a and p mod#2 pages 42-50

Pages 42 – 50

Exocrine glands come in many arrangements/types:

Glandular EpitheliumThere are two types of glands:

1. Exocrine glands

Types of exocrine glands based on how they secrete:

a. Merocrine glands – by exocytosis (without losing cellular material) into the duct.

Example sweat glands.

Merocrine gland directly secretes into duct.

http://www.med.umich.edu/histology/fieldTrip/sweatGland.jpg

Glandular EpitheliumThere are two types of glands:

1. Exocrine glands

Types of exocrine glands based on how they secrete: a. Merocrine glands

b. Apocrine glands - a portion of the plasma membrane containing the secretion and some cytoplasm buds off the cell and enters the duct.

Ex. Mammary glands

Apocrine Gland

There are two types of glands:

1. Exocrine glands

Types of exocrine glands based on how they secrete: a. Merocrine glands

b. Apocrine glands

c.holocrine gland - the entire cell containing its secretion

disintegrates in the duct.

Ex. Oil glands

Glandular EpitheliumThere are two types of glands:

1. Exocrine glands

2. Endocrine gland no ducts secrete hormones by exocytosis intointerstitial fluids that surround cellsand blood stream picks them up.Ex. Thyroid gland

Endocrine Glands

Type Function LocationSimple Squamous Diffusion Blood vessels, lungsSimple Cuboidal Diffusion and secretion Kidneys

Simple Columnar Mucous producing Stomach and intestines

Stratified Squamous Protection, secreting Skin, lining mouth

Stratified Cuboidal Protection, secreting Protect Salivary glands - rare

Stratified Columnar Protection, secreting Pharynx, larynx, uterus - rare

Stratified Transitional Stretches, changes shape Urinary bladder

Epithelial Tissue – Functions and locationsHandout

Why does skin flake off? Cells at top of skin are so far from nutrients that they are dead.

Keratin – protein that fills dead epidermal cells at top layer

Keratinized membrane – top layer of skin cells that are dead and filled with keratin.

Where quiz stops

CONNECTIVE TISSUE

FUNCTION: insulate, support and bind (infrastructure)

CONNECTIVE TISSUE continued

CHARACTERISTICS:

Greater space between cells (extracellular space) compared to epithelial tissue

cells secrete extracellular material or MATRIX which fills space between cells

CONNECTIVE TISSUE continued

CHARACTERISTICS:

Matrix is the material between the cell which contains ground substance (non-collagenous part of matrix) and collagen protein fibers.

CONNECTIVE TISSUE continued

CHARACTERISTICS:

Connective Tissue is classified according to the type of extracellular matrix it produces

CONNECTIVE TISSUE

TYPES:1. connective tissue proper2. cartilage3. bone4. blood

TYPE 1: Connective Tissue Proper

Guess how many kinds of connective tissue proper

there are?

4

TYPE 1: Connective Tissue Proper

Four types of Connective Tissue Proper:

A. Loose connective tissueExtracellular matrix is not strong

Is used for light binding and flexibility

Also called areolar connective tissue

TYPE 1: Connective Tissue Proper

Four types of Connective Tissue Proper:

A. Loose connective tissue

Found between the skin and the muscles holding the skin to musclesHas fibroblasts which make tissue’s ground substance, protein fibers, collagen fibers Mature fibroblast are called fibrocytes

Loose Connective Tissue Proper

fibroblast

Four types of Connective Tissue Proper:A. Loose connective tissue

B.Dense irregular connective tissue

Part of the skin

Collagen fibers more densely packed than loose connective tissue

B. dense irregular connective tissue continued

Denser packing give tissue more strength

Irregular because fibers run every which way

Dense irregular connective tissue proper

Four types of Connective Tissue Proper:A. Loose connective tissueB. Dense irregular connective tissue

C. Dense regular connective tissue properCollagen fibers run in one

direction giving more strength called tensile strength

Found in tendons which hold muscle to bones and ligaments that hold bone to bone

c. Dense regular connective tissue proper

Tendons and ligaments take a long time to heal when injured because of dense amount of extracellular material (fibers, etc.) that they must manufacture.

Dense regular connective tissue proper

Four types of Connective Tissue Proper:A. Loose connective tissueB. Dense irregular connective tissueC. Dense regular connective tissue proper

D. Adipose tissue

Fatty tissue

it has fat cells in it as well as connective tissue cells

D. Adipose tissue

Function is to store energy, insulate, and to hold organs in place

Example – kidneys are protected and held in place by adipose tissue