Muscle and the functions of glands 9/29

• What are the primary characteristics of the three types of muscle tissue?

• What cell adhere to/connect with each other and the basement membrane?

• How are glands classified?• What are the primary secretions?• What is the mucus membrane?

Practice Quiz for Yesterday’s Notes1) What cell type produces the extracellular protein collagen?

Endothelium Fibroblast Leukocyte Erythrocyte2) Negative charges and a loose fitting amino acid sequence allow what

type of connective tissue fibers to stretch? Elastin

3) True/False: The ectodermal germ layer is the embryonic source of the connective tissue we call blood.

4) Which of the three different kinds of “Loose Connective Tissues” would you find in the spleen or lymph nodes?Areolar Adipose Reticular Simple Squamous Blood

5) Pseudostratified Columnar Epithelial Tissues would be found lining what organ?Esophogus---Capillary---Lung Alveoli---Trachea---Finger Callus

6) What kind of tissue(s) are between the air in an alveolus of the lung and the blood?

7) What kind of cells and how many cells does O2 pass through before entering the blood from an alveoli? 1 cell 2 cells 3 cells 4 cells

Dense Regular Connective Tissue: Note that fibroblasts (blue nuclei) are squeezed between the fibers.

Muscle has the ability to shorted because of actin and myosin filaments that are inside the cells.

What are the three types of muscle tissue? • All three types have actin and myosin, two proteins that

facilitate a change in cell length (contraction)

• Skeletal Muscle Tissue: Voluntary control, striated appearance, multinucleate, and a short period of contraction (many mitochondria)

• Cardiac Muscle Tissue: Involuntary control, striated appearance, one nucleus/cell, and a short period of contraction (many mitochondria)

• Smooth Muscle Tissue: Involuntary control, no striations, one nucleus/cell and long sustained contractions (few mitochondria)

Smooth muscle provides contractions that are long-term and exerted on many different planes/angles of force.• Muscle Fiber Shape/Size:• Actin/myosin not parallel

– No Striations!• Gap Junction “possible”• Orientation as Sheets/Tubes:

• Axon synapse is optional for depolarization

• Often times on exams students will confuse this tissue with Regular Dense Connective Tissue which can look very similar.

Skeletal muscle tissues provide for movement of the entire body!

• Muscle Fiber: multiple nuclei/fiber on outside but still within the plasma membrane!

• Striations from actin and myosin• Parallel orientation:

Axonal synapse required for depolarization!DepolarizationContraction (short duration)• Numbers of fibers recruited is variable

• Anabolic muscle growth in Hulk Hogan:

• Muscle Size: “It’s the size not the numbers!”

Cardiac tissues provide a heart that beats as a “syncitial” unit!

• Fibers: single nuclei/cardiac myocyte:• Striations: actin, myosin• Intercalated discs for cellular adherence• Gap Junctions for electric syncitium

• Cells can spontaneously depolarize!• Axon synapse NOT required for depolarization• DepolarizationContraction

• Numbers of fibers recruited is NOT variable

• A Strong Heart: “It’s the size not the numbers!”

4 main types of cell-cell connection: Tight Junction: prevent chemical diffusion and infection Desmosome: attach neighboring cellsHemidesmosome: attach cells to basement membraneGap Junction: is a pore (hole) between cells

For hooking cells together, preventing water loss, and providing direct communication between cells here are three main connection types to choose from: 1)Gap Junction---2)Tight Junction---3)Desmosome

Secretion classification is based on fluid destination: Exocrine or Endocrine

• Unicellular glands of PSCE and Simple Columnar: The Goblet Cell Mucus to moisten/lubricate/protect

• Secretions: Physiological vs. Excretion: Waste (Urine)• Exocrine Glands: Secretion to exit body via Ducts!

– Line glands with simple (OR STRATIFIED) cuboidal epithelial tissue

– Serous glands-– Mucous glands-

• Endocrine Glands: Secretions stay inside body: No Ducts!– Local or distant targets– Blood may be needed to carry secretion to targetThyroid Gland Hormone called Thyroxine Metabolic rateAnterior Pituitary Growth Hormone Self ExplanatoryAdrenal Gland (Medulla Epinephrine (adrenalin) Adrenal Gland (Cortex) CorticolAdrenal Gland Stress Management

Exocrine Gland means “Exit” body: Via DuctEndocrine Gland mean “Into” body: No DuctsPancreas has BOTH types of function!

What types of exocrine glands exist?Why bury the glands deep in the dermis?

Which glands are found where?• Lobular

Structure:

Location/Shape:• Sweat-• Gastric Pits-• Kidney-• Mammary-• Pancreatic-• Urethra-

How does the mucus membrane work?Mucus: Function, Composition, Location

Muc.Membr=Epithelium + lamina

prop.

What is mucus?????What does it do????

ID These Items:PseudostratifiedCE:Goblet Cell:Cilia:Basement Membrane:Areolar Tissue (lamina

propria):SMC Functions in

muscularis mucosae: