Transcript Document

The Animal Body Tour
Levels of structure
• Cells
• Tissues: Cells combined in distinct ways into
layers. Specialization (division of labor)
• Organs: Made of more than one kind of
tissue. Perform common function.
• Organ systems: Several organs combine to
perform major body function.
Levels of structure
• Example, circulatory system
Levels of structure
• 11 organ systems
Tissue types (4)
• 1) Epithelial tissue
– Covers outer and inner ____________ of body
– Cells tightly joined together (no blood vessels in
intercellular spaces: materials must diffuse in and
out)
– Two major types: covering and lining, and
glandular
Tissue types
• 1) Epithelial tissue types (covering and lining)
– Simple epithelial (1 cell layer). Further subdivided
based on cell shape
• Squamous (flattened)
• Cuboidal (cube shaped)
• Columnar (rectangular)
Tissue types
• 1) Epithelial tissue types (covering and lining)
– Stratified epithelial (multiple cell layers). Further
subdivided by cell shape
• Ex., squamous (flattened)
– Pseudostratified epithelial (one cell layer but looks
like 2 because __________ not all in same position)
• Ex., pseudostratified columnar (rectangular)
Tissue types
• 1) Epithelial tissue
– Glandular (secretes materials) epithelial tissue
• Exocrine glands: connected to epithelium surface by
duct (Ex., sweat glands, salivary glands)
• Endocrine glands: not connected to epithelium surface
(Ex., adrenal gland of kidney). Secretions called
hormones, enter blood and stay within body
Tissue types
• Epithelial tissue functions:
– Protection: invasion, dehydration, physical injury, etc.
– Secretion of chemicals: ex., digestive tract
• Note: usually with great regenerative ability
– Ex., stomach lining replaced every ______ days
Tissue types
• 2) Connective tissue
– Used to bind and support all other tissues
– Other special functions too
– Composed of cells and matrix (extracellular
material)
• Two types:
– Connective tissue proper
– Special connective tissues
Tissue types
• Connective tissue proper
– 1) Loose connective tissue
• Matrix often contains: collagen (strong protein
fibers), elastin (elastic protein fibers)
Tissue types
• Connective tissue proper
– 1) Loose connective tissue
• Cells include: ______________ (cells that secrete
matrix), mast cells (make histamine: blood vessel
dilator), macrophages (phagocytic cells), adipose
cells (contain a fat droplet)
Adipose
Loose connective
Tissue types
• Connective tissue proper
– 2) Dense connective tissue
• Collagen fibers tightly packed (very strong)
• Ex, tendons and ligaments
Tissue types
• Special connective tissues: cartilage
– Matrix: collagen fibers in parallel arrays and
glycoproteins
Tissue types
• Special connective tissues: cartilage
– Chondrocytes: living cartilage cells. Live in
chambers (lacunae). Note lack of blood vessels:
diffusion supplies cells with materials (slow
process!)
Tissue types
• Special connective tissues: bone
– Matrix hardened with calcium phosphate salts
– No __________ occurs through bone matrix. Blood
vessels present in central canals
Tissue types
• Special connective tissues: bone
– Cells called osteocytes, located in chambers (lacunae)
– Osteocytes connect with cellular processes through
canalaliculi
Tissue types
• Special connective tissues: blood
– Blood is connective tissue, with fluid matrix (plasma)
– Erythrocytes (red blood cells): carry oxygen and
carbon dioxide
– Leukocytes (white blood cells): ___________ cells
– Thrombocytes (platelets): fragments of bone marrow
cells
Tissue types
• Connective tissue functions:
–
–
–
–
Connect parts (tendons connect muscle to bone)
Support body (skeleton)
Protection (cranium around brain)
Circulate materials (blood).
Tissue types
• 3) Muscle tissue
– Most abundant _________ in humans
– Basic structure: bundles of myofibrils, composed of
protein filaments (actin and myosin).
Tissue types
• 3) Muscle tissue types:
– Skeletal (striated) muscle: multinucleated,
produce voluntary movements
Tissue types
• 3) Muscle tissue types:
– Cardiac (also striated): single nucleus, have
intercalated discs (heart muscle)
Tissue types
• 3) Muscle tissue types:
– Smooth muscle: no striations. Usually not
under voluntary control
Tissue types
• Functions:
– Movement (of body, fluids within body, etc.)
