Chapter 4 Histology Lecture notes

(Only adding new stuff from lecture here if need old review go to lab histology notes)

Histology

Study of tissue

Tissue

Has ECM and is made up of cells related in structure and function

Four types of tissues

Epithelial tissue, connective tissue, muscle tissue, nervous tissue

ECM

Extracellular matrix

Functions of ECM

Provide tissue with tensile strength, Directs cells to proper positions

2 Main components of ECM

Ground substance and protein fibers

Ground substances

Makes up most of ECM made of water nutrients etc

Protein Fibers

Gives cell elasticity 25% of all proteins in the body

Transitional Epithelium

Only found in urinary system, can change its shape to contain more urine

Epithelial tissue functions

Protection from physical damage internal damage and thermal damage

Endocrine glands (has no duct)

Secret hormones straight into the blood stream, Has major affects throughout the body

Exocrine glands (has ducts)

Secretes products through ducts that lead to a specific location

Two types of Exocrine gland secretions

Merocrine Secretion and Holocrine secretion

Merocrine secretion

When a cell releases its product into a vesicle that allows it to travel

Holocrine secretion

When a gland bursts to release the product from inside of it

Example of Merocrine secretion

When sweat is produced

Example of Holocrine secretion

Cells itself detaches and releasing sebum into the duct

Proper Connective Tissue

Loose Dense Reticular Adipose

Specialized connective tissue

Cartilage Bone and Blood

Connective Tissue function

Connect, Bind, Support, Protect, and Transport

Characteristics of CT

Cells surrounded by protein fibers and embedded in ground substance

What does blast mean

To build

Connective Tissue Cells

Fibroblasts Adipocytes Mast Cells and Phagocytes

Fibroblasts

Form and maintain connective tissue, create ECM

Adipocytes

Cells that store fat

Mast Cells

produce histamine

Phagocytes

Eats and absorbs bacteria 

where is loose connective tissue

Located under epithelial tissue and in membranes lining body cavities

Where is dense irregular tissue

Found in the dermis of the skin

Where is dense regular tissue

Found in tendons

Where is reticular connective tissue found 

Found in lymphoid organs

Where is cartilage found

in the ears and nose

Where is bone tissue found

throughout the entire skeleton

Where is blood found

In veins that circulate the entire body

What are two functions of the loose CT

Binds structures and allows for diffusion of water and nutrients

What are two functions of dense irregular CT

Provides strength and resistance to tearing from stretching

What are 2 main functions of dense regular CT

Connects muscles to bones and provides resistance to pulling

What are two functions of reticular CT

Provides structural support Holds and supports immune cells

What are two functions of cartilage

Shock absorption and Flexibility

What’s the two functions of the blood tissue

Transports oxygen and carries away waste

functions of bone tissue

Provides structural support

What are the 3 types of cartilage

Hyaline, Fibrocartilage, elastic

Hyaline cartilage

Provides smooth low friction surfaces

Fibrocartilage

Strongest tissue, avascular

Elastic cartilage

Flexible

What are the 3 types of muscle tissue

Skeletal muscle Cardiac muscle and Smooth muscle

Skeletal muscle

Attached to bone, Voluntary movement

Cardiac Muscle

Heart muscle, involuntary movement

Smooth muscle

In digestive system, involuntary movement

Nervous tissue

Doesn’t repair made of Neurons and Neurological cells

Synovial membranes

Made up of CT and lines joints

Cutaneous

Skin

Regeneration

Dead tissue replaced with the same type of tissue

Fibrosis

Replace dead tissue with scar tissue