write short notes on any four of the following: collenchyma, sclerenchyma, glandular epithelium, connective tissue, cardiac muscle.
Answers
Explanation:
Parenchyma
Living tissues with thin cell wall with central vacuole and dense cytoplasm. Parenchyma cells are located in the soft parts of the plants such as pith and cortex.
Sclerenchyma
These are dead tissues which have thick cell wall due to deposition of lignin. They are generally located in the leaf veins, hard coverings of the seeds and can also be found surrounding the vascular bundle.
Collenchyma
Living tissues which have an elongated shape and thick cell wall in the corner. Collenchyma tissue can be located in the leaf stalks, below the epidermis, etc.
Epithelial tissues
Epithelial tissues are covering or protective tissues in the animal body. Almost all organs and cavities are covered by Epithelium.
Answer:
Collenchyma: Collenchyma is a living tissue with elongated cells and irregularly thickened corners. Schleiden was the one who created the phrase. It gives the plants flexibility and mechanical support. There is a small amount of intercellular space. Plants (leaf and stem) can be bent easily without breaking.
Sclerenchyma: The tissues are dead, causing the plant to be stiff and rigid (eg. Husk of coconut). They are structurally long and narrow. Due to the presence of lignin, the cell walls are thick. They don't have enough intercellular space. These tissues can be found in the stem, the coating of seeds, nuts, the veins of leaves, and the vascular bundles.
Explanation:
Glandular epithelium: Glandular epithelium is an epithelial tissue that protects our body's glands (both exocrine and endocrine). Secretion is their primary function. Both endocrine and exocrine glands secrete through the glandular epithelium, which is made up of unique cells known as goblet cells.
Connective tissue: The body's connective tissue protects and supports it. The cells are loosely spaced and encased in a matrix that connects them. It's possible that the matrix be jelly-like, fluid, thick, or hard. Matrix properties vary depending on the function of the connective tissue in question.
Cardiac muscle: The heart's muscles are involuntary and are referred to as cardiac muscles. The cells are uninucleate, cylindrical, and branching. Throughout life, the heart muscles contract and relax in a cyclic pattern.