.
4. Volkmann's canals: These are transverse canals that connect the Haversian canals. They provide additional pathways for blood vessels and nerves to travel between adjacent osteons.
In conclusion, the longitudinal canals of the bone are called Haversian canals, which play a crucial role in the nourishment and health of the bone tissue.

The correct answer is B as Volkmann's canals are small channels in bone that transmit blood vessels from the periosteum into the bone and that lie perpendicular to and communicate with the Haversian canals. It is named after Volkmann Alfred Wilhelm. It is only found in bones of mammals. Hence, option C is correct.