General Histology Flashcards
An ____________ is a specialized group of microtubules found in cilia and flagella arranged in a 9+2 pattern.
Axoneme
____________ are required for the development of cilia and are derived from centrioles.
Basal bodies
The presence of _____________ by the 8th week can determine that the sex of an embryo is female.
Barr bodies
_________ are unusually long microvilli that are only found in the epididymis and inner ear.
Stereocilia
Protein and RNA synthesis occur in all cell cycle phases except _________.
Mitosis
What are the steps of the interphase of a cell?
G1 -> S (DNA synthesis) -> G2
What are the phases of mitosis?
Prophase -> metaphase -> anaphase -> telophase
A _________ is a beltlike junction that completely seals off intercellular space.
Tight junction (zonula occludens)
A __________ is a beltlike junction that leaves a small intercellular space between cells.
intermediate junction (zonula adherens)
A ________ provides localized adhesion between adjacent cells.
desmosome (macula adherens)
What type of adhesion is seen in the epithelium of oral mucosa?
Hemidesmosome
_________ enable the passage of fluids, ions and small molecules between cells.
Gap junctions
What is a pemphigus or pemphigoid?
Pemphigus - autoimmunity agains desmosomes
Pemphigoid - autoimmunity against hemidesmosomes
Where is the thinnest epithelium in the oral cavity?
Sublingual mucosa
What are the three layers of the basement membrane?
From epithelium -> CT
- Lamina lucida
- Lamina densa (basal lamina) - Type IV collagen
- Reticular lamina - type III collagen
Most CT originates from the ___________.
mesoderm
*some in head/neck from neural crest ectoderm
Where is regular dense CT found?
Tendons, ligaments, aponeuroses
What is the most common cells in CT?
Fibroblasts
_________ secrete through ducts. _________ secrete into the blood.
Exocrine; endocrine
Hormones are secreted through _________ glands.
endocrine
________ secretions are watery. ________ secretions are viscous.
Serous; mucous
T/F: Serous glands (parotid) have well-developed intercalated and striated ducts that modify their serous secretions.
True
Mucous glands do not
What gives the striated appearance of the striated ducts in glands?
Many elongated mitochondria
In salivary glands, the intercalated duct is lined with ________ epithelium. The terminal excretory duct is lined with ______ epithelium.
simple cuboidal; pseudostratified columnar
T/F: Cartilage is avascular.
True
Blood supply from perichondrium
Cartilage is composed of __________ residing in a lacunae.
chondrocytes
What type of collagen is in the cartilage matrix?
Type II
Perichondrium covers all cartilage except…
Fibrocartilage, articular cartilage of joints, and nasal/costal cartilage
T/F: The perichondrium consists of an inner fibrous layer and outer cellular layer.
False
Inner cellular and outer fibrous
What is the difference between interstitial and appositional growth?
Interstitial - cartilage forms within existing cartilage
Appositional - new cartilage forms on surface (must have perichondrium)
________ makes up the articular disc of the TMJ.
Fibrocartilage
________ is the precursor for bone in endochondral bone formation.
Hyaline cartilage
Osteoid, uncalcified bone matrix, is composed of _________.
type I collagen and ground substance
_________ are the vascular tunnels within bone keeping osteocytes properly nourished.
Canaliculi
An increase in which enzyme in osteoblasts and matrix vesicles pushes the mineralization of bone?
Alkaline phosphatase
Flat bones of skull, maxilla, mandibular body, and clavicle are all formed through __________.
intramembranous ossification
Long bones, vertebrae, and the mandibular condyles are formed through ___________.
endochondral ossification
T/F: Appositional growth only occurs in endochondral bone.
False
Appositional - both
Interstitial - only endochondral
In cortical (compact) bone, Haversian systems (osteons) are connected by ____________.
Volkmann’s canals
In ___________ bone, lamellae are arranged in thin spicules called trabeculae.
cancellous (spongy)
_________ contains fat cells and is the primary marrow type in the mandible and maxilla.
Yellow marrow
_________ is found in the mandibular ramus and condyles. It contains hematopoietic cells.
Red marrow
Osteoclasts reside in resorption bays known as ___________.
