Chapter 3-Histology Yasmin L

What is histology?

Histology is the study of cells.

What is cell differentiation?

Cell differentiation is the development process that results in the formation of different type of cells.

What are the four types of tissue in the body?

1. epithelial

2. connective

3. nerve

4. muscle

What are the three general characteristics of epithelial tissue?

1. adhere closely to one another

2. no blood vessels

3. body surface or lining of body

What does avascular mean?

Avascular means without blood vessels (non-vascular.)

What are the three ways epithelial tissues are classified?

1. based on the arrangement (layering) of the cell

2. based on the shape of the cell

3. based on the cellular modifications (mostly only in columnar epithelial cells)

What are simple cells?

simple cells are cells with only one layer.

What are stratified cells?

Stratified cells are cells with multiple layers.

How do squamous cells look?

Squamous is the shape of a flat (square) cell

How do cuboidal cells look?

A cubical cell is boxy.

How do columnar cells look?

Columnar cell is a tall and skinny cell.

What are the three types of cellular modifications?

1. cillia

2. microvilli(brush border)

3. goblet(mucus-secreting)

What type of cells do you find cellular modifications on?

The type of cells that have cellular modifications are usually only present in columnar epithelial cells.

What are cilia?

Cilia has fine motile hairs and it is found on top of columnar cells.

What are microvilli?

microvilli is a finger like extension of the cell also known as brush border. It is known to increase surface area of the cell via absorption.

What are goblet cells?

Goblet cells are cells that contain mucus that is created.

Where do you find simple squamous epithelial cells?

You can find those in linings of all blood vessels, and in membrane.

Where do you find simple cuboidal cells found?

Simple cubical cells are found in the urinary tubules of the kidney, the liver, pancreas, tyriods, and other glands.

What does aden/o mean?

Aden/o means gland

Where do you find simple colonial ciliated epithelial cells?

You can find it in a woman’s fallopian tubes.

What do cilia on the fallopian tube do?

The cilia in the fallopian tubes pushes eggs from ovaries to the uterus.

Where do you find simple columnar epithelium with goblet cells?

You can find it in the stomach.

What do goblet cells in the stomach do?

They neutralize the stomach acid.

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

They are found in the intestines.

Where do you find pseudostratified columnar ciliated epiithelium with goblet cells?

Makes up the lining of the respiratory tract.

What does pseudo mean?

Pseudo means false

What does pseudostratified mean?

It is a false stratified layer when in reality it is a one layered cell.

What does cilia on the respiratory tract do?

It traps dust in the respiratory tract.

Where do you find transitional epithelium?

You find transitional epithelium in the urinary bladder.

Why is it called transitional epithelium?

It is called that because it changes shape in the bladder from enlarged to thin.

What does lumen mean?

It is the central cavity of a structure in a cell.

What are two subtypes of stratified squamous epithelium?

1. non-keratinizing (no dead layer)

2. kerutuzing (dead layer)

What is keratin?

Keratin is a hardening protein.

Where do you find keratin?

You can find keratin in hair, nails, and skin.

What are non-keratinizing stratified squamous epithelium?

Its has no dead layers of the cell.

Where do you find non-keratinizing stratified squamous epithelium?

lt is located in the oral cavity, anal canal, and vaginal canal.

What is keratinizing stratified squamous epithelium?

It is when dead cell layers are present.

Where do you find keratinizing stratified squamous epithelium?

It makes up the epidermis of the skin(outside of skin) they are dead because they aren’t surrounded by liquids.

What do all cells need to be surrounded by?

All cells need to be surrounded liquid.

What is the function of connective tissue?

The function of connective tissue is to connect and support the other issues of the body.

How are connective tissues classified?

Connective tissue is classified as type of cell, and type of intercellular matter.

What is the areolar loose connective tissue?

It has fibroblasts(collagen & elastin/ principal cell/secretes protein), macrophages (engulfs foreign agents), and mast cells(secretes histamines and creates inflammation).

What are fibroblast?

Fibroblast are cells that creates collagen and elastin.

