Question

11.1
(i) Give two functions of the xylem tissue of plants. [2 Marks]
(ii) Which type of meristem is present at the base of leaves ? [1 Marks]

11.2
(i) X is a type of epithelium forming largest organ in human body. What is X? [2 Marks]
(ii) State one similarity between smooth muscle and cardiac muscle. [1 Mark]

11.3 Match the following. [4 Marks]
$\begin{array}{cc}\text{Type of Epithelial Tissue}& \text{Location}\\ \text{(a) Squamous epithelium}& \text{(i) Lining of kidney tubules}\\ \text{(b) Cuboidal epithelium}& \text{(ii) Skin}\\ \text{(c) Columnar epithelium}& \text{(iii) Respiratory tract}\\ \text{(d) Stratified squamous epithelium}& \text{(iv) Lining of mouth}\end{array}$

Answer 1

11.1
(i) The functions of xylem includes:
Xylem is a complex permanent tissue. It is responsible for the upward conduction of water and minerals in plants. Xylem consists of tracheids, vessels, xylem parenchyma and xylem fibres. Xylem fibres are mainly supportive in function. They provide mechanical strength to the plant.
(ii) Intercalary meristem is present at the base of leaves, above the nodes (e.g., grasses) or below the nodes (e.g., mint). Intercalary meristem helps in the elongation of stem.

11.2
(i) Skin is the largest organ in human body. It is formed from stratified squamous epithelium tissue. Stratified squamous epithelium has multiple layers of cells whereas, simple squamous epithelium has single layer of cells. [2 Marks]

(ii) Both smooth and cardiac muscle are uninucleated (both having single nucleus). Smooth muscle tissue has unbranched fibres, while cardiac has branched fibres. Both smooth and cardiac muscle tissue are involuntary in nature. Smooth muscle is spindle-shaped while cardiac is cylindrical in shape. [1 Marks]

11.3
$\bullet$ Epithelial tissue forms the protective covering of the body. And they may be present in single layer or more than one layer.
$\bullet$ If epithelial cells of skin are arranged in layers are called stratified squamous epithelium.
$\bullet$ The various types of epithelial tissue and their respective locations are mentioned below.

$\begin{array}{cc}\text{Type of Epithelial Tissue}& \text{Location}\\ \text{(a) Squamous epithelium}& \text{(iv) Lining of mouth}\\ \text{(b) Cuboidal epithelium}& \text{(i) Lining of kidney tubules}\\ \text{(c) Columnar epithelium}& \text{(iii) Respiratory tract}\\ \text{(d) Stratified squamous epithelium}& \text{(ii) Skin}\end{array}$ [4 Marks]