Histology Flashcards
Tissue consists of a layer of cube-shaped cells.
Simple cuboidal epithelium
Location: lining the kidney tubules and the small ducts of many exocrine glands.
FUNTION: secretion and absorption
A single layer of tall rectangular cells that look like columns. Notice that the nucleus of each cell is about 2/3 of the way down from the lumen, towards the basement membrane.
Simple columnar epithelium
LOCATION: Lines the gallbladder and most of the digestive tract and most of the digestive tract organs. (Small and Large intestines)
FUNCTION: absorption and secretion.
Many layers of cells with squamous cells located at the free surface or facing the lumen.
LOCATION: the keratinized variety is located on the outer surface of the skin (epidermis).
Non-keratinized variety lines the mouth, esophagus and vagina.
Stratified Squamous epithelium
FUNTION: Protection
This tissue is not really stratified (pseudo). This tissue contains numerous goblet cells and looks like simple columnar epithelium.
This tissue is not found in the linings of the intestines or gallbladder.
The presence of cilia is an important identifying characteristic.
Pseudostatified columnar epithelium
It attaches to bones and is involved in the movement of bones at the joints.
This tissue is voluntary because we voluntarily control its contraction.
Muscle tissues
Composed of elongated cells that are not stratified.
Each cell is spindle-shaped (largest at its midpoint and tapers towards its ends)
Each cell has a single nucleus located in the middle part of the cell.
LOCATION: walls of hollow internal organs such as the bladder, stomach, intestines, uterus, gallbladder, and blood vessels.
DESCRIPTION: Long tapered fibers with a centrally located nucleus.
FUNCTION: movement of substance inside the hollow organ. (Food in the intestines, blood in the heart, etc.
Smooth Muscles
Composed of stratified fibers that are branched.
The nuclei are centrally located.
The darkly stained intercalated discs is a good indication characteristic of this tissue.
Cardiac muscle
DESCRIPTION: Branched striated fibers with a centrally located nucleus.
LOCATION: Wall of the heart.
FUNCTION: Pumps blood throughout the body, via the blood vessels.
This tissue has many collagen and elastic fibers running randomly throughout it.
The nuclei you many cells associated with this tissue can also be seen.
Areolar Connective Tissue
DESCRIPTION: Consists of collagen, plastic and reticular fibers embedded in a semifluid matrix, together with fibroblast, mast cells, plasma cells and macrophages.
LOCATION: Hypodermis (subcutaneous layer of the skin), around most organs, between muscles.
FUNCTION: Loosely binds organs together.
This tissue is connective tissue that has a fluid matrix called plasma.
LOCATION: suspected in blood plasma.
Vascular Connective Tissue (Blood)
Erythrocytes (red blood cells) DESCRIPTION: Biconcave cells that are stained pink. The thinner center of the cell is lighter than the rim.
FUNCTION: Transport respiratory gases (oxygen and C02)
Leukocytes (white blood cells) cells with an obvious, darkly stained (usually multi-lobed) nucleus.
FUNCTION: involved in immunity.
Thrombocytes (Platelets)
DESCRIPTION: darkly stained structures much smaller than erythrocytes.
FUNCTION: involved in blood clotting.
This tissue contains of numerous collagen fibers oriented in the same direction.
This produces great strength in the direction that the fibers run.
Resembles ckicken-wire. Has large area where fats are stored.
LOCATION: Subcutaneous layer of skin (Hypodermis), fatty-capsule surrounding the kidney, yellow bone marrow, and around the heart.
FUNCTION: Energy storage, insulation, protection.
Adipose conn. Tissues
Contains numerous collagen fibers oriented in the same direction.
This produces great strength in the direction that the fibers run.
DESCRIPTION: contains many collagen fibers running in the same direction. Individual fibers appear to be “wavy”.
Fibroblasts can be seen between the fibers.
LOCATION: Makes up tendons and ligaments.
FUNCTION: Attaches muscles to bones (tendons) and bone to bone (ligaments).
Fibrous Connective Tissue
This tissue has a matrix that is firm enough to bear a lot of pressure without permanent distortion. Found covering the ends of bones within our freely movable joints, where it reduces friction for the smooth articulation of the bones within the joint. Is avascular and has no nerves.
DESCRIPTION: located in spaces called lacuna, which are surrounded by a translucent matrix imterlaced with collagen fibers.
FUNCTION: Reduces friction in joints; support with flexibility.
Hyaline Cartilage Connective Tissue
This tissue has a hard matrix containing ions of calcium and phosphorus. The matrix is laid down around a dense network of collagen fibers in layers called lamellae. They resemble tree stumps.
DESCRIPTION: A network of osteons make ground bone resemble tree stumps.
LOCATION: Makes up bone of the body.
FUNCTION: Protection, Support, Mineral storage, Fat storage (yellow marrow)
Osseous Connective Tissue
Two basic types of this tissue.
–are large cells that function to conduct electrical impulses from one part of the body to another (example: from the spinal cord to the brain).
–are small cells that support the neurons in a number of different ways.
DESCIPTION: large neuron cell bodies with obvious processes (axons & dendrites) extended from them.
LOCATION: nervous system
FUNCTION: conduct electrical (nerve) impulses throughout the body.
Nervous Tissue (Nerve cell/ neuron)
Neurons
Neuroglia
A single layer of flat cells. Looks like a platter of fried eggs, “sunny side up”.
LOCATION: Air sacs (alveoli) of the lungs, lining the inside of the heart and blood vessels.
Simple squamous epithelium
FUNCTION: filtration, diffusion, osmosis.
