lecture 1 animal cell types and tissues
Post on 05-Dec-2014
3.272 Views
Preview:
DESCRIPTION
TRANSCRIPT
Biology 11 (Fundamentals of Biology I)
Lecturer: Ian Kendrich C. Fontanilla, Ph.D. Pav. IV, Room 4113
ANIMALS: Form and Function
Main References: (1) Biology by Campbell and Reece
(2) Integrated Principles of Zoology by Hickman et al.
ANIMALS : Form and FunctionA. Animal Cell Types and TissuesB. Animal Systems and Processes
1. Support and Protection2. Movement3. Digestion and Nutrition4. Gas Exchange5. Transport/Circulation6. Excretion and Osmoregulation7. Regulatory Mechanisms
• Anatomy - the study of the biological form of an organism
• Physiology - the study of the biological functions an organism performs
• The comparative study of animals reveals that form and function are closely correlated
ANIMALS : Form and Function
• Life is characterized by hierarchical levels of organization, each with emergent properties.
1. Protoplasmic grade of organization
Levels of Organization in Organismal Complexity
2. Cellular grade of organization
3. Cell-tissue grade of organization
4. Tissue-organ grade of organization
5. Organ-system grade of organization
1. Protoplasmic grade of organization– unicellular organisms– all life functions are confined within the boundaries
of a single cell– protoplasm is differentiated into organelles
Levels of Organization in Organismal Complexity
Paramecium
2. Cellular grade of organization– aggregation of cells that are functionally
differentiated– a division of labor is evident
Levels of Organization in Organismal Complexity
Volvox
3. Cell-tissue grade of organization– aggregation of similar cells into definite patterns of
layers, thus becoming a tissue
Levels of Organization in Organismal Complexity
4. Tissue-organ grade of organization– an aggregation of tissues into organs
Levels of Organization in Organismal Complexity
Planaria
5. Organ-system grade of organization– organs work together to perform some function– systems are associated with basic body functions
Levels of Organization in Organismal Complexity
Structural Organization in Higher Forms
Structural Unit
Types/Kinds/Examples Field of Study
Organ System
IntegumentaryMuscularSkeletalNervousCirculatoryExcretory
RespiratoryReproductiveDigestiveEndocrineImmune
Anatomy
Organ oral cavitypharynxesophagusstomachpancreasintestines
braineyeliverkidneylunganus
Anatomy
Structural Organization in Higher Forms
Structural Unit
Types/Kinds/Examples Field of Study
Tissue A. Somatic - epithelial - connective - muscular - nervous
B. Reproductive - sperm - egg/oocyte
Histology
Cell same as in tissue Cytology/Cell Biology
Animal Cell Types
Four main categories of animal tissues
1. Epithelial Tissue
2. Connective Tissue
3. Muscular Tissue
4. Nervous Tissue
1. Epithelial Tissue
• covers the outside of the body and lines organs and cavities within the body
• compact; occurs in sheets of tightly packed cells
• little intercellular substance
• polarized
1. Epithelial Tissue
• the free surface of the epithelium is exposed to air or fluid
• structures on free surfaces: microvilli, cilia, flagella
• Basement membrane • where the cells at the
base of the barrier are attached
• also called basal lamina
– cells are closely joined
– animals have 3 main types of intercellular links:
1. tight junctions
2. desmosomes
3. gap junctions
1. Epithelial Tissue
Tight junction
0.5 µm
• membranes of adjacent cells are fused, forming continuous belts around cells
• prevent leakage of extracellular fluid across a layer of epithelial cells
1. Tight Junction
Desmosome1 µm
• fasten cells together into strong sheets, much like rivets
• reinforced by intermediate filaments of keratin
• attach muscle cells to each other in a muscle
2. Desmosomes
Gap junction
0.1 µm
• provide cytoplasmic channels between adjacent cells
• salt ions, sugar, amino acids, and other small molecules can pass through channels
3. Gap Junction
Types according to layering:1. simple epithelium
2. stratified epithelium
1. Epithelial Tissue
- Made up of a single layer of cells
- Made up of many layers of cells
3. pseudostratified epithelium - Made up of a single layer of cells but appears stratified
1. Epithelial Tissue
Types of epithelial cells according to shape:
1. Cuboidal – like dice
2. Squamous – flat like tiles
3. Columnar – like bricks on end
• composed of flattened cells
• form a continuous delicate lining of blood capillaries, lungs, and other surfaces
• permits the passive diffusion of gases and tissue fluids into and out of cavities
Simple squamous epithelium
• consists of 2 to many layers of cells
• adapted to withstand mild mechanical abrasion
• basal layers of cells undergo continuous mitotic divisions
• lines the oral cavity, esophagus, anal canal, vagina of mammals, skin
Stratified squamous epithelium
• short, boxlike cells
• usually lines small ducts and tubules• may have active secretory and absorptive
functions
collecting duct in kidney
Simple cuboidal epithelium
• like cuboidal epithelium but cells are taller
• found on highly absorptive surfaces such as intestinal tract and female reproductive tract
• in some organs, cells may be ciliated
roof of mouth of toad
Simple columnar epithelium
• consists of at least two layers of cells
• found along some areas of the anorectal region and salivary duct
salivary duct
Stratified columnar epithelium
• a type of stratified epithelium
• specialized to accommodate great stretching
• found in the urinary tract and bladder
Transitional epithelium
Glandular epithelia, absorb or secrete chemical solutions
Types based on how products are released:a. exocrine (unicellular or multicellular)
b. endocrinec. mixed (e.g., pancreas)
Special terms of some epithelial tissues:
a. mesothelium – squamous cells lining serous cavities such as peritoneal and pleural cavities and lining of visceral organs