Tissue types
• 4) Nerve tissue
–
–
–
–
Transmits electrochemical impulses
Neuron (name of cell type)
Dendrite (process: brings impulse to cell body)
Axon (process: carries impulse from cell body)
Tissue types
• 4) Nerve tissue
– Neuroglia: support cells
– Often associate with axons, form sheath
(_________ sheath)
– Note Nodes of Ranvier (gaps in sheath).
Tissue types
• 2 nerve networks:
– Peripheral Nervous System (PNS): perceives
environment and communicates to body
– Central Nervous System (CNS): processes
information and coordinates activities
Tissue types
• 4) Nerve tissue:
Types of neurons
– Sensory (receive
information: send
to CNS)
– Motor (stimulate
muscles/glands)
– Association
(integrate
information and
connect to other
neurons)
Tissue types
• 4) Nerve tissue
– Nerves: bundles of ___________
– Ganglion (plural: ganglia): collection of neuron
cell bodies
Tissue types
• 4) Nerve tissue
– Functions: Send electrical signals to convey
information, make things happen in body, etc.
Integumentary System
Integumentary System
• Human skin: largest organ of body (2 square
yards, 16% of body weight)
• Distribution: “Rule of _____s”
Note: diagram %s are for
only one side of body
Integumentary System
• Many functions in animals:
– Protection. Forms boundary of individual,
barrier to external dangers and valuable internal
materials
– Sensing. Can gather information about
environment: temperature, pressure, light,
damage to integument
– Communication. Since visible to others, can
send signals with skin color or structures (hairs,
scales, feathers)
– Regulate body temperature. Can be used to
gain/lose energy. Integument structures (hairs,
scales, feathers) can provide ____________
Integumentary System
• Many functions in animals:
– Excretion: Sweat contains water, urea
(nitrogenous waste material), salts. These
eliminated during sweating
Integumentary System
• Skin layers
– Epidermis
– Dermis
Integumentary System
• Human skin layers: Epidermis
– Upper boundary: Stratum corneum. Dead cells
that provide protective layer. Shed as skin
scales or flakes
Integumentary System
• Human skin layers: Epidermis
– You will shed about 40 lbs. of skin scales
during your lifetime
– Good news for dust mites (Phylum Arthropoda,
Class Arachnida, Order Acari)!
Integumentary System
• Human skin layers: Epidermis
– Lower boundary: Stratum germinativum (basal cells).
Living cells doing rapid _________. Daughter cells
fill with keratin (tough water resistant protein: also
found in hair, fingernails, hooves, claws), flatten and
die
Integumentary System
• Human skin layers: Epidermis
– Contains melanocytes: cells that produce melanin
and transfer it to other skin cells. Darken skin color
in response to UV exposure (tanning)
Integumentary System
• Human skin layers: Epidermis
– UV exposure increases skin cancer chances
– Melanoma: ____________ that divides out of control
– Recall ozone thinning problem
Integumentary System
• Human skin layers: Dermis
• Contains connective tissue, blood vessels,
nerve endings.
Integumentary System
• Human skin also contains:
hairs
– Follicle: invagination of skin
surface containing hair
– Shaft: body of hair (mostly
protein: ____________)
– Bulb: base from which hair
grows by cell division (each
cell divides every 1-3 days!)
– Papilla: contains blood supply
Integumentary System
• Human skin also contains:
hairs
– Arrector pili muscle:
smooth muscle. Can
change angle of hair
Integumentary System
• Human skin also contains: exocrine glands
– Sweat glands: empty onto skin surface at sweat
pore.