What are macrophages?

Macrophage is a cell that engulfs foreign agents.

What are mast cells?

Cells that secrete histamine and other things that cause inflammation.

What is inflammation?

Inflammation is a reaction to dilation of blood vessels(erythema), swelling (edema/leakages) and pain.

What does erythema mean?

Erythema means redness or dilation of blood cells.

What is edema?

Edema is swelling and is when more water secretes from the blookd vessels.

What two proteins are secreted by fibroblasts?

The two proteins that are secreted by fibroblasts are collagen and elastin.

What is collagen?

Collagen is protein fibers confer strength to tissues.

What is elastin?

Elastin is protein fibers confer elasticity to the tissues.

What is adipose tissue?

Adipose tissue is a tissue filled with fat filled vesicles (storage containers)

What is the function of adipose tissue?

The function is to provide a reserve of food (for energy), insulates against heat loss, supports, and protect the organ it enclosed.

What are three common locations of adipose tissue?

1. under the skin

2. around kidney and eyeballs

3. Butocks and breast

What are two subtypes of dense fibrous connective tissue?

1. regular arranged

2. irregularly arranged

What are five places where dense fibrous connective tissue look?

1. tendons

2. ligaments

3. dura mater(enclosed brain and spinal cord)

4. fascia

5. perichondrium and periosteum

What does peri mean?

peri means around

How do regularly arranged dense fibrous connective tissue look?

They look more put together and are mostly in straight lines going one way.

How do irregularly arranged dense fibrous connective tissue look?

It is very scattered and squiggly unlike the regular.

What is special about cartilage tissue, unlike other connective tissue?

Cartilage contains no blood vessels and is an exception to the general pattern of connective tissue.

What are the three subtypes of cartillage?

1. hyaline cartilage

2. fibrocartilage

3. elastic cartilage

What are four locations where hyaline cartilage is found?

1. long bones of the body

2. front of body

3. trachea(windpipes) and larynx(voicebox)

4. surfaces of articulating bones

Where is fibrocartilage found?

They are found in the intervertebral discs(in between vertebrae).

Where is elastic cartilage found?

It is found in the external ear (pinna).

What is osteocytes?

Osteocytes is bone cell surrounded by a pocket of fluid called a lacuna.

What does a compact bone look like?

It is arranged in concentric circles called Haversian Systems.

What does spongy bone look like?

The osteocytes is arranged in spongy networks like a honeycomb.

What are osteoblasts?

Osteoblast secretes calcium mineral to form bone tissue (ossification).-the hormone Calcitonin

What is osteoclast?

An Osteoclast breaks down calcium minerals(bone respiration).-the hormone Parathyroid

What is resorption?

The process of breaking down a bone and absorbes tissue.

What is ossification?

Is when the bone forms new bone tissue from oestobasts.

What are haversian systems?

It is a cylinder system surrounded by rings.

What is diaphysis?

Diaphysis the the shaft of the bone.

What is epiphysis?

Epiphysis is the widened ends of the bone.

What is in the medullary cavity?

It is the red, and yellow bone marrow. Yellow is the ¨fat¨ or adipose tissue.

What is hemopoiesis?

The creation of blood cells in bone marrow.

What is hemopoiesis tissue?

Hematopoiesis tissue is made up of blood and lymph, also containing white and red blood cells, and platelets.

What are erythrocytes?

Eyrth-red so red blood cells that transport CO2&O2.

What is leukocytes?

Leuk-white so white blood cells and produces antibodies and interferons that inactivates foreign agents.

What is platelets?

Blood platelets produce throboplains (thrombocytes) which triggers blood clotting.

What is thromboplastin?

A protein that helps start blood clotting.

What are neoplasms?

It is an abnormal growing of tissue in some parts of the body, sometimes known as cancer.

What are benign tumors?

A benign tumor increased multiplication of tissue cells (mitosis).

What are malignant tumors?

Malignant tumors are cancers tumors that have increased multiplication of tissue cells, but these abnormal cells exhibit metastasis (migration).