b. endothelium – lining of blood and lymph vessels
• mechanical support
• exchange of metabolites between blood and tissues
2. Connective Tissue
• storage of energy reserve in adipose tissues
• bind structures to preserve integrity of organization
• protection against infection• repair
• paucity of cells; more intercellular substance (fibers and ground substance)
2. Connective Tissue
• the extracellular matrix generally consists of a web of fibers embedded in a uniform foundation that may be liquid, jellylike, or solid
2. Connective Tissue
• amorphous ground substance
- glycosaminoglycans such as chondroitin sulfate
- permit diffusion of nutrients, substances, water, gases, and wastes
- important in areas where small blood vessels are absent
2. Connective Tissue
A. fixed
- fibroblast/fibrocyte- mesenchymal
- adipose
Types of cells:
- fixed macrophage
B. wandering (from blood)
- monocyte- lymphocyte
- plasma cell- eosinophil
- mast cell
Three kinds of connective tissue fibers:• Collagenous fibers (white)
– made of collagen– nonelastic and do not tear easily when pulled
lengthwise
• Elastic fibers (yellow)– long threads of elastin– elastin fiber provides a rubbery quality
• Reticular fibers (branching)– very thin and branched– composed of collagen– they form a tightly woven fabric that joins
connective tissue to adjacent tissues
37
Diagram of Fibrous Connective Tissue
Major types of connective tissues in vertebrates
A. Fibrous connective tissue– dense due to its large
number of collagenous fibers
– the fibers are organized into parallel bundles
– forms tendons and ligaments
Major types of connective tissues in vertebrates
B. Loose connective tissue– binds epithelia to underlying tissues– functions as packing materials, holding organs in
place– has all three fiber types
• two cell types predominate in its fibrous mesh
- fibroblasts- macrophages
Major types of connective tissues in vertebrates
C. Adipose tissue– specialized form of loose
connective tissues that store fat in adipose cells
– pads and insulates the body and stores fuel as fat molecules
– each adipose cell contains a large fat droplet that swells when fat is stored and shrinks when the body uses fat as fuel
Major types of connective tissues in vertebrates
D. Cartilage
– has an abundance of collagenous fibers embedded in a rubbery matrix made of a substance called chondroitin sulfate, a protein-carbohydrate complex
– chondrocytes secrete collagen and chondroitin sulfate
– Types:
1. Hyaline cartilage
2. Elastic cartilage
3. Fibrocartilage
Major types of connective tissues in vertebrates
1. Hyaline cartilage– bluish white, translucent, and homogenous– has significant proportion of collagen fibers– covers joint surfaces and rib ends– present in the nose, larynx, and trachea– skeletal cartilage in the embryos of all vertebrates– skeletal cartilage of adult sharks and rays– support and reinforcement
2. Elastic cartilage– contains fine collagenous fibers and many elastic
fibers– external ears, eustachian tube, epiglottis– maintains a structure’s shape while allowing great
flexibility
3. Fibrocartilage– contains many large collagenous fibers– intervertebral disks, pubic symphysis, disks of knee
joint, and pads between femur and tibia– absorbs compression shock
Collagen fiber
Chondrocyte in lacuna
E. Bone– the skeleton supporting most vertebrates– mineralized connective tissue
Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings
Major types of connective tissues in vertebrates
E. Bone– Osteoblasts are cells that deposit a matrix of
collagen– then, calcium, magnesium, and phosphate ions
combine and harden within the matrix into the mineral hydroxyapatite
– the combination of hard mineral and flexible collagen makes bone harder than cartilage without being brittle
Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings
Major types of connective tissues in vertebrates
F. Blood– Made of:
1. Plasma (55%)– matrix consisting of water, salts, and a variety
of dissolved proteins
2. Formed elements (45%)– erythrocytes, leukocytes and cell fragments
called plateletsCopyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings
Major types of connective tissues in vertebrates
Plasma (55 %)1. water (90% of plasma) 3. gases (O2, CO2, N)
2. dissolved solids
a. proteins–. fibrinogen (synthesized by the liver)–. albumin (synthesized by the liver)–. globulin
b. supplies for cells (glucose, fats and fat-like substances, amino acids, salts)
c. cell products (enzyme, hormones, antibodies)
d. cellular waste products (urea, uric acid)
Blood
Formed elements (45 %) – produced by bone marrow
Blood
Type % Nucleus Cytoplasmic granule/cytoplasm
Other features/functions
A. granulocyte
1. neutrophil 60-75 2-5 or more thin lobes, connected by slender chromatic threads
fine; don’t stain well at neutral pH with either acid or basic stain
phagocytic
2. eosinophil 2-5 2 oval lobes linked by thread-like chromatin
granules, coarse; stain pinkish red with acid stain
against helminthic infections
3. basophil 0.5-2 nuclei stain very faintly, often obscured by cytoplasmic granules; U or J-shaped
stain blue with basic dye
inflammatory reaction
Types of White Blood Cells
Type % Nucleus Cytoplasmic granule/cytoplasm
Other features/functions
B. agranulocyte
1. lymphocyte 20-25 large, somewhat spherical with some indentations and only slightly concentric position
narrow rim of cytoplasm
smallest; antibody production
2. monocyte 3-8 nuclei vary slightly, indented ovals to horse-shoe shaped structure
large amount of cytoplasm
biggest; becomes macrophage; phagocytic
Types of White Blood Cells
• composed of long cells called muscle fibers that are capable of contracting when stimulated by nerve impulses
• most abundant tