Histology II: special, circulatory and nervous Flashcards
What two main groups is special histology divided into?
Compact (or solid) organs and tubular (or hollow).
Another term for “solid” organs?
Parenchymatous organs.
What is the thymus?
is a specialized primary lymphoid organ of the immune system.
The thymus gland is in the chest between the lungs.
It makes white blood cells (T lymphocytes).
What surrounds a solid organ?
A capsule made of dense connective tissue.
Describe the structure of the organ capsule.
Continuous with trabeculae or septa that together form the stroma.
Define stroma.
supportive tissue of certain types of organs
consists of dense and loose connective tissue divisions called lobes and lobules
Define parenchyma.
The functional tissue making up the specific morphological and functional part of an organ and distinguished from the connective and supporting tissue.
What is spleen parenchyma called?
Pulp.
Define anatomical “lobe”.
A clear anatomical division or extension of an organ e.g. the hemispheres of the brain, lobes of the lungs and liver, kidneys.
Define lobule.
A lobule is a much smaller unit of a lobe, and it’s clear division is only visible using a microscope.
In some organs the parenchyma is divided into what two parts?
The outer cortex and the inner medulla.
Name 5 organs with an outer cortex and an inner medullary cavity.
Kidneys, adrenal glands, lymph nodes, ovaries, thymus.
A gross division of nervous tissue within the brain and spinal cord is what?
White and gray matter.
Upon gross inspection, what is a dividing feature of cortex versus medulla?
Cortex is darker, medulla lighter.
What is the connective tissue surrounding the testes and ovaries called?
Tunica albuginea.
What is the connective tissue surrounding the brain and spinal cord called?
Meninges.
What is the connective tissue surrounding cartilage called?
Perichondrium
What is the connective tissue surrounding bones called?
Periosteum.
What is the connective tissue surrounding muscle fiber bundles called?
Perimysium.
What is the connective tissue surrounding nerves called?
Perineurium.
Describe the structure of tubular organs simply.
Structural elements/tissues surrounding a central lumen.
Give some examples of tubular organs.
Intestinal-, respiratory-, urinary- and genital ducts, blood and lymph vessels.
Name for thickest layer of tubular organ wall.
Tunics or coats (tunica).
The tunicas of tubular organ walls have sublayers called?
Lamina or stratum.
Tubular organ walls consist commonly of how many tunics?
3
Name two subtypes of tubular organs.
Organs with connections to outside the body (intestinal- and respiratory canal, genital ducts)
and closed network organs (blood and lymph vessels).
Name the 3 main layers of duct-like tubular organs.
Tunica mucosa which commonly consists of 4 layers
Tunica muscularis which consists of two layers
Tunica adventitia or also called serosa
Name the 4 sublayers to tunica mucosa.
epithelium
lamina propria mucosae
lamina muscularis
lamina submucosa
Name the 3 main layers to closed network tubular organs.
Tunica intima (interna) Tunica media Tunica adventitia (externa)
Name the 2 SUBlayers to closed network tubular organs.
endothelium
subendothelial layer
What does serosa consist of?
Serous membrane that consists of a simple squamous epithelium (mesothelium), and a small amount of underlying connective tissue.
What is the main difference between serosa and adventitia?
Serosa covers the organs in the body cavities whereas adventitia attaches the organ to the surrounding tissues.
Which part of the digestive tract has no serosa, only adventitia as an outer layer?
The esophagus has adventitia because it is not covered by peritoneum.
