Post on 27-Mar-2015
transcript
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
The Animal Body and How It Moves
Chapter 22
Copyright © McGraw-Hill Companies Permission required for reproduction or display
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Outline
• Animal Body Plan• Vertebrate Body Organization• Vertebrate Organ Systems• Epithelium• Connective Tissue• Muscle Tissue• Nerve Tissue• Skeletal System
Bones and Muscles
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Radial Versus Bilateral Symmetry
• Radial Symmetry - body parts are arranged around a central axis.
• Bilateral Symmetry - body has a right and left half that are mirror images of each other. Allows different organs to be located in
different parts of the body. Allows for more efficient movement. Allows for cephalization - evolution of
definite head and brain area.
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Body Cavity Versus No Cavity
• Presence of body cavity allows dramatic expansion of portions of digestive tract. Allows for more storage and time for
enzymatic activity for enhanced digestion.- Allows animals to eat more during safe
periods. Allows space for gonad expansion.
- Diverse breeding strategies.
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Body Cavity Versus No Cavity
• Kinds of Body Cavities Acoleomates - No body cavity. Pseudocoelomate - Body cavity located
between endoderm and mesoderm. Coelomates - Body cavity forms entirely
within mesoderm.
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Nonsegmented Versus Segmented Bodies
• Advantages of early embryonic segmentation: Each segment may develop a more or less
complete set of adult organ systems. Locomotion is more effective because of
increased flexibility.
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Protostomes Versus Deuterstomes
• Deuterstomes evolved from protostomes more than 630 mya. Differ fundamentally in three aspects of embryonic growth. Cleavage Blastophore determination of body axis Developmental fate of embryo
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Vertebrate Body Organization
• General Architecture Food flows from in tube from mouth to anus.
- Suspended in coelom, divided into: Thoracic cavity (heart and lungs) Abdominal cavity (stomach intestines)
- Supported by skeleton made up of jointed bones.
- Skull protects brain.- Vertebral column protects spinal cord.
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Vertebrate Body Organization
• Tissues Cells of same type organized into tissues. Three fundamental layers
- Endoderm- Mesoderm- Ectoderm
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Vertebrate Body Organization
• Adult tissues grouped into four general classes: Epithelial Connective Muscle Nerve
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Vertebrate Body Organization
• Organs Body structures composed of several
different tissues grouped together into a larger structural and functional unit.
• Organ Systems Group of organs that work together to carry
out important function.
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Vertebrate Organ Systems
• Skeletal Bones, Skull, Cartilage, Ligaments
• Circulatory Heart, Blood Vessels, Blood
• Endocrine Pituitary, Adrenal, Thyroid Glands
• Nervous Nerves, Brain, Spinal Cord
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Vertebrate Organ Systems
• Respiratory Lungs, Trachea
• Immune Lymphocytes, Macrophages, Antibodies
• Digestive Mouth, Esophagus, Stomach, Intestines,
Liver, Pancreas• Urinary
Kidneys, Bladder
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Vertebrate Organ Systems
• Muscular Skeletal, Cardiac, and Smooth Muscle
• Reproductive Testes, Ovaries
• Integumentary Skin, Hair, Nails, Sweat Glands
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Epithelium
• Outside of body covered with cells developed from embryonic ectoderm tissue.
• Body cavity lined with cells developed from embryonic mesoderm tissue.
• Hollow inner core of digestive tract lined with cells developed from embryonic endoderm tissue.
• Collectively termed epithelium.
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Epithelium
• Epithelium Functions: Protect tissues from dehydration and
mechanical damage. Provide sensory surfaces. Secrete materials.
• Types of Epithelial Cells: Squamous Cubodial Columnar
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Epithelium
• Three general kinds of Epithelial Tissue: Simple Epithelium
- Single cell layer thick - lining lungs and major body cavities.
Stratified Epithelium- Complex layer of cells - skin.
Glands- Secretion
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Connective Tissue
• Connective tissue cells fall into three functional categories: Immune System - Defense Skeletal System - Support Blood and Fat - Storage and Distribution
• Immune System Macrophages - Engulf and digest invaders. Lymphocytes - Produce antibodies and
attack virus-infected cells.
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Connective Tissue
• Skeletal Connective Tissue Fibroblasts - Secrete structurally strong
proteins into spaces between cells. Cartilage - Collagen matrix forms long
parallel arrays along lines of stress. Bone - Collagen fibers coated with calcium
phosphate.
