Structural Organisation in Animals Test 23

Haversian canals can be defined as a series of tubes around narrow channels formed by lamellae. This region of bone is called as cortical bone. Osteons are arranged in parallel to the long axis of the bone. The Haversian canals surround blood vessels and nerve cells throughout the bone and they communicate with osteocytes in lacunae through canaliculi. This unique arrangement is conducive to mineral salt deposits and storage, which gives the bone tissue its strength.

Volkmann's canals are inside osteons. They interconnect the haversian canals with each other and the periosteum. Volkmann's canals are any of the small channels in the bone that transmit blood vessels from the periosteum into the bone and that communicate with the haversian canals.

A tendon is a tough band of fibrous connective tissue that usually connects muscle to bone and is capable of withstanding tension. Tendons are similar to ligaments. Ligaments join one bone to another bone. Tendons and muscles work together to move bones.
Cartilage is a flexible connective tissue in animals, including the joints between bones, the rib cage, the ear, the nose, the bronchial tubes and the intervertebral discs. It is not as hard and rigid as bone, but it is stiffer and less flexible than muscle.
Therefore, the correct answer is option C.

The salts of magnesium and calcium forms an integral part of the skeletal system. Magnesium combines with phosphates, to form magnesium phosphate which contributes to the bone density. It forms major part of dry matter of bones. Osteoporosis is caused, due to the decrease in the density of calcium and magnesium salts in the body. It also helps in muscle contraction. 60% of the total magnesium are present in the bones.
So, the correct option is D.

Cartilage and bones are specialised connective tissue and are a part of skeletal tissue. They help the body to maintain its posture and protect internal organs.
So, the correct answer is 'Cartilage and bone'.

Intervertebral disc is present between the adjacent vertebrae in the vertebral column. Each disc is composed of fibrous cartilage and forms the fibrocartilaginous joint.
So the correct answer is 'White Fibrous cartilage'.

Epiglottis is present in throat . It is a flap that is made up of elastic cartilage. It keeps food from entering the windpipe and the lungs.
Hence , option D is correct.

Calcified cartilage is found in the pubis of the older frog. It is a modified hyaline cartilage which is hard and non-elastic due to calcium deposition. In men, it is found at the ends of long bones and in the heads of humerus and femur. It is also found in the shark vertebrae.

These two are cartilaginous bones which means they are formed by the ossification of cartilages. Sesamoid are those formed by ossification of tendons(Eg. patella). Membranous/Investing bones are the ones derived from intra membranous ossification(Eg. bones of the skull).

The patella, the largest sesamoid bone in the body, articulates only with the patellar surface of the distal femur (patellar notch). The patella rides in the tendon of the quadriceps femoris—the largest muscle of the thigh and the primary extensor of the knee.

A long bone has two parts: the diaphysis and the epiphysis. The diaphysis is the tubular shaft that runs between the proximal and distal ends of the bone. ... The wider section at each end of the bone is called the epiphysis (plural = epiphyses), which is filled with spongy bone.

The clavicle is membrane bone. It is also called a collarbone. It is a long bone, which serves as a strut between the scapula and the sternum. It is the only long bone in the body that lies horizontally. It makes up part of the shoulder and the pectoral girdle, and is palpable in all people; in people who have less fat in this region, the location of the bone is clearly visible, as it creates a bulge in the skin.

It is elastic and flexible. It forms wall of blood vessels, lungs, true vocal chords, trachea, capsule of spleen and bronchioles. It also forms sheet in ligaments. Ligaments is a modified yellow elastic fibrous tissue and connects bone to bone.

Wharton's jelly is a gelatinous substance made up of mucoid connective tissue within the umbilical cord. Its major constituents are mucopolysaccharides (hyaluronic acid and chondroitin sulfate). It is derived from extra-embryonic mesoderm. As a mucous tissue, it protects and insulates umbilical blood vessels.

So, the correct option is 'Mucoid connective tissue'.

Brown adipose cells contain a central nucleus with peripheral fat globules. It is one of two types of fat or adipose tissue found in mammals. It is especially abundant in newborns and in hibernating mammals. Its primary function is to generate body heat in animals or newborns that do not shiver. In contrast to white adipocytes, which contain a single lipid droplet, brown adipocytes contain numerous smaller droplets and a much higher number of mitochondria, which make it brown. Brown fat also contains more capillaries, than white fat, since it has a greater need for oxygen than most tissues.
So, the correct answer is option D.