Howship’s lacunae
____________ stimulates osteoclastic bone resorption.
Parathyroid hormone (PTH)
__________ decreases blood calcium leading to less osteoclastic activity.
Calcitonin
________ joints are immovable. _________ joints are fully movable joints.
Synarthrosis; diarthrosis
The articular cartilage of synovial joints is typically a layer of hyaline cartilage except for which two examples….
Knee and TMJ - fibrocartilage
The ________ produces synovial fluid.
synovial membrane
T/F: Neurons are actively dividing.
False
Do not divide
T/F: CNS nervous tissue is derived from neural tube ectoderm.
True
CNS - neural tube ectoderm
PNS - neural crest ectoderm
T/F: Dendrites conduct info to the cell body, axons conduct info away from the cell body.
True
What cells are the building blocks for the BBB, regulate vasoconstriction/dilation and communicate via gap junctions using calcium?
Astrocytes
________ secrete CSF.
Choroidal cells
T/F: There is only one neuron per Schwann cell.
True
T/F: Chemical signals are conducted through gap junctions.
False
Electrical signals
T/F: C fibers are myelinated.
False
What is contained in the serum of blood?
Water, albumin, globulins
Not fibrinogen or clotting factors
What is the hematocrit?
The percentage of erythrocytes in blood
Males - 45%
Females - 40%
Platelets are derived from what cells?
Megakaryocytes
How is the amount of erythrocytes destroyed per day calculated?
Amount of bile pigment excreted by the liver
Where in the circulation does the greatest drop in blood pressure occur?
Transition from arteries to arterioles
In larger arteries there are more ________ fibers, while in smaller arteries there are more _________ fibers.
elastic; smooth muscle
The ___________ is the innermost layer of blood vessels.
tunica intima
composed of endothelium (simple squamous)
Which white blood cell does not share a precursor cell?
Macrophage
Monocyte until it leaves the blood
The ________ is composed of both smooth muscle and elastic fibers. It is much thicker in arteries.
tunica media
The ________ is the outermost layer and is much thicker in veins.
tunica adventitia
The _______ is the thickest portion of the heart and contains cardiac muscle.
myocardium
Which arteries would be categorized as elastic and would contain a vasa vasora?
BIG arteries (aorta, pulmonary arteries and branches)
The _________ directly affect arterial blood pressure.
arterioles
T/F: Bradycardia describes a high HR (above 100 BPM).
False
Tachycardia - over 100 bpm
Bradycardia - under 60 bpm
T/F: Lymph is pumped through its vessels.
False
T/F: The majority of the bodies lymph is drained through the right subclavian vein.
False
Thoracic duct at left subclavian vein
Which lymphatic nodules are nonencapsulated and subepithelial?
Pharyngeal tonsils and Peyer’s patches
Where are B cells and T cells distributed in the lymph nodes?
B cells in the outer cortex and inner medulla
T cells in the paracortex
B cells mature in _________.
bone marrow
T cells mature in the _________.
thymus
T/F: The spleen develops from the primitive gut.
False
Mesenchymal cells from primitive stomach
T/F: In the spleen, the white pulp contains B cells and the PALS (has T cells).
True
What is contained in the red pulp of the spleen?
Erythrocytes, macrophages, lymphocytes
The pituitary gland is attached to the hypothalamus via the _________.
infundibulum
What provides blood to the pituitary gland?
Inferior and superior hypophyseal arteries (via ICA)
T/F: ADH and oxytocin are produced in the posterior pituitary.
False
Produced in hypothalamus, stored in post pituitary
What are the effects of PTH?
Increase in blood Ca+, bone resorption
The ________ regulates the sleep-wake cycle.
pineal gland
What is the acronym for the zones of the adrenal cortex?
GFR
G(lomerulosa) - salt
F(asiculata) - sugar
R(eticularis) - sex
The alveolar ducts and sacs contain __________ epithelium, while the alveolar septa have __________ epithelium.
simple cuboidal; simple squamous
The terminal bronchioles have __________ epithelium.
simple columnar
T/F: Type II cells cover the majority of the alveolar surface and produce surfactant.