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Connective Tissue
• Storage and Transport Connective Tissues Adipose Tissue - Fat accumulating cells. Erthrocytes - Red blood cells that transport
oxygen and carbon dioxide in blood.- Move in plasma.
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Muscle Tissue
• Distinguishing characteristics of muscle cells is abundance of contractible protein fibers (Microfilaments). Shortening of fibers produces considerable
force.• Kinds of Muscle Cells
Smooth - Microfilament loosely organized. Skeletal and Cardiac - Microfilaments
bunched into myofibrils (Striated Muscle).
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Nerve Tissue
• Composed of two types of cells: Neurons - Specialized for transmission of
nerve impulses. Glial Cells - Supply neurons with nutrients,
support, and insulation.• Neuron plasma membranes are rich in ion-
selective channels that maintain voltage difference between cell interior and exterior.
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Nerve Tissue
• Each neuron composed of: Cell Body - Contains nucleus. Dendrites - Bring nerve impulses to cell. Axon - Carries nerve impulses away.
- Nerve is made of axons of many neurons.• Gaps (synapses) separate neurons.• Neurons communicate by passing
neurotransmitters across the gap.
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Types of Skeletons
• Hydraulic - Fluid-filled cavity encircled by muscle fibers.
• Exoskeletons - Rigid hard case surrounding body.
• Endoskeletons - Rigid internal skeleton.
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Types of Skeletons
• Human Skeleton Made up of 206 individual bones.
- Axial Skeleton (80 bones) support main body axis.
Skull, Backbone, and Rib Cage.- Appendicular Skeleton (126 bones)
support arms and legs. Pectoral girdle Pelvic girdle
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Structure of Bone
• Bone is produced when needle-shaped crystals surround and impregnate collagen fiber. Outer bone layer is dense and compact
(compact bone). Interior of bone is open lattice structure
(spongy bone).
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Structure of Bone
• New Bone Formed in Two Stages: Collagen secreted by osteoblasts which
lay down matrix of fibrils. Calcium minerals impregnate fibrils.
- Layers form as series of tubes around narrow central channel (Haversian Channel) running parallel to length of bone.
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Structure of Bone
• Two cell types responsible for bone remodeling during growth: Osteoblasts - Deposit bone. Osteoclasts - Secrete enzymes that digest
organic matrix of bone, liberating calcium for reabsorption.
• Osteoporosis - Excessive bone loss usually associated with aging.
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Bone Structure
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Kinds of Muscle
• Skeletal Muscle - Move bones of the skeleton. Each muscle fiber consists of many
elongated myofibrils, in turn composed of many myofilaments.
- Contains protein filaments actin and myosin.
• Cardiac Muscle - Composed of chains of single cells organized into fibers that branch and interconnect. Coupled by gap junctions.
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Kinds of Muscle
• Smooth Muscle - Contain long, spindle-shaped cells. Individual myofilaments are not aligned into orderly assemblies, but into sheets. Some contract only when stimulated by a
nerve or hormone.
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Kinds of Muscle
• Tendons Straps of densely connective tissue
attaching muscles to bones. Bones pivot about flexible joints, pulled back
and forth by muscles.- Origin attached by tendon to stationary
bone.- Insertion attached to bone that moves
during muscle contraction.
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Skeletal Muscle Organization
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Skeletal Muscle Organization
• Muscles in movable joints of vertebrates are attached in opposing pairs: Flexors and Extensors
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
How Muscles Work
• When myosin filaments contract heads of myosin filaments move first, moving them closer in the direction of the flex.
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
How Muscles Work
• Nerve fibers embedded in surface of muscle fiber forming neuromuscular junction. When signal reaches end of neuron,
neuron releases acetylcholine into gap separating neuron from muscle.
- Depolarization
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
How Muscles Work
• Role of Calcium Ions in Contraction When muscle is relaxed, attachment sites
for myosin heads are physically blocked by tropomyosin.
- In order to contract a muscle, troponin must move tropomyosin.
Complex regulated calcium ion concentration.
Muscle fibers store Ca++ in sarcoplasmic reticulum.
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Calcium Controls Muscle Contraction
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Review
• Animal Body Plan• Vertebrate Body Organization• Vertebrate Organ Systems• Epithelium• Connective Tissue• Muscle Tissue• Nerve Tissue• Skeletal System
Bones and Muscles
Johnson - The Living World: 3rd Ed. - All Rights Reserved - McGraw Hill Companies
Copyright © McGraw-Hill Companies Permission required for reproduction or
display