Science Do as directed; [Bio-1 M]

Columnar epilthelium has pillar-like cells.

Ligament connects two bones together at joints.

The main components of xylem are:

1. Xylem tracheids,
2. Xylem vessels,
3. Xylem parenchyma,
4. Xylem fibres.

1. Xylem tracheids and xylem vessels are responsible for the conduction of water and minerals because they are elongated tubular channels with wide lumen.
2. Xylem tracheids possesses pits with pores and vessels possess perforated plates through which they are able to conduct water and minerals from one cell to the another.

Lignin is deposited in the cell wall of sclerenchyma.

Collenchyma tissue is irregularly thickened at the corners due to the depositon of pectin and cellulose.

It is found in the alveoli of lungs and blood vessels.

Meristematic tissues are found in apical, intercalary and lateral positions in plants.

Cardiac muscle cells are located in the walls of the heart, appear striated, and are under involuntary control. Smooth muscle fibers are located in walls of hollow visceral organs, except the heart, appear spindle-shaped, and are also under involuntary control.

Smooth muscle is found in the walls of hollow organs throughout the body. Smooth muscle contractions are involuntary movements triggered by impulses that travel through the autonomic nervous system to the smooth muscle tissue. The arrangement of cells within smooth muscle tissue allows for contraction and relaxation with great elasticity. The smooth muscle in the walls of organs like the urinary bladder and the uterus allow those organs to expand and relax as needed. The smooth muscle of the alimentary canal (the digestive tract) facilitates the peristaltic waves that move swallowed food and nutrients. In the eye smooth muscle changes the shape of the lens to bring objects into focus. Artery walls include smooth muscle that relaxes and contracts to move blood through the body.

When many cells togetherly comes there the tissue forms.

 Parenchyma tissues are the most abundant tissues found in plants.

Tendon is a form of connective tissue.

The cells of bones are called osteocytes. Bone cells are embedded in a hard matrix that is composed of calcium and phosphorus compounds.

The main function of vascular tissues is to transport water and food in the plant. The Xylem is known to conduct water and Phloem conducts food in the form of sugars.

The main function of parenchyma is to provide support to the plant and also store food.

WBC protects our body against infections.

RBC acts as a transportor of oxygen and carbon dioxide as it contains respiratory pigment called haemoglobin.

Blood platelets help in clooting of blood at the site of injury.

Stomata are tiny pores present on the leave’s surface which help in the exchange of gases and in transpiration.

Synapse is the junction between the terminal part of one axon and the dendrite of the adjacent neuron. Synapses helps in the transmission of impulses from one neuron to another.

A permanent tissue is a group of cells which temporarily or permanently cease to divide have assumed a definite form and size.

The other name of cork cambium is phellogen.

Collenchyma is the simple tissue that provides flexibility to soft aerial plant parts to withstand against winds.

The tissue of a leaf that is found in between upper and lower epidermis is the mesophyll.

Companion cells are found associated with sieve tubes and helps in conduction of food.

Goblet cell is a simple columnar epithelial cell which is modified to secrete mucus. It is seen in the intestine and other parts of the alimentary canal.

Stomata are tiny pores present on the leave’s surface which help in the exchange of gases and in transpiration.

Division of labour is adaptation of different parts of an organism to carry out different functions.