Test: Epithelial Tissue - 2 - NEET MCQ

Merocrine glands — cells secrete their substances by exocytosis (e g mucous and serous glands) Also (e.g., mucous and serous glands). Also called "eccrine".

The term eccrine is specifically used to designate merocrine secretions from merocrine secretions from sweat glands (eccrine sweat glands)

Merocrine glands have primary functions:

Thermoregulation: sweat cools the surface of the skin and reduces body temperature. This cooling is the primary function of sensible perspiration, and the degree of secretory activity is regulated by neural and hormonal mechanisms. When all of the merocrine sweat glands are working at maximum, the rate of perspiration may exceed a gallon per hour, and dangerous fluid and electrolyte losses can occur For this reason athletes in electrolyte losses can occur. For this reason athletes in endurance sports must pause frequently to drink fluids.

Compound tubuloalveolar glands are a combination of the alveolar and tubular glands and have a compound ductwork system, as well as both branching tubular and alveolar gland structures present in the salivary glands and active mammary glands.
Hence, Active mammary glands are Compound tubuloalveolar glands.

Simple branched alveolar glands have a simple duct and branched alveolar sacs. The oil-producing sebaceous glands in your skin, as well as the mucous secreting glands in your stomach that protect your stomach lining from the highly acidic gastric juices, are both examples of simple branched alveolar glands.

• Type: Simple coiled tubular

• Simple Coiled Tubular Structure: Sweat glands are classified as simple coiled tubular glands. This means that they have a single duct that is coiled in structure, allowing for the secretion of sweat.


• Function: Sweat glands play a crucial role in thermoregulation by producing sweat, which helps to cool the body down when it is exposed to heat or during physical exertion.


• Location: Sweat glands are found all over the body, with the highest concentration in areas such as the palms, soles of the feet, and underarms.


• Composition: Sweat glands are made up of epithelial cells that secrete a mixture of water, electrolytes, and other substances to help regulate body temperature.

• Understanding the structure of sweat glands as simple coiled tubular glands is essential in comprehending their function and importance in the human body's thermoregulation process.

Ependyma is the thin epithelium lining in the ventricles of the brain and the central canal of the spinal cord. These are ciliated simple columnar epithelium cells. These are involved in the production of cerebrospinal fluid (CSF).

The retinal pigment epithelium (RPE) is a single layer of post-mitotic cells, which functions both as a selective barrier to and a vegetative regulator of the overlying photoreceptor layer, thereby playing a key role in its maintenance.

• Description: This type of epithelium consists of multiple layers of cells. The outermost layer is squamous (flat) while the innermost layer is cuboidal (cube-shaped).


• Function: Provides protection against mechanical stress, pathogens, and chemical damage.


• Location: Found in areas of the body that experience wear and tear, such as the skin, esophagus, and vagina.


• Characteristics: Cells in the outer layers are constantly being shed and replaced by cells from the inner layers to maintain the integrity of the epithelium.


• Examples: The epidermis of the skin is a classic example of stratified squamous epithelium.

Bronchioles are the passageways by which air passes through nose or mouth to the alveoli of the lungs. They are branches of the bronchi. Bronchioles are around 1 mm or less in diameter and their walls consist of ciliated or non-ciliated cuboidal epithelium and also columnar epithelium and some smooth muscle.
Thus, the correct answer is the option (D).

Ciliated columnar epithelium have cilia on their free surface and occurs in the inner surface of hollow organs like fallopian tubes (oviducts), uterus and most of the respiratory tract.

• Innermost Layer: In Transitional Epithelium, the innermost layer is Cuboidal.


• Resting on Connective Tissue: This innermost layer rests on the underlying connective tissue.

Transitional epithelium is a type of stratified epithelial tissue found in areas that need to stretch and expand, such as the urinary bladder. The cells in transitional epithelium can change shape from cuboidal to squamous depending on the degree of distension in the organ. This allows the tissue to accommodate changes in volume without tearing. The innermost layer being cuboidal provides flexibility and the ability to change shape as needed.

The sebaceous gland is lined with a cuboidal stratified epithelium, that has continuity with external root sheath of hair follicle. The epithelium of sebaceous gland is modified and along it's base is a row of cuboidal cells.

