Animal Structure and Muscle Function “Success is going from failure to failure without losing your enthusiasm.” -Winston Churchill “The cure for boredom is curiosity. There is no cure for curiosity.” -Ellen Parr Animal Structure and Muscle Function Chapters 40-49

Animal Tissues Tissues: groups of cells with similar structure that perform a common function Types of Animal Tissue: Epithelial Tissue Tightly packed cells used for _______ Connective Tissue Cells scattered through an __________________ Nervous Tissue _________________(neurons) Muscle Tissue Fibers for _______________

Epithelial Tissue Covers outside of body and line _______ __________ within the body Barrier Polarized cells Apical surface faces lumen (cavity)

Epithelial Tissue Cell layers Shape of Cells Simple Stratified Pseudostratified Shape of Cells Cuboidal Columnar Squamous Cubodial: cube shaped Columar: column shaped Squamous: scale like in appearance, Flat, spread out.

Simple Squamous Lines blood vessels and air sacs in lungs Permeable Areas of filtration and diffusion of molecules Lab Photo Simple – one layer thick Squamous – scale like, flat

Simple Cuboidal Line the thyroid, salivary glands, nephrons, ovaries Specialized for ____________ Lab Photo Simple: one layer thick Cubodial: cube shaped

Simple Columnar Lines most organs in the digestive tract Stomach and intestines Important for secretion Lab Photo

Pseudostratified Columnar Ciliated cells form mucus membrane that line ______________ Lab Photo

Stratified Squamous ___________ tissue with cells that regenerate quickly Outer skin, and linings of mouth, anus, vagina

Connective Tissue ___________: cells that secrete fiber proteins Fibers that make up Connective Tissue: Collagenous Fibers Strength and flexibility Collagen Elastic Fibers Elasticity Elastin Reticular Fibers Join connective tissue to adjacent tissue

Types of Connective Tissue

Loose Connective Tissue Binds epithelia to underlying tissue and holds _______ in place Surrounds blood vessels and nerves Lab Photo Elastic fibers Collagenous fibers Made up of collagenous fibers (support), elastic fibers (stretch) and reticular fibers (join tissues) Fibroblasts

Fibrous Connective Tissue Dense tissue made up of collagenous fibers used to attach _____________ (tendons) and bones to joints (ligaments) Lab Photo Collagen fibers Fibroblasts

Bone Mineralized connective tissue Osteoblasts: bone-forming cells Osteon Central canal Lab Photo Osteon Central canal Osteoblasts

Cartilage Strong, but flexible tissue that functions in support __________________: cartilage forming cells Lab Photo Chondrocytes

Adipose Tissue ____________: cells containing fat droplets that protect and insulate the body while storing energy reserves Lab Photo Fat droplets

Blood Plasma: liquid, extracellular matrix ______________ (red blood cells) Oxygen transport ___________ (white blood cells) Immune response Platelets Clotting Platelets Leukocytes Erythrocytes

Nervous Tissue Receive, process, and transmit information Neurons (nerve cells) Dendrites Cell body Axon Glia: support and protect nerve cells Dendrites Cell Body Axon

Muscular Tissue Responsible for body movement Types of Muscular Tissue: Skeletal muscle Smooth muscle Cardiac muscle

Smooth Muscle Involuntary (autonomous) control Digestive tract, bladder, blood vessels Lacks sarcomeres Lab Photo Muscle fibers Nuclei

Cardiac Muscle Contractile wall of heart Involuntary Striated Intercalated disks Synchronize contraction Lab Photo Nuclei Intercalated disks

Skeletal Muscle Responsible for voluntary movement Myocytes: _______________ muscle fibers Sarcomeres Lab Photo Nuclei Muscle fiber Sarcomere

Vertebrate Skeletal Muscle Multinucleated muscle cells (fibers) made up of longitudinal bundles (myofibrils) ___________: basic contractile unit of skeletal muscle Thick filament Myosin Thin filament Actin

Sliding Filament Model of Muscle Contraction Thick filaments (myosin) Thin filaments (actin)

Myosin head bound to ATP in low-energy configuration Myosin head hydrolyzes ATP to ADP, which causes the head to change to the high-energy configuration Myosin head binds to Actin at binding site forming cross-bridge Myosin releases ADP and phosphate, which returns myosin to the low-energy position and causes the thick filament to slide along the thin filament ATP binds to myosin head causing it to release from the Actin binding site Myosin heads form and reform connections with actin (cross-bridge) at a rate of about 5 per second

Role of Calcium ions in Muscle Function Tropomyosin: regulatory protein that covers ________________ when at rest Troponin complex: regulatory proteins on tropomyosin with Ca2+ binding sites Cause tropomyosin to _____ when bound to Ca2+

Types of Skeletal Muscle Oxidative: rely on aerobic respiration for ATP ____________: oxygen-storing protein Glycolytic: rely on ___________ respiration (glycolysis) for ATP Fast twitch: rapid, brief, powerful contractions Slow twitch: slow reaction, but longer contraction )

Muscles and Skeletal Movement Antagonistic muscle arrangement works to extend and contract skeletal muscle

Check Your Understanding Which of the following tissue types are used for lining? a. Epithelial tissue b. Connective tissue c. Nervous tissue d. Muscle tissue

Check Your Understanding Which of the following types of epithelial tissue are specialized for secretion and line the thyroid and salivary glands ? a. Simple cuboidal b. Pseudostratified columnar c. Simple squamous d. Stratified columnar

Check Your Understanding Which of the following types of connective tissue connect muscle to bone? a. Loose connective tissue b. Fibrous connective tissue c. Cartilage d. Skeletal muscle