HUMAN BODY Climbing the walls? Spiderman is able to climb walls

The explanation: 1.Hairs (called setae) on gecko’s toes contain split ends (called spatulae) 2. ability to “stick” to surfaces from attractions between molecules on the spatulae and the surface on which the gecko is crawling

–Correlation between structure and function –Human structure has a hierarchy: Cell Tissues Organs Organ sytems

TISSUES groups of cells with a common structure and function Main types: –Epithelial –Connective –Muscle –Nervous

Epithelial tissue sheets of closely packed cells covers the body and l ines the cavities and tubes of internal organs Functions in protection, secretion, and exchange

A Simple squamous epithelium (lining the air sacs of the lung) B Simple cuboidal epithelium (forming a tube in the kidney) C Simple columnar epithelium (lining the intestine) D Stratified squamous epithelium (lining the esophagus) Layers of dead cells Rapidly dividing epithelial cells E Stratified squamous epithelium (human skin)

Connective tissue binds and supports other tissues various types characterized by sparse cells in an extracellular gel matrix

Cartilage- forming cells Matrix D. Cartilage (at the end of a bone) Central canal Matrix Bone- forming cells E. Bone F.Blood A. Loose connective tissue (under the skin) Collagen fiber Cell Collagen fibers Cell nucleus B. Fibrous connective tissue (forming a tendon) White blood cells Red blood cell Plasma C. Adipose tissue Fat droplets

Muscle tissue functions in movement Types: –Skeletal muscle is responsible for voluntary body movements –Cardiac muscle pumps blood –Smooth muscle moves the walls of internal organs such as the stomach

Unit of muscle contraction Muscl e fiber Nucleus A Skeletal muscle Nucleus Muscle fiber Junction between two cells Muscle fiber Nucleus C Smooth muscle B Cardiac muscle

Cell body Nucleus Cell extensions LM 330  Nervous tissue forms a communication network the branching neurons transmit nerve signals that help control body activities

Artificial tissues have medical uses: c an assist in the healing of several injuries

ORGANS –Each organ is made of several tissues –collectively perform specific functions Small intestine (cut open) Lumen Epithelial tissue (columnar epithelium) Connective tissue Smooth muscle tissue (2 layers) Connective tissue Epithelial tissue Lumen

ORGAN SYSTEMS Organ systems work together to perform life functions 1.Digestive 2.Respiratory 3.Circulatory 4.Lymphatic 5.Immune 6.excretory 7.Endocrine 8.integumentary 9.Skeletal 10.Muscular 11.reproductive

–digestive and respiratory systems: gather food and oxygen A Digestive system Mouth Esophagus Liver Stomach Small intestine Large intestine Anus B Respiratory system Nasal cavity Larynx Trachea Bronchus Lung

–The circulatory system, aided by the lymphatic system Transports the food and oxygen –The immune system Protects the body from infection and cancer C Circulatory system Heart Blood vessels E Lymphatic system D Immune system Bone marrow Thymus Spleen Lymph nodes Lymph vessels

–The excretory system Disposes of certain wastes –The endocrine and nervous systems Control body functions F Excretory system Kidney Ureter Urinary bladder Urethra Pituitary gland Thymus Thyroid gland Testis (male) Adrenal gland Pancreas G Endocrine system Ovary (female)

–The integumentary system Covers and protects the body –Skeletal and muscular systems Support and move the body I Integumentary system Hair Skin Nails K Muscular system Skeletal muscles Cartilage Bones J Skeletal system

–The reproductive system Perpetuates the species Female Vas deferens Penis Urethra Testis Prostate gland Male Oviduct Ovary Uterus Vagina L Reproductive systems

New imaging technology reveals the inner body without surgery X-rays: used for imaging bones and teeth MRI, Magnetic resonance imaging: visualization of soft tissues MRM, Magnetic resonance microscopy: 3-D images of very small structures

CT, Computed tomography scans: excellent diagnostic tools

PET, Positron-emission tomography: Yields information about metabolic processes at specific locations in the body

SKELETON human skeleton: 206 bones –axial skeleton: Skull Backbone rib cage –appendicular skeleton: bones of the arms and legs and the joints where they attach to the axial skeleton –pectoral or shoulder joint –pelvic or hip joint Skull Examples of joints Clavicle Scapula Shoulder girdle Sternum Ribs Humerus Vertebra Radius Ulna Pelvic girdle Carpals Phalanges Metacarpals Femur Patella Tibia Fibula Tarsals Metatarsals Phalanges

–Movable joints Provide the human skeleton with flexibility 123 Ball-and-socket jointHinge jointPivot joint Head of humerus Scapula Ulna Humerus Ulna Radius

Bones are complex living organs: –Cartilage at the ends of bones: Cushions the joints - Bone cells, serviced by blood vessels and nerves Live in a matrix of flexible protein fibers and hard calcium salts –Long bones have a central cavity: to store yellow bone marrow, which is mostly stored fat –Spongy bone contains red marrow: blood cells are made Cartilage Blood vessels Fibrous connective tissue Yellow bone marrow Central cavity Compact bone Spongy bone (red bone marrow) Cartilage

Broken bones can heal themselves: re realigned and immobilized

–Artificial joints: often used to repair severe injuries

Weak, brittle bones are a serious health problem, even in young people Osteoporosis, a bone disease characterized by weak, porous bones

dynamic bone “remodeling” model: going on all the time: –osteoblasts deposit bone –osteoclasts break bone and release calcium –As a person ages, the backbone and other bones tend to decline in mass; excessive bone loss is called osteoporosis

The skeleton and muscles interact in movement: Biceps contracted, triceps relaxed (extended) Triceps contracted, biceps relaxed Biceps Triceps Biceps Tendon

MUSCLES Muscle cells are the motors of the body contractible proteins fibers, myofilaments with the proteins actin and myosin

Muscle Fascicle Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Levels of Functional Organization in a Skeletal Muscle Fiber Muscle Fiber Myofibril Sacromere

3 types: Smooth muscle: walls of blood vessels and the gut Skeletal muscle: move the bones of the skeleton Cardiac muscle: fibers that branch and interconnect to form a network connected, electrical impulses passes from cell to cell causing the heart to contract in an orderly fashion

Skeletal muscles move the bones Tendons: connective tissue that attach muscles to bone Muscle tone: Even at rest, some of the motor units of muscles are always contracting= resting tension

Athletic training increases strength and endurance: causes increases in: - number of mitochondria - concentration of glycolytic enzymes - glycogen reserves - myofibrils

Types of sports fast or white fibers: Large in diameter-densely packed myofibrils Large glycogen reserves few mitochondria Can contract in 0.01 sec following stimulation uses a lot of ATP uses anerobic glycolysis: converts stored glycogen to lactic acid fatigue rapidly because glycogen reserves are limited and lactic acid builds up Slow or red fibers: Only 1/2 the diameter of fast fibers Takes 3 times longer to contract after stimulation abundant mitochondria Uses aerobic metabolism Has a more extensive capillary network Red color due to red pigment of myoglobin

Muscles only pull because myofibrils contract: –muscles in the joints are attached in opposing pairs called flexors and extensors –when contracted they move the bones in different directions

sliding filament model: muscular contraction –the head of a myosin filament binds to an actin filament –ATP is used to flex the myosin head –when the muscle contracts, the myosin head returns to its original shape and pulls the actin it is attached to along with it