The parotid gland, a large salivary gland, is one of them. Several epithelial types are found in the duct system of the parotid. The smallest ducts, which are embedded in the secretory tissue (intralobular ducts), are lined by stratified cuboidal or columnar epithelia.

• Connect the Epithelial cells: Desmosomes are cell structures that connect adjacent epithelial cells, providing strength and stability to tissues.

Choroid of eye is lined by cuboidal epithelium. Simple cuboidal epithelia are a type of epithelium that refers to a single layer of cubelike cells. These cuboidal cells have large, spherical and central nuclei. Simple cuboidal epithelia are found on the surface of ovaries, the lining of nephrons, the walls of the renal tubules, and parts of the eye and thyroid. 
So, the correct answer is 'Cuboidal epithelium'

• Oviduct: The ciliated epithelium in the oviduct helps in the movement of the egg from the ovary to the uterus. The cilia create a wave-like motion that propels the egg forward.



• Trachea: The trachea is lined with ciliated epithelium that helps in the movement of mucus and debris out of the respiratory tract. The cilia sweep the mucus and particles upwards towards the throat where they can be coughed out or swallowed.



• Uterus: The lining of the uterus also contains ciliated epithelium. The cilia in the uterus help in the movement of the fertilized egg towards the uterine cavity for implantation.



• All of above: Therefore, the correct answer is 'All of above' as ciliated epithelium is found in the oviduct, trachea, and uterus.

The brush border increases a cell's surface area is a trait which is especially useful in absorptive cells. Cells that absorb substances need a large surface area in contact with the substance to be efficient. A brush border is a name for the microvilli-covered surface of simple cuboidal epithelium and simple columnar epithelium cells found in certain locations of the body. 
The convoluted portion of the vertebrate nephron that lies between Bowman's capsule and the loop of Henle and functions especially in the resorption of sugar, sodium and chloride ions and water from the glomerular filtrate, called also proximal tubule.

The epithelium of retina and thyroid glands is made up of simple cuboidal cells, which are a single layer of small, cube-shaped cells with a centrally located nucleus, and has major functions in secretion and absorption.
So, the correct answer is 'Only cuboidal cells'.

Epithelial tissues line the cavities and surfaces of structures throughout the body. Many glands are made up of epithelial cells. Functions of epithelial cells include secretion, selective absorption, protection, transcellular transport and detection of sensation. Epithelial layers contain no blood vessels, so they must receive nourishment via diffusion of substances from the underlying connective tissue, through the basement membrane. They make a definite layer.

Marcello Malpighi, (1628-1694), Italian physician, anatomist, botanist, histologist and biologist developed methods to study living things by using the newly invented microscope to make a number of important discoveries about living tissue and structures, and initiated the science of microscopic anatomy.

The tessellated epithelium is present in the endothelium. Squamous epithelium having only one layer, such as in endothelium, mesothelium, and pulmonary alveoli are also called pavement epithelium or tessellated epithelium.

Hence the correct option is B.

• Lipoprotein: Lipoprotein molecules are not a major component of the Basel membrane of epithelium tissue.


• Polypeptide: Polypeptides are not the main constituent of the Basel membrane of epithelium tissue.


• Mucopolysaccharide: Mucopolysaccharides are one of the key components of the Basel membrane of epithelium tissue.


• Mucopolysaccharide and Glycoprotein: The Basel membrane of epithelium tissue is primarily composed of a combination of mucopolysaccharides and glycoproteins.

Therefore, the correct answer is option D, which states that the Basel membrane of epithelium tissue is composed of mucopolysaccharide and glycoprotein. These components provide structural integrity and support to the epithelial cells, helping them carry out their functions effectively.

• Cuboidal Epithelium: The germinal epithelium is primarily composed of cuboidal epithelial cells. These cells are cube-shaped and are responsible for covering the surface of the ovary.

• The germinal epithelium is a type of epithelial tissue that covers the surface of the ovary.


• This epithelium plays a crucial role in the development of ovarian follicles and the release of eggs during the menstrual cycle.


• Cuboidal epithelial cells are well-suited for this function as they provide a protective barrier while also allowing for the exchange of nutrients and waste products.


