3.1 to 3.3 Histology Bryce LaRoche

What is Histology?

The study of tissues

What is cell differentialism?

When embryonic cells begin to synthesize different types of proteins.

What are the four types of tissues in the body

Connective tissues, epithelial tissues, muscle tissues, nerve tissues.

What are three characteristics of epithelial tissue?

They stick together, have no blood vessels, and are often found on a surface or lining of the body.

What does Avascular mean?

Without blood vessels

What are three ways epithelial tissues are classified.

The layering of the cells, the shape of the cells, and the cellular modifications of the cells.

What are simple cells?

Cells arranged in one layer.

What are stratified layers?

Cells in multiple layers.

How do squamous cells look?

Flat

How do cuboidal cells look?

Boxy

How do Columnar cells look?

Tall and skinny

What are three types of cellular modifications?

Cilia, microvilli, and goblet cells.

What type of cells do you find cellular modifications on?

They are usually found on Columnar epithelial cells.

What are cilia?

Fine motile hairs

What are microvilli?

Finger-like extrusions that increase the surface area of the cell for better absorption.

What are goblet cells?

Mucus secreting Columnar cells.

Where do you find simple squamous epithelial cells?

The alveoli of the lungs, lining of all blood vessels, the walls of the capillaries called the endothelium, and the various membranes of the body.

Where do you find simple cuboidal cells?

The urinary tubules of the kidney, liver, pancreas, thyroid, and other glands of the body.

What does Aden/o mean?

gland

Where do you find simple columnar ciliated Epithelial cells?

In the lining of women’s fallopian tubes.

What do the cilia on the fallopian tubes do?

Push eggs from the ovaries to the uterus

Where do you find simple columnar Epithelium with goblet cells?

The lining of the stomach.

What do the goblet cells in the stomach do?

Neutralize the stomach acid with mucus.

Where do you find simple columnar brush-border Epithelium with goblet cells?

The lining of the intestine

Where do you find pseudo stratified columnar ciliated Epithelium with goblet cells?

The lining of the respiratory tract.

What does pseudo mean?

false

What does pseudo stratified mean

False stratified due to the columnar cells not being all at the same height

What does the cilia in the respiratory tract do?

They trap dust

Where do you find transitional Epithelium?

The lining of the urinary bladder

Why is it called transitional epithelium?

The tissue becomes stretched and changes as the bladder fills with urine

What does lumen mean?

The cavity of a tubular organ

What are the two subtypes of stratified squamous Epithelium?

Non-keratinizing and keratinizing

What is keratin?

A hardening protein.

Where do you find keratin?

Hair, nails, skin

What are non-keratinizing stratified squamous epithelium?

Epithelial tissue made of layered and flat cells that don’t use keratin to produce layers of dead cells.

Where do you find non-keratinizing stratified squamous epithelium?

The lining of the oral cavity, anal canal, and vaginal canal

What is keratinizing stratified squamous epithelium?

Epithelial tissue made of layered and flat cells that produces layers of dead cells with keratin.

Where do you find keratinizing stratified squamous epithelium?

The epidermis of the skin.

What do all cells need to be surrounded by?

All cells need to be surrounded by a liquid.

What is the function of connective tissue?

To connect and support the other tissues of the body.

How are connective tissues classified?

Based on the type of cell or cells and based on the type of intercellular matter found between the cells.

What is areolar (loose) connective tissues?

Connective tissues with fibroblasts, microphages, and mast cells.

What are fibroblasts?

The principal type of cell that secretes proteins into the spaces between the cells.

What are macrophages?

Cells that engulf foreign agents

What are mast cells?

Cells that secrete histamines and other chemicals that cause inflammation

What is inflammation?

WHen the blood vessels dilate causing swelling, erythema, and pain in the area

What does erythema?

To turn red

What is edema?

Swelling

What two proteins are secreted by fibroblasts?

Collagen and elastic

What is collagen?

Collagen are protein fibers that add strength to tissues.

What is elastin?

Protein fibers that confer elasticity to the tissue.

What is adipose tissue?

Fat tissue

What is the function of adipose tissue?

To store food for energy, to insulate against theater loss, and to support and protect the organs it encloses

What are three common locations of adipose tissue?

Under the skin, around the kidneys and eyeballs, and around the buttocks and breasts.

What are the two subtypes of dense fibrous connective tissue?

Regularly arranged dense fibrous connective tissue and irregularly arranged dense fibrous connective tissue.

What are five places where dense fibrous connective tissue is common?

Tendons, ligaments, dura mater, fascia, perichondrium, and periosteum

What does peri mean?

Around

How do regularly arranged dense fibrous connective tissue look?

The protein fibers are arranged in parallel bundles resulting in a flat and smooth shape

How do irregularly arranged dense fibrous connective tissue look?

The protein fibers are interwoven and running in all directions.

What is special about cartilage that makes it unlike any other connective tissue?

It contains no blood vessels

What are the three subtypes of cartilage?

Hyaline Cartilage, Fibrocartilage, and Elastic Cartilage

What are four locations where Hyaline Cartilage is found?

The long bones of the body, the front of the nose, the trachea and larynx, and the surfaces of the articulating bones

Where is fibrocartilage found?

The intervertebral disks

Where is elastic cartilage found?

The external ear (pinna)

Whats an Osteocyte?

A bone cell

What does a compact bone look like?

They are arranged in concentric circles called Haversian systems (Osteons)

What does a spongy bone look like?

The osteocytes are arranged in a spongy network

What are osteoblasts?

Osteocytes that secrete the mineral calcium from the bone tissue (Ossifications)

What are osteoclasts?

Osteocytes that break down the mineral calcium (bone resorption)

What is resorption?

The breaking down of calcium

What is ossification?

The forming of bone tissue

What are haversian systems?

The circular arrangement of cells in concentric circles

What is a diaphysis?

The shaft of the bone

What is an epiphysis?

The enlarged wide end of the bone

What is in the medullary cavity?

red and yellow bone marrow

What is hemopoiesis?

Blood creating

What is hemopoietic tissue?

Blood and lymph tissues

What are erythrocytes?

Red blood cells

What are Leukocytes?

White blood cells

What are platelets?

Produce thromboplastin which triggers blood clotting

What is thromboplastin?

Thrombocytes which triggers blood clotting

What are neoplasms?

New growths called tumors

What are benign tumors?

Increased multiplication of tissue cells Mitosis

What are malignant tumors?

Tumors with increased multiplication of tissue cells that exhibit metastasis (migration)