Histology Flashcards
Olfaction refers to?
Sense of smell
Olfactory receptors are found where?
The roof of the nasal cavity
Olfactory receptors have long cilia.
True or false
True
For detection of smell to take place, what must happen?
The chemicals must be dissolved in mucus
Impulses from the nose are transmitted to the brain via?
The olfactory nerve
Interpretation of smell is made in what part of the brain?
The brain cortex
A cluster of taste receptor cells, make up a?
Taste bud
Taste receptor cells are also known as?
Gustatory cells
Where are taste receptors are found ?
- Tongue
- Soft palate
- Upper oesophagus
- Cheeks
- Epiglottis
Taste receptors detect 5 elements of taste perception, which are?
- Sweetness
- Sourness
- Bitterness
- Saltiness
- Savoriness(umami)
A popular myth says different regions of the tongue control specific tastes.
Is that True or False
False.
Taste is detected by any area of the tongue via?
Tongue pores
A collection of taste receptor cells male up?
A taste bud
Taste receptors communicate with the brain through?
The 7th, 9th, and 10th cranial nerves
On average, the human tongue has how many taste buds?
2000 - 8000 taste buds
The lifespan of a taste bud is ?
About 10days
The tongue has different types of papilla. Name them?
- Fungiform papillae
- Filiform papillae
- Foliate papillae
- Circumvallate papillae
The tongue epithelium comprises?
- Taste hairs
- Taste pores
- Basal cell
- Transitional cell
- Gustatory cells
The organ of corti is located on?
The basilar membrane of the cochlea
The Scala vestibuli
Scala media
Scala tympani
outer hair cells
Inner hair cells
Basilar membrane
Are parts of?
The organ of corti
The organ of corti has ______ rows outer hair cells and _____ rows of inner hair cells
3 rows of outer hair cells
1 row of inner hair cell
Inner hair cells have what shape?
Flask shaped
Outer hair cells have what shape
They are columnar
The cornea has 5 layers. Name them?
- Outer corneal epithelium
- Bowman’s membrane
- Substantia propria
- Descemet membrane
- Inner endothelium
The outer corneal epithelium is composed of?
Thin stratified squamous non-keratinized epithelium
A homogeneous amorphous layer with fine collagen that forms the basement membrane for the corneal epithelium is known as?
The Bowman’s membrane
What layer of the cornea is transparent and has its collagens arranged in alternate lamellae for light transmission
The substantia propria
The thin and homogeneous posterior limiting membrane is called?
Descemet’s membrane
The Retina extends from ______ to _____.
Optic disc To Ora serrata
The pigment layer
Lamina of Rods & Cones
External limiting membrane
Outer nuclear layer
Outer plexiform later
Inner nuclear layer
Ganglion cell layer
Lamina of nerve fibres
External limiting membrane
Are the 9 layers of ?
The Retina
The basement membrane of the pigment epithelium is known as?
Brunch membrane
Examples of photo receptors in the retina are;
Rods and Cones
A sieve-like membrane that supports rods & cones is called?
External limiting membrane
____& carries the nucleus of rods and cones?
Outer nuclear layer
____ are wider and tapers at the end (V shaped)
Cones
_____ are narrow and cylindrical
Rods
_______ shows the nucleus of bipolar , horizontal, amacrine, and Muller cells
Inner nuclear layer
______ layer consist of the synaptic area between rods and cones
Outer plexiform
Axons of ganglion cells are also called?
Nerve fibres
____ cells send signal via olfactory tract?
Mitral cells
A collection of glands that secrete hormones directly into the blood stream constitute the?
Endocrine system
_____ cells of endocrine glands are usually arranged in short cords, follicles or clusters?
Parenchymal cells
Pituitary gland
Pineal gland
Suprarenal gland
Thyroid and parathyroid glands
Are examples of what type of glands?
Endocrine glands
What gland is responsible for secretion of somatotropin(growth hormone) ?
Pituitary gland
The Neurohypophysis is also known as?
Posterior pituitary gland
Adenohypophysis is also known?
Anterior pituitary gland
The Neurohypophysis consists of?
- Pars nervosa
- Infundibulum
________ is composed of numerous parenchymal cells arranged in thick cords?
The adenohypophysis
Parenchymal cells of the adenohypophysis are classified in 2.
Name them?
- Chromophils(have affinity for colour stains granules)
- Chromophobes
Chromophils are divided into 2..
Name them?
- Acidophils
- Basophils
Acidophils are divided according to their secretory products, such as?
- Somatotrophs (secrete somatotropin)
- Mammotrophs (secrete prolactin)
Basophils are divided into 3. Name them?