• Overall, the composition of cuboidal epithelium in the germinal epithelium ensures proper ovarian function and reproductive health in females.

• Stratified squamous epithelium: The inner lining of the vagina is composed of a layer of stratified squamous epithelium. This type of epithelium is well-suited to withstand friction and stretching that occurs during sexual intercourse and childbirth.

• Stratified squamous epithelium is composed of multiple layers of flat cells that are stacked on top of each other.


• This type of epithelium provides protection against abrasion and mechanical stress.


• The presence of stratified squamous epithelium in the vagina helps to maintain the integrity of the vaginal lining and protects it from damage.


• Additionally, this type of epithelium allows for the secretion of mucus and other substances that help to keep the vagina moist and lubricated.

• Cuboidal epithelium: The secretory part of sweat glands is composed of cuboidal epithelium. Cuboidal epithelial cells are cube-shaped and have a single layer. These cells are specialized for secretion and absorption.

• The cuboidal epithelium is well-suited for the secretory function of sweat glands as it allows for efficient secretion of sweat.


• These cells have abundant mitochondria to provide energy for the secretion process.


• The cuboidal shape of the cells allows for a larger surface area for secretion compared to squamous epithelium.


• Cuboidal epithelium also helps in regulating the composition of sweat by selectively secreting ions and water.

The zygote divides incessantly to form numerous cells which undergo gastrulation and forms three germ layers. In-growth from an epithelial surface leads to the formation of glands. This invagination starts after formation of germ layers. Endoderm also forms the lining cells of all the glands. The surface ectoderm develops into the epidermis, hair, nails, the lens of the eye, sebaceous glands, cornea, tooth enamel, the epithelium of the mouth and nose. The mesoderm forms adrenal glands.

So, the correct answer is option D

• Transitional epithelium: The inner lining of the urinary bladder is composed of transitional epithelium. This type of epithelium is unique in that it can stretch and contract as the bladder fills and empties.


• Function: Transitional epithelium allows the bladder to expand to hold urine and contract to expel it, providing flexibility and protection to the bladder wall.


• Appearance: Transitional epithelium is made up of multiple layers of cells that change shape from rounded to flattened as the bladder stretches. This allows the bladder to accommodate varying volumes of urine.


• Location: Transitional epithelium is also found in other parts of the urinary system, such as the ureters and renal pelvis, where its stretchable properties are essential for proper function.

• Tubular Glands: These glands have a long, tube-like structure that secretes substances onto the skin surface. They are commonly found in amphibians like frogs.


• Simple Alveolar Glands: These glands have a sac-like structure that secretes substances directly onto the skin. They are simple in structure and function.


• Compound Alveolar Glands: These glands have a more complex structure with multiple sac-like units that secrete substances onto the skin surface. They are more specialized in their secretion process.


• Compound Tubular Glands: These glands have a branching, tubular structure that secretes substances onto the skin surface. They are more complex in structure compared to simple tubular glands.

• The correct answer is B: Simple Alveolar Glands.


• In frogs, simple alveolar glands are the most common type of cutaneous gland found on their skin surface.


• These glands play a crucial role in maintaining the skin's hydration and protection against external environmental factors.

Brush border refers to the microvilli covered surface. The gall bladder is lined by a single layer of columnar epithelium with microvilli. Microvilli provide the extra surface area which increases the absorption of fluid and nutrients from digested food. 

Ciliated columnar epithelial is present in the intestinal linings. The outer surface of the intestine has hair-like structures called cilia. These help to push mucus out and clear it.  

When epithelium cells are arranged in a pattern of multiple layers, they are called stratified ( strata means many layer) squamous epithelium. They are found in skin where they serve the purpose of protection. 

Apocrine glands are the glands which secretes their secretion by packaging them into a vesicles bud off from the plasma membrane. Lactating breast is an example of apocrine gland.
If the secretion of the cells is excreted via exocytosis from secretory cells into the epithelial-walled ducts and then onto a bodily surface or into lumen are merocrine cells (E.g., salivary glands, pancreatic glands).
In holocrine secretions, the secretions are produced in the cytoplasm of the cell and are then released by the rupture of the plasma membrane, which destroys the cell resulting in the secretion of the product into the lumen. (E.g., sebaceous gland).
So, the correct answer is option B.