False
Do produce surfactant but cover much less than Type I
T/F: The esophagus is innervated by CN X.
True
_______ cells secrete pepsinogen in the stomach.
Chief
_______ cells secrete HCl and intrinsic factor in the stomach.
Parietal cells
__________ cells secrete gastrin in the stomach.
Enteroendocrine (G) cells
The stomach and small intestine are lined with __________ epithelium.
simple columnar
Where is the Myenteric (Auerbach’s) plexus located?
Muscularis externa of small intestine
T/F: Submucosal glands of Brunner are only found in the duodenum.
True
T/F: Peyer’s patches are only found in the ileum.
True
How is the large intestine innervated?
CN X to ascending and transverse colon
Pelvic splanchnic nerve to descending and sigmoid colon
The portal triad consists of _________.
hepatic artery, portal vein, bile duct
T/F: Hepatocytes are often bi-nucleate (tetraploid).
True
_______ are adipocytes in the space of Disse. They store vitamin A in the liver.
Ito cells
Elevated serum bilirubin results in _________.
jaundice
Bile is transported from the liver to the gall bladder via _________ and from the liver to the duodenum via _________.
cystic duct; common bile duct
T/F: In the biliary tree, both blood and bile move from central vein -> portal canal.
False
Blood moves opposite
T/F: An increase in CCK, secretin, or gastrin will increase biliary flow.
True
T/F: In the kidneys, pyramids are found in the cortex.
False
Medulla
What kidney components are found in the cortex?
Glomerulus and bowman’s capsule; proximal and distal tubules
The __________ is a thick connective tissue capsule that covers the testis.
tunica albuginea
T/F: Seminiferous tubules are the sites of spermatogenesis.
True
Where is sperm stored?
epididymis
T/F: Sertoli cells produce testosterone.
False
Leydig - testosterone
Sertoli - testicular fluid
What are the four components of the spermatic cord?
- Ductus (vas) deferens
- Testicular artery and veins
- Lymph vessels
- Autonomic nerves
What is the route of sperm?
seminiferous tubules -> rete testis -> efferent ductules -> ductus epididymis -> vas deferens -> ejaculatory duct
The two dorsal sections of erectile tissue are called ________.
corpora cavernosa
The ventral section of the penis with the urethra is termed _______.
corpus spongiosum
The _________ is the longest section of the fallopian tubes (oviducts) and is the site of fertilization.
ampulla
T/F: The endometrium of the cervix is shed during menstruation.
False
Just of uterus
T/F: Milk is produced by both merocrine and apocrine secretion.
True
T/F: Lactation is under the control of the pituitary and hypothalamus.
True
What is the pneumonic for epidermal layers?
Inner->outer
Bad Sprinters Get Leg Cramps
Basale, Spinosum, Granulosum, Lucidum, Comeum
The basement membrane connects the epidermis and dermis of the skin via _________.
hemidesmosomes
What is the function of Langerhans and Merkel cells?
Langerhans - antigen-presenting
Merkel - touch
_________ detect stretch and heat on the skin.
Ruffini endings
_________ detect pressure and vibration.
Pacinian corpuscles
_________ detect light touch on the skin.
Meissner’s corpuscles
T/F: Apocrine glands produce sweat and are found in the entire body.
False
Odorless secretion, only in axilla, nipple, genitalia, etc.
Sympathetic
_________ is the watery fluid within the anterior and posterior chambers of the eye.
Aqueous humor
________ is the transparent watery gel within the vitreous chamber.
Vitreous humor
T/F: The cornea is the outermost part of the eye.
True
Which part of the eye gives the white color?
Sclera
The _______ of the eye contains smooth muscle and does lens accommodation.
ciliary body
The _____ of the eye contains smooth muscle for pupil dilation.
Iris
Also gives the eye its color
T/F: Rods are sensitive to light, cones are sensitive to color.
True
The ______ is in the very center of the macula lutea and has the sharpest vision.
fovea
