Olympiad Test: Tissues- 3 - Class 9 MCQ

The epidermis is a keratinized stratified squamous epithelium. That is, the epidermis outermost layer consists of dead cells packed with the tough protein keratin.

The most distinctive xylem cells are the long tracheary elements that transport water. Tracheids and vessel elements are distinguished by their shape; vessel elements are shorter, and are connected together into long tubes that are called vessels. Xylem also contains two other cell types: parenchyma and fibers.

A meristematic tissue has the immense potential for division. They have a nucleus and they are full of cytoplasm. Thus, meristematic tissues are actively dividing cells. Cambium is composed of lateral meristematic cells. Hence, they show active growth. Xylem, phloem and sclerenchyma are made up of permanent tissue which is specialized and incapable of dividing.

Ligaments are the connective tissue that joins the two bones. A sprain, more commonly known as torn ligament, is damage to one or more ligaments in a joint, often caused by trauma or the joint being taken beyond its functional range of motion.

In plants, phloem tissues perform the function of conduction of food.

Phloem helps in conducting food materials. It is composed of:

• Sieve tube elements

• Companion cells

• Phloem parenchyma

• Phloem fibers

Sieve tube elements are tube-like elongated structures associated with companion cells. The end walls of sieve tube elements are perforated to form the sieve plate. Sieve tube elements are living cells containing cytoplasm and nucleus. Companion cells are parenchymatous in nature. They help in maintaining the pressure gradient in the sieve tube elements. Phloem parenchyma helps in the storage of food and is made up of long tapering cells, with a dense cytoplasm. Phloem fibers are made up of elongated sclerenchymatous cells with thick cell walls.

Xylem is a type of vascular tissue present in plants, which primarily transports water and nutrients from roots to stem and leaves.

Xylem parenchyma is the only living cell of the xylem. It comprises an element of complex tissue called the “Xylem” and is mainly involved in the storage of carbohydrates, fats and water conduction.

Apical meristem is found at the growing tips, that is root and shoot tips. These are actively dividing cells and are thus responsible for the growth of the plant lengthwise. Rapid division of meristematic cells can cause the plant to grow tall. There are several hormones like auxin which stimulate the multiplication of meristematic cells.

Adipose tissues are fat-storing tissues and are made up of adipocytes. They insulate the body. The blubber fat of the whale and the hump of the camel are both made up of adipose tissues. So, the correct answer is 'Adipose tissue'.

Sclerenchyma is long, slender cells with some or several pits with dense and lignified cell walls. These are typically found mostly in fruit walls of nuts, the coconut husk, the legume seed coat, etc.

The bone matrix contains bone minerals also known as hydroxyapatite, which consists of mainly calcium and phosphorus with trace amounts of sodium, magnesium, and bicarbonate. Fluorides, potassium and phosphorus are not found in insignificant amounts in the bone.

• Bone matrix is the intercellular substance of bone tissue consisting of collagen fibers, ground substance, and inorganic bone salts

• It is the flexible protein matrix in which minerals such as calcium and phosphorus