In the given schematic diagram of ultrastructure of a myofibril, the functional unit of muscle contraction is shown by the letter:
| 1. | A | 2. | B |
| 3. | C | 4. | D |
| 1. | It covers the external surface of the body and the internal surface of many organs. |
| 2. | The neighbouring cells are held together by cell junctions and there is very little extracellular material. |
| 3. | The epithelial cells rest on a cellular basement membrane that separates it from underlying connective tissue. |
| 4. | There is no blood vessel supplying the nutrients to the epithelial cells. |
Communication junctions found at some fusion points that allow the cardiac muscle cells to contract as a unit are called as:
1. Intercalated discs
2. Sarcolemma
3. Nodes of Ranvier
4. Motor end plates
| 1. | Fallopian tubes are lined with brush-bordered epithelium. |
| 2. | Proximal convoluted tubule of the nephron is lined by ciliated epithelium. |
| 3. | Areolar tissue is a dense, regular connective tissue. |
| 4. | Skin has dense irregular connective tissue. |
In male cockroaches, the genital pouch is bounded by:
| 1. | 9th and 10th terga dorsally and 10th sternum ventrally |
| 2. | 9th tergum dorsally and 9th and 10th sterna ventrally |
| 3. | 9th and 10th terga dorsally and 9th sternum ventrally |
| 4. | 9th and 10th terga dorsally and 9th and 10th sterna ventrally |
Tendons attach:
1. Skeletal muscle to bone
2. Bone to bone
3. Muscle to muscle
4. Smooth muscle to bone
| Statement I: | In nearly all animal tissues, specialised junctions provide both structural and functional links between its individual cells. |
| Statement II: | Cell junctions are more common in connective, muscle and neural tissue than in epithelium. |
| 1. | Statement I is correct; Statement II is correct |
| 2. | Statement I is correct; Statement II is incorrect |
| 3. | Statement I is incorrect; Statement II is correct |
| 4. | Statement I is incorrect; Statement II is incorrect |
| I: | The alimentary canal of frogs is short because they are carnivores and hence the length of the intestine is reduced. |
| II: | The liver secretes bile which is stored in the pancreas. |
| III: | Food is captured by the bilobed tongue in frogs. |