- Corticotrophs (secrete corticotropin hormone)
- Tyrotrophs (secrete Thyrotropin)
- Gonadotrophs (secrete FSH, and LH)
4.
In males FSH stimulates?
Spermatogenesis
In females, FSH stimulates?
Growth of ovarian follicle and production of oestrogen
In males, LH stimulates?
Production of androgen
by Leydig cells
In females, LH stimulates?
The maturation of Corpus luteum and secretion of progesterone
Basophils and acidophils that have lost their granules, are called?
Chromophobes
Chromophobes produce hormones.
True or False?
False
Parts of the anterior pituitary include?
- Pars intermedia
- Pars tuberalis
The thin zone of basophilic cells between the pars distalis and Pars nervosa is?
The pars intermedia
The funnel shaped region surrounding the infundibulum of the Neurohypophysis is?
Pars tuberalis
What part of the adenohypophysis secretes melanocyte stimulating hormone?
Pars intermedia
A collection of unmyelinated axons, whose cell bodies are located in
1. Paraventricular
2. Supra optic nuclei are known as?
Neurohypophysis
The terminal end of axons expand and form ?
Herring bodies
The Herring bodies contain?
- Oxytocin
- ADH (vasopressin)
Oxytocin is produced by?
Paraventricular nuclei
ADH is produced by?
Supraoptic nuclei
The axons of the supraoptic and paraventricular nuclei enter the pars nervosa through?
Hypothalamo-hypophyseal tract
Supportive cells of the pars nervosa are called?
Pituicytes
Pituicytes are highly branching glial cells and they resemble resemble astrocytes.
True or false
True
Another name for pineal gland is?
Epiphysis celebri
A small, cone shaped gland that regulates the daily rhythm of body activities is called?
Pineal gland
Pineal gland is covered by connective tissue capsule that is composed of ?
Pia matter
The main cellular elements of the pineal gland are secretory cells called?
- Pinealocytes
- Neuroglial cells
Mention 3 features of pinealocytes?
- Polyhedral body
- Basophilic cytoplasm
- Prominent large nuclei
Pinealocytes give of long processes which share remains with the wall of capillaries of the 3rd ventricle
True or False
True
Pinealocytes secrete _______ during the day. And ______ during the night?
Serotonin in the day
Melatonin in the night
Melanin and melatonin are the same thing.
True or false?
False
______ hormone induces sleep due to darkness
Melatonin
_______ regulates the circadian rhythm of the body and are used in the treatment of jetlag and treatment of seasonal affective disorders (SAD)
Melatonin
Neuroglial cells are also called?
Interstitial glial cells
Pineal gland are characterised by calcified salts called?
- Corpora aranecea
- Brain sand
A bean shaped structure that secretes lymph is called?
Lymph node
______ is the point of entry for blood vessels and exit of lymph vessels in a lymph node?
Hilum
The capsule of lymph nodes are usually surrounded by?
Dense irregular connective tissues, elastic fibres and smooth muscles
- B & T lymphocytes
- Macrophages
- Reticular cells
- Plasma cells
Belong to?
Principal parenchymal cells of the lymph node
The 2 rounded areas within the cortex of the lymph node are?
- Lymphatic follicles
- Lymphatic nodules
Lymphatic nodules are composed of?
B-lymphocytes
Intermediate zones are composed of?
T-lymphocytes
The medulla of lymph nodes consists of?
Medullary sinus and medullary cords
The region between the cortex and medulla in lymph nodes are called?
Paracortex
Mention the functions of lymph nodes
- Production of lymphocytes for immunity
- Phagocytosis
- Antibody production
______ is the largest lymphoid organ in the body?
Spleen
The spleen has 2 major subdivisions?
White pulp
Red pulp
White pulp shares relations with arterioles, while red pulp shares relations with?
Venous sinusoids
The spleen has open and closed circulation.
True or false?
True
_______ is a bilobed lymphoid organ found in the mediastinum?
Thymus
In the thymus, thymocytes are responsible for?
Dark appearance of the cortex
The blood-thymic barrier is formed by?
Reticular cells surrounding capillaries in cortex of thymus
Epithelial reticular cells in the medulla are arranged concentrically to form?
Thymic (Hassal’s) Corpuscles
MALT means:
Mucosa Associated Lymphoid Tissue
BALT means:
Bronchial Associated Lymphoid Tissue
GALT means:
Gut Associated Lymphoid Tissue
MALT by definition refer to?
Aggregation of lymphocytes present in the mucosa of some organs
Tonsils are part of MALT.
True or False
True
