BSC2085 Exam 2

Three Characteristics of Connective Tissue

Specialized cells, solid extracellular protein fibers, fluid extracellular ground substance

Properties of Ground Substance

Fill space between cells, slow pathogen movement

What makes up the matrix of connective tissue?

The Extracellular Components (fibers and ground substance)

What is the function of the matrix?

the matrix makes up the majority of the connective tissue volume and determines specialized function

Functions of Connective Tissue

1. Establishing a structural framework for the body

2. Transporting Fluids and dissolved materials

3. Supporting, surrounding, and interconnecting other tissues

4. Storing energy reserves - triglycerides

5. Defending the body from invading microorganisms`

Three Categories of Connective Tissues

1. Connective Tissue Proper

2. Fluid Connective Tissue

3. Supporting Connective Tissue

Connective Tissue Proper

Functions to connect and to protect (tendons and adipose tissue)

Fluid Connective Tissue

Functions in transportation (blood and lymph)

Supporting Connective Tissue

Provides structural strength (cartilage and bone)

Nine Connective Tissue Proper Cell Populations

1. Fibroblasts

2. Fibrocytes

3. Adipocytes

4. Mesenchymal Cells

5. Macrophages

6. Mast Cells

7. Lymphocytes

8. Microphages

9. Melanocytes

Fibroblasts

1. Most abundant

2. Found in ALL connective tissue proper

3. secrete proteins and hyaluronan (cellular cement)

Fibrocytes

1. Second most abundant - develops from fibroblasts

2. Fount in ALL connective tissue proper

3. Maintain the fibers of connective tissue proper

Adipocytes

1. Fat Cells

2. Each stores a single fat droplet

3. Functions as energy reserve and cushions tissues/organs

Mesenchymal Cells

1. Found in many connective tissues

2. Stem Cells (differentiate to different cells in response to injury or infection)

Macrophages

1. Large cells of the immune system

2. Eat pathogens

3. Two Classes of Macrophages

Two classes of Macrophages

1. Fixed Macrophages

2. Free Macrophages

Fixed Macrophages

Stay in tissue, act as frontline defense, reinforced by free macrophages and other cells

Free Macrophages

Migrate through the tissue

Mast Cells

1. Stimulate inflammation after injury or infection

2. Release histamine to stimulate local inflammation and heparin to prevent blood clots

Lymphocytes

1. Specialized immune cells in lymphatic system

2. Lymphocytes may develop into plasma cells (plasmocytes) that produce antibodies

Two types of Microphages

Neutrophils and Eosinophils

Microphages

1. Phagocytic white blood cells

2. move through the connective tissue in small numbers

3. Respond to signals from Macrophages and Mast Cells

Melanocytes

1. Synthesize and store the brown pigment Melanin

2. Located in the eye and in the dermis of the skin

Mesenchyme is also known as?

Embryonic Connective Tissue

Mesenchyme

1. The first connective tissue in embryos

2. Gives rise to all other connective tissues

3. Are not found in adults

Mucous connective tissue is also known as?

Wharton's Jelly

Mucous Connective Tissue

1. Loose connective tissue found in many parts of embryo, including umbilical cord

2. Not found in adults

Adipose Tissue

1. Contains adipocytes

2. Incapable of dividing in adults

3. Shrinks does not die

Two Types of Adipose Tissue

1. White Fat

2. Brown Fat

White Fat

1. Most common

2. Stores Fat

3. Absorbs Shocks

4. Acts as insulation

Brown Fat

1. More Vascularized - widespread in fetus and infants

2. Adipocytes have many mitochondria

3. When stimulated, fat breakdown accelerates, releasing energy as heat

What is Fluid Connective Tissue made of

A watery mix of dissolved proteins

What is the function of Fluid Connective Tissue

1. Carry specific cell types (formed elements)

What are the formed elements in the blood?

1. Red Blood Cells (erythrocytes)

2. White Blood Cells (leukocytes)

3. Platelets

Extracellular fluid elements of connective tissue

1. Plasma

2. Interstitial Fluid

3. Lymph

Lymph

1. Extracellular fluid collected from interstitial space

2. Monitored by immune system

3. Transported by lymphatic system

4. Returned to venous system

Cartilage

1. Gel-Type ground substance

2. For shock absorption and protection

Bone

1. Calcified (made of calcium)

2. For weight support

What produces Cartilage?

Chondrocytes

Properties of Cartilage

Avascular

What do Chondrocytes do?

Produce Antiangiogenesis factor which prevents the formation of new blood vessels

What makes up bone tissue?

Osteocytes

Properties of Bone

1. Strong

2. Resists shattering (flexible collagen fibers imbedded)

What are Membrane?

physical barriers that line or cover portions of the body

What do membranes consist of?

an epithelium supported by connective tissue

Four types of membranes

1. Mucous

2. Serous

3. Cutaneous

4. Synovial

Mucous Membrane

1. Line passageways that have external connections

2. Epithelial cur faces must be moist

Location of Mucous Membranes

1. Digestive

2. Respiratory

3. Urinary

4. Reproductive

Serous Membrane is composed of?

