MLT GlobeHistopathology: Cells, tissues & basic histology – page 3
88 Histopathology MCQs on Cells, tissues & basic histology with answers and explanations.
The skin itself (cutis) is made up of which layers?
Skin consists of the epithelial epidermis and the connective tissue dermis. The hypodermis (subcutis) lies beneath and anchors the skin but is not usually counted as a skin layer.
Hepatocytes and steroid-secreting cells are rich in which organelle, responsible for lipid and steroid synthesis?
Smooth ER synthesizes lipids and steroids and detoxifies drugs. Rough ER makes proteins, lysosomes digest material and the Golgi modifies and packages products.
The laryngeal prominence ('Adam's apple') is formed by the thyroid cartilage. What type of cartilage is it?
The thyroid, cricoid and most arytenoid cartilage is hyaline. The epiglottis and corniculate cartilages are elastic.
A lower motor neuron in the spinal cord has one axon and many dendrites. It is classified as:
Motor neurons are multipolar. Bipolar neurons occur in the retina and olfactory epithelium; pseudounipolar neurons are sensory cells of dorsal root ganglia.
The epidermis of thick and thin skin is classified as which epithelium?
The epidermis is multilayered with flattened, keratinized surface cells. Simple squamous lines vessels and alveoli; transitional epithelium lines the urinary tract.
A section through a growing child's long bone shows columns of proliferating chondrocytes between epiphysis and diaphysis. This growth plate is made of:
The epiphyseal plate is hyaline cartilage whose zones proliferate, hypertrophy and calcify before replacement by bone. Fibrocartilage and elastic cartilage do not form growth plates.
Most of the stomach and intestines are lined by which epithelium?
From the stomach to the rectum the mucosa is lined by simple columnar cells specialized for secretion and absorption. The esophagus and anal canal have stratified squamous epithelium.
Which activity is NOT performed by hepatocytes?
The liver produces bile, but it is stored and concentrated in the gallbladder. Hepatocytes carry out glycogenesis, synthesize plasma proteins and store fat-soluble vitamins.
Basophilic keratohyalin granules are the defining feature of which epidermal layer?
Cells of the stratum granulosum contain keratohyalin granules that help aggregate keratin filaments. The basale is proliferative, spinosum has desmosome 'spines' and corneum consists of dead keratinized cells.
The part of a neuron that contains the nucleus and Nissl substance is called the:
The soma or perikaryon houses the nucleus and Nissl bodies (rough ER). A ganglion is a cluster of cell bodies outside the CNS; the axon hillock lacks Nissl substance.
Which site is composed mainly of smooth muscle?
Hollow viscera such as the bladder, gut and uterus have smooth muscle walls. The tongue and biceps are skeletal muscle; the myocardium is cardiac muscle.
Surface cells of the epidermis are filled with keratin and lose their nuclei. This process is called:
Keratinocytes fill with keratin and die as they move to the surface, producing a protective stratum corneum. Cilia and microvilli are features of respiratory and absorptive epithelia.
Bone formed rapidly in the fetus or at a fracture site, with irregularly arranged collagen fibres, is called:
Woven bone has randomly oriented collagen and many osteocytes; it is later remodeled into lamellar bone. Compact and cancellous describe the architecture of mature lamellar bone.
In a cartilage section, each chondrocyte lies within a small space in the matrix called a:
Chondrocytes (and osteocytes) occupy lacunae. The space of Disse lies between hepatocytes and sinusoids; Haversian canals carry vessels in bone.
The resident macrophages of the brain and spinal cord are:
Microglia are the CNS phagocytes. Kupffer cells are liver macrophages, Langerhans cells are antigen-presenting cells of epidermis, and dust cells are alveolar macrophages.
The mature bone cell that sits in a lacuna and communicates through canaliculi is the:
Osteocytes are osteoblasts trapped in mineralized matrix, connected by processes in canaliculi. Osteoblasts form bone, osteoclasts resorb it and chondrocytes are cartilage cells.
An epithelium in which all cells touch the basement membrane but nuclei lie at different levels, giving a layered look, is:
Pseudostratified epithelium, e.g. respiratory lining, appears layered but is a single layer. Transitional and stratified squamous epithelia are truly multilayered.
Which organelle contains acid hydrolases for intracellular digestion?
Lysosomes are membrane-bound vesicles with hydrolytic enzymes active at acid pH. The Golgi packages these enzymes but does not carry out digestion.
Each portal area of the liver lobule contains a:
The portal triad consists of a branch of the portal vein, a branch of the hepatic artery and a bile ductule (plus lymphatics). The central vein lies at the centre of the classic lobule.
Proximal and distal convoluted tubules of the kidney are lined by:
Renal tubules have simple cuboidal cells; the proximal tubule has a brush border. Transitional epithelium lines the renal pelvis, ureter and bladder.