Tissues: The living fabric Ch 4 b Connective Tissue

Let’s review Epithelial tissue First Let’s review Epithelial tissue

What type is this?

Simple cuboidal epithelium

What type is this?

Simple cuboidal epithelium

What type is this?

Transitional epithelium

What type is this?

Transitional epithelium

What type is this?

Pseudostratified epithelium

Pseudostratified epithelium What is this called?

Pseudostratified epithelium What is this called? Cilia!

What type is this?

Stratified squamous epithelium

What tissue is this?

What type is this?

Simple columnar epithelial tissue

Connective Tissue

Connective Tissue Found throughout the body Most abundant and most widely distributed

Connective Tissue Four Main classes Connective tissue proper Includes fat and fibrous tissue of ligaments Cartilage Bone Blood

Functions of Connective Tissue Binding and support Protection Insulation Transportation blood

Characteristics of Connective Tissue Connective tissues have: Common origin Arise from Mesenchyme (an embryonic tissue) Varying degrees of vascularity From avascular to rich in blood vessels

Characteristics of Connective Tissue Has large amounts of nonliving extracellular matrix, consisting of ground substance and fibers

Structural Elements of Connective Tissue Has 3 main elements: 1. Ground substance – unstructured material that fills the space between cells 2. Fibers – collagen, elastic, or reticular

Structural Elements of Connective Tissue Has 3 main elements: 3. Cells – fibroblasts, chondroblasts, osteoblasts, and hematopoietic stem cells

Structural Elements of Connective Tissue Ground substance and fibers make up the matrix

Ground Substance Functions as a molecular sieve through which nutrients diffuse between blood capillaries and cells Proteoglycan Structure

Ground Substance Composed of: Interstitial (tissue) fluid Adhesion proteins– serves as the glue Proteoglycans – (protein core with glycosaminoglycans (GAGs) attached Traps water

Fibers – 3 types Collagen – Strongest, most abundant; tough and provides high tensile strength (stronger than steel fibers the same size) Glistening white appearance – called white fibers

Fibers Elastic – long, thin fibers form branching network allows for stretch Contains rubber-like protein called elastin Appear yellow so sometimes called yellow fibers

Fibers Reticular – branched collagenous fibers form delicate networks Abundant where connective tissue abuts other tissue types Basement membrane of epithelial Form nets around capillaries

Cells Immature and Mature forms Actively mitotic immature cells that secrete ground substance and fibers in their particular matrix

Cells Immature and Mature forms Fibroblasts – connective tissue proper Chondroblasts – cartilage Osteoblasts – bone Hematopoietic stem cells – blood

Cells Once matrix is synthesized, the blast cells mature into less active cells (indicated by the suffix –cyte) Hematopoietic stem cells are always actively mitotic Other cell types in connective tissue include White blood cells, plasma cells, macrophages, and mast cells

Types of Connective Tissue

Connective Tissue: Embryonic Mesenchyme – embryonic connective tissue Gel-like ground substance with fibers and star-shaped mesenchymal cells Gives rise to all other connective tissues Found in the embryo

Connective Tissue: Embryonic Figure 4.8a

Connective Tissue Proper 2 subclasses Loose connective tissue Areolar, adipose, and reticular Dense connective tissue Dense regular, dense irregular, and elastic

Connective Tissue Proper: Loose Areolar connective tissue Gel-like matrix with all three connective tissue fibers Fibroblasts, macrophages, mast cells, and some white blood cells Wraps and cushions organs Widely distributed throughout the body

Areolar Connective Tissue Figure 4.8b

Connective Tissue Proper: Loose Adipose connective tissue Matrix similar to areolar connective tissue with closely packed adipocytes (fat cells) Reserves food stores, insulates against heat loss, and supports and protects

Connective Tissue Proper: Loose Adipose connective tissue Found under skin, around kidneys, within abdomen, and in breasts Local fat deposits serve nutrient needs of highly active organs

Connective Tissue Proper: Loose Adipose connective tissue Abundant – average person 18% of body weight is adipose Chubby person body can be 50% adipose tissue

Adipose Figure 4.8c

Connective Tissue Proper: Loose Reticular connective tissue Loose ground substance with reticular fibers Reticular cells that lie in a fiber network Forms a soft internal skeleton, or stroma, that supports other cell types

Connective Tissue Proper: Loose Reticular connective tissue Found in lymph nodes, bone marrow, and the spleen

Reticular Connective Tissue Figure 4.8d

Connective Tissue Proper: Dense Regular Parallel collagen fibers with a few elastic fibers Major cell type is fibroblasts Attaches muscles to bone or to other muscles, and bone to bone Found in tendons, ligaments, and aponeuroses

Dense Regular Connective tissue Figure 4.8e

Connective Tissue Proper: Dense Irregular Irregularly arranged collagen fibers with some elastic fibers Major cell type is fibroblasts Withstands tension in many directions providing structural strength

Connective Tissue Proper: Dense Irregular Found in the dermis, submucosa of the digestive tract, and fibrous organ capsules

Dense Irregular Figure 4.8f

Cartilage Stands up to tension and compression Tough but flexible Lacks nerve fibers Avascular Cartilage matrix is up to 80% water Heals very slowly

Cartilage 3 types – hyaline elastic fibrocartilage

Connective Tissue: Hyaline Cartilage Most abundant Glassy blue white appearance Supports, reinforces, cushions, and resists compression Forms the costal cartilage Found in embryonic skeleton, the end of long bones, nose, trachea, and larynx

Connective Tissue: Hyaline Cartilage Figure 4.8g

Connective Tissue: Elastic Cartilage Similar to hyaline cartilage but with more elastic fibers Maintains shape and structure while allowing flexibility Supports external ear (pinna) and the epiglottis

Connective Tissue: Elastic Cartilage Similar to hyaline cartilage but with more elastic fibers Maintains shape and structure while allowing flexibility Supports external ear (pinna) and the epiglottis Figure 4.8h

Connective Tissue: Fibrocartilage Cartilage Matrix similar to hyaline cartilage but less firm with thick collagen fibers Provides tensile strength and absorbs compression shock Found in intervertebral discs, the pubic symphysis, and in discs of the knee joint

Fibrocartilage Cartilage Matrix similar to hyaline cartilage but less firm with thick collagen fibers Provides tensile strength and absorbs compression shock Found in intervertebral discs, the pubic symphysis, and in discs of the knee joint Figure 4.8i

Connective Tissue: Bone (Osseous Tissue) Hard, calcified matrix with collagen fibers found in bone Osteocytes are found in lacunae and are well vascularized Supports, protects, and provides levers for muscular action

Connective Tissue: Bone (Osseous Tissue) Stores calcium, minerals, and fat Marrow inside bones is the site of hematopoiesis (blood formation)

Bone (Osseous Tissue) Figure 4.8j

Connective Tissue: Blood Red and white cells in a fluid matrix (plasma) Contained within blood vessels Functions in the transport of respiratory gases, nutrients, and wastes

Connective Tissue: Blood Figure 4.8k

What kind is this?

Areolar Connective Tissue

What kind is this?

Areolar

What kind is this?

Reticular Connective tissue

What kind is this?

Reticular connective tissue

What kind is this?

Reticular connective tissue

What kind is this?

Bone or Osseous tissue

What kind is this?

Bone (osseous) tissue

What kind is this?

Elastic Cartilage

What kind is this?

Fibrocartilage

What kind is this?

Hyaline Cartilage

What kind is this?

Adipose (fat)

What kind is this?

Adipose (fat)

What kind is this?

Adipose (fat)

What kind is this?                                               blood

Blood                                               blood

What kind is this?

Blood

What kind is this?

Blood

What kind is this?

Dense Regular connective

What kind is this?

Dense Regular connective

What kind is this?

Dense Irregular connective

I will be checking study guides pages 8-16 Quiz – Next time! I will be checking study guides pages 8-16