Integumentary System
• Human skin also contains: exocrine glands
– Sebaceous glands: associated with hair follicle,
secrete oil to lubricate/protect skin and hair
Integumentary System
• Human skin also contains: sense organs
– Free nerve endings: sense _____________
– Hair follicle receptors: can sense movement of
hair
Integumentary System
• Human skin also contains: sense organs
– Merkel cell, Meissner’s corpuscles, Pacinian
corpuscles. Sense pressure/stretch of skin
Integumentary System
• Human skin also contains: sense organs
– Temperature: End-bulb of Krause (cold), Organ
of Ruffini (hot)
Integumentary System
• Below the skin: Subcutaneous __________
• Contains adipose tissue
– Stores energy, cushioning (soles of feet, palms
of hands), provides insulation
Integumentary System
• Nails: Special keratinized layer of cells
produced by fold of skin (nail root)
Fingernail magnified
1000 X
Skin burns
• First degree (epidermis), second degree
(epidermis), third degree (dermis)
Skeletal System
Skeletal System
• Contains mostly connective tissue
–
–
–
–
Bone
Cartilage
Tendons (connect bone to muscle)
Ligaments (connect one bone to another bone)
Bone
• Living tissue. Contains nerves, blood vessels,
cells
• Formed by cells called ___________, which
secrete collagen matrix in which Ca and P salts
later deposited. These cells then called osteocytes.
• Usually forms by replacing cartilage in embryo
and at ends of major bones as they grow
(endochondral bones)
• Some bones formed directly from dense
connective tissue (intramembranous bones)
• Structure
Bone
– Periosteum: connective tissue sheath
• Structure
Bone
– Compact bone (along shafts of long bones)
• hollow inner core with yellow marrow
• Structure
Bone
– Compact bone
• Bone laid down in layers called lamellae in an
_______ or Haversian system
• Structure
Bone
– Compact bone
• Haversian systems: structural unit that surrounds
internal marrow cavity or spongy bone. Haversian
Canal contains blood vessels and nerves
• Volkmann’s canals: connect adjacent Haversian canals
• Structure
Bone
– Spongy bone
• Mainly at outer ends of long bones
• Cavities contain red marrow
• All areas of bones start as spongy bone, some
become compact bone as they develop
• Structure
Bone
– Marrow (in bone spaces)
• Red marrow: stores fat, makes _______ cells
(red and white) by rapid mitotic divisions
• Yellow marrow: stores fat only
Bone
• Long bones grow in length in areas toward ends
at ____________ plates
• Cartilage there grows, chondrocytes die,
osteoblasts move in and secrete bone. Process
stops by age 20.
Bones
• 206 bones in human body
Bones
• In lab: use rat skeleton (240 bones total). Need to
know names of bones and groups shown in
manual. DO BEFORE COMING TO LAB!
Cartilage
• Generally, firm but flexible connective tissue
• Cells called chondrocytes
• Contains collagen and elastin fibers in matrix
• 4 types:
Cartilage
– 1) Hyaline cartilage. Flexible, translucent. High in
___________ fibers (tough and strong)
– Ex, rings in trachea (windpipe). Seen in lab rat
– Ex, found between bones in many joints (cushions
bone). Knee joint (articular cartilage).
Cartilage
• 4 types
– 2) Elastic cartilage. High in __________ fibers. Flexible.
Ex, outer ear
– 3) Fibrocartilage. High in collagen, not translucent. Very
tough. Used to cushion some joints (vertebrae)
– 4) Calcified cartilage. Has some calcium deposits, but not as
much as bone. Ex, Chondrichthyes (cartilagenous fishes)
Elastic cartilage
Tendons
• Connect bones to adjacent
muscles. All major muscles
attached to skeleton this way.
• Ex, muscles that work fingers
are in lower arm. Attach to
fingers by tendons that you can
see on the back of your hand
Ligaments
• Hold adjacent bones together. Can determine how
bones move (ex, knee joint)
• Tend to stretch in one direction
Ligaments/Tendons
• Similar, in that little to no ________ supply
present
• So, very slow to heal if damaged. Also, scar
tissue that does form is not very strong
• However, easily replaced by transplants
(from cadavers or other living humans)
Joints
• Also called articulations. Where one bone meets another.
• 3 types:
• 1) Immovable joints. __________ tissue joints bones. Ex,
sutures in skull
Joints
• Also called articulations. Where one bone meets another.
• 2) Slightly movable joints. Bones bridged by cartilage.
Ex, intervertebral discs in backbone. Allow some
movement, cushion vertebrae.
Joints
• 3) Freely movable joints (synovial joints).
– Bone tipped with layer of ____________
– End encased in synovial capsule: Fluid-filled membrane
bag. Ex, finger as hinge-like joint (movement in one
direction). Hip joint as ball and socket joint (rotating
movement possible).