Tissues part II September 11 2018 Connective Tissues

Tissues part II September 11, 2018

Connective Tissues �Most abundant tissue type! �Functions: � Protection � Support � Binding together

Connective Tissues �All connective tissues are made up of cells and extracellular matrix. �The extracellular matrix is secreted by the cells. �The extracellular matrix is composed of � Ground substance (water, adhesion proteins (‘glue’), polysaccharide molecules). The ground substance can be fluid or firm depending on how many polysaccharides there are. � Fibers – the types and amounts vary. �Collagen – strongest �Elastic – stretchable �Reticular – netlike & supportive

Connective Tissues Turn and talk … How does the extracellular matrix help connective tissue due its jobs? … 2 min

Connective Tissues Bone (osseous tissue) � Hardest connective tissue � Osteocytes (bone cells) found in lacunae � Functions: support, protection, movement � Contain collagen fibers calcium salts

Connective Tissues Cartilage � Softer & more flexible than bone � Chondrocytes (cartilage cells) found in lacunae � 3 types of cartilage, each containing different proportions of the 3 fibers �Hyalin: ends of bones �Fibrocartilage: vertebrae �Elastic: external ear

Dense Connective Tissue � Forms tendons, ligaments, and layer beneath skin � Fibroblasts (fiber-forming cells) between collagen fibers Dense irregular – dermis (below skin) submucosa of digestive tract Dense regular – tendons, ligaments

Loose Connective Tissues Areolar Tissue (areola = small open space) � Most common connective tissue! � Cushions, packages, and holds organs in place � Consists of fibers and cells (fibroblasts and immune cells) scattered loosely in a fluid containing water, nutrients, salts and waste This is one of the tissues that swells most when damaged. Swelling = edema

Loose Connective Tissues Adipose Tissue (fat!) � Very little matrix, mostly adipocytes � Each cell filled with oil � Functions: fuel reserve, insulation, cushion organs What do you call stored nutrients (like fat) within a cell?

Loose Connective Tissues Adipose Tissue (fat!) � Very little matrix, mostly adipocytes � Each cell filled with oil � Functions: fuel reserve, insulation, cushion organs What do you call stored nutrients (like fat) within a cell? inclusions

Loose Connective Tissues Adipose Tissue (fat!) � Very little matrix, mostly adipocytes � Each cell filled with oil � Funcitons: fuel reserve, insulation, cushion organs Just for fun … What is a healthy % body fat?

Loose Connective Tissues Adipose Tissue (fat!) � Very little matrix, mostly adipocytes � Each cell filled with oil � Functions: fuel reserve, insulation, cushion organs Just for fun … What is a healthy % body fat? Adult women: 21%-33% Adult men: 8% - 19%

Loose Connective Tissues Adipose Tissue (fat!) � Very little matrix, mostly adipocytes � Each cell filled with oil � Functions: fuel reserve, insulation, cushion organs What happens to your fat cells when you lose weight?

Loose Connective Tissues Adipose Tissue (fat!) � Very little matrix, mostly adipocytes � Each cell filled with oil � Functions: fuel reserve, insulation, cushion organs What happens to your fat cells when you lose weight? They shrink, but never go away. This is one reason why it is so easy to regain weight that you have lost.

Blood • Consists of cells within a matrix – plasma. • Like other connective tissues, blood does have fibers, but these are only involved in clotting. • Function: transport nutrients, waste, heat throughout the body We will cover in much more detail later!

Connective Tissue Review What characteristics do all connective tissues have, and how does this help them do their functions? 2) Notice any patterns in the naming of cells? 3) Rank the connective tissues in terms of rigidity. 1) Work with a partner. 5 min. Be prepared to share with class.

Muscular Tissue Function: Contraction for movement Special Features: 1. Possess myofilaments (actin & myosin) which slide past each other to contract the cell 2. Well vascularized (many blood vessels) to supply energy and oxygen

Muscular Tissue Skeletal muscle �Voluntary muscles of the body �Skeletal b/c attached to bones (mostly) �Long, cylindrical, striated (banded) cells with multiple nuclei � Skeletal muscle cells are called muscle fibers

Muscular Tissue Skeletal muscle �Voluntary muscles of the body �Skeletal b/c attached to bones (mostly) �Long, cylindrical, striated (banded) cells with multiple nuclei � Skeletal muscle cells are called muscle fibers Structure & Function – Long, parallel cells – allow contraction in one direction to pull a bone.

Muscular Tissue Cardiac muscle �Found in heart �Striated, but branching (have to squeeze) �Contain intercalated discs – allow for rapid spread of electrical impulse for coordinated contraction

Muscular Tissue Smooth muscle �Found in walls of hollow organs (digestive, bladder, uterus, blood vessels) �Slowly squeezes and relaxes (in all directions) to propel substances through �Motion called peristalsis

Muscular Tissue Smooth muscle �Found in walls of hollow organs (digestive, bladder, uterus, blood vessels) �Slowly squeezes and relaxes (in all directions) to propel substances through �Motion called peristalsis Structure & Function – notice that it is less organized than the others – because squeezing occurs in all directions

Nervous Tissue �Function: to convey electrochemical impulses from one structure to another �Consists of neurons and support cells (that insulate, support and protect neurons) �Neurons have long processes to carry impulse to distant areas.

Quick Review – Identify tissue type Show the correct answer with your fingers 1. 2. 3. 4. 5. Dense connective Areolar Smooth muscle Cartilage Adipose

Quick Review – Identify tissue type Show the correct answer with your fingers 1. 2. 3. 4. 5. Dense connective Areolar Smooth muscle Cartilage Adipose

Quick Review – Identify tissue type Show the correct answer with your fingers 1. 2. 3. 4. 5. Dense connective Areolar Smooth muscle Cartilage Adipose

Quick Review – Identify tissue type Show the correct answer with your fingers 1. 2. 3. 4. 5. Dense connective Areolar Smooth muscle Cartilage Adipose Dense connective has much less nuclei (much less cells / more fibers) than smooth muscle

Quick Review – Identify tissue type Show the correct answer with your fingers 1. 2. 3. 4. 5. Blood Bone Nervous Cartilage Adipose

Quick Review – Identify tissue type Show the correct answer with your fingers 1. 2. 3. 4. 5. Blood Bone Nervous Cartilage Adipose Matrix is smooth & so dense you can’t see fibers. Chondrocytes in lacunae.

Quick Review – Identify tissue type Show the correct answer with your fingers 1. 2. 3. 4. 5. Blood Bone Nervous Cartilage Adipose

Quick Review – Identify tissue type Show the correct answer with your fingers 1. 2. 3. 4. 5. Blood Bone Nervous Cartilage Adipose Looks like empty circles – actually cells filled with fat

Quick Review – Identify tissue type Show the correct answer with your fingers 1. 2. 3. 4. 5. Smooth muscle Cardiac muscle Skeletal muscle Nervous Bone

Quick Review – Identify tissue type Show the correct answer with your fingers 1. 2. 3. 4. 5. Smooth muscle Cardiac muscle Skeletal muscle Nervous Bone Long, branching cells and intercalated discs

Quick Review – Identify tissue type Show the correct answer with your fingers 1. 2. 3. 4. 5. Smooth muscle Nervous Skeletal muscle Blood Bone

Quick Review – Identify tissue type Show the correct answer with your fingers 1. 2. 3. 4. 5. Smooth muscle Nervous Skeletal muscle Blood Bone Notice the long processes and supporting cells.