Mesothelium and areolar tissue

Serous Membrane

1. Lines cavities not open to the outside

2. Thin but strong

3. Have fluid transudate (fluid) to reduce friction

4. Two layers

Two layers of the serous membrane?

1. Parietal (covering the cavity)

2. Visceral (covering the organs)

Three Serous Membranes

1. Pleura

2. Peritoneum

3. Pericardium

Pleura

1. lines pleural cavities (parietal)

2. covers lungs (visceral)

Peritoneum

1. Lines peritoneal cavity (parietal)

2. covers abdominal organs (visceral)

Pericardium

1. Lines pericardial cavity (parietal)

2. Covers heart (visceral)

Cutaneous Membrane

Is skin, on body surface. Is thick, waterproof, and dry

Synovial Membranes

1. Line moving joint cavities

2. Protect ends of bone

3. Lack true epithelium

Synoviocytes

Line the cavity and produce synovial fluid (lubricant)

Three Functions of Connective Tissues

1. Provide Strength and Stability

2. Maintain positions of internal organs

3. Provide routes for blood and lymphatic vessels and nerves

Fasciae

The body's framework of connective tissues that wraps and supports organs

Three types of Fasciae

1. Superficial

2. Deep

3. Subserous

Superficial Fascia

1. AKA hypodermis - insulation and padding

Deep Fascia

Resists multidirectional forces; bound to capsules around most organs, tendons, and ligaments

Subserous Fascia

protects body cavity lining when muscles/muscular organs move

Muscle tissue is specialized to?

Contract

Functions of muscle tissue

1. produce all body movement

Three types of muscle tissue

1. skeletal

2. cardiac

3. smooth

Skeletal muscle tissue

large body muscles responsible for body movement

Cardiac Muscle Tissue

found only in the heart

Smooth muscle tissue

found in walls of hollow, contracting organs (urinary bladder etc)

Classification of Muscle Cells

1. Striated (banded)

2. Nonstriated (smooth)

3. can have a single nucleus or be multinucleated

4. controlled voluntarily/involuntarily

skeletal muscle cells are also called

muscle fibers

Properties of skeletal muscle cells

1. voluntary control

2. long and thin

3. striated and multinucleated

4. do not divide

5. low repair ability

Myosatellite

Stem Cells

Cardiac Muscle Cells are also known as

Cardiocytes

Properties of cardiac muscle cells

1. involuntary control

2. striated, single nucleus

3. form branching networks connected at intercalated discs

4. regulated by pacemaker cells

Intercalated discs

Gap junctions that connect one cell to another

Properties of Smooth Muscle Cells

1. Non striated, single nucleus

2. involuntary control

3. small and tapered

4. can divide and regenerate

Neural Tissue

1. conducts electrical impulses

2. senses environment

3. processes information and controls responses

4. concentrated in the CNS

Two Types of Neural Cells

Neurons and Neuroglia

Neurons

nerve cells, perform electrical communication

Neuroglia

supporting cells, repair and supply nutrients to neurons

The Integument

1. The largest system of the body

2. 16% of body weight

3. 1.5 to 2 meters in area

Two parts of the integument

1. Cutaneous membrane (skin)

2. Accessory Structures

Two parts of the cutaneous membrane

1. Outer Dermis

2. Inner Dermis

Outer dermis makes up the

superficial epithelium (epithelial tissues)

The Inner dermis makes up

connective tissues

Accessory Structures

1. Originate in the dermis

2. Extended through the epidermis to skin surface

Accessory structures include:

1. Hair

2. Nails

3. Multicellular exocrine glands

The integumentary system is connected to...

1. Cardiovascular System

2. Nervous System

How is the integumentary system connected to the cardiovascular system?

By blood vessels in the dermis

How is the integumentary system connected to the nervous system?

By sensory receptors that detect stimuli for pain, touch, and temperature

Hypodermis is also known as

Superficial Fasia or subcutaneous layer

Is the hypodermic considered part of the integumentary system?

No

Properties of the hypodermis

1. Located below the dermis

2. composed of loose connective tissue - separates integument from the deep fascia around organs

3. location of hypodermic injections

Five main functions of the skin

1. Protection of tissues and organs

2. Excretion of salts, water, etc

3. Maintenance of body temp

4. Production of melanin, keratin etc.

5. Detection of touch, pain, pressure, temperature

The Epidermis is made up of what type of epithelium?

Avascular stratified squamous epithelium

The Epidermis is dominated by what type of epithelial cell?

Keratinocytes - contain large amounts of protein keratin

Properties of thin skin

1. covers most of the body

2. has four layers of keratinocytes

Properties of thick skin

1. covers the palms of the hands and soles of the feet

2. has FIVE layers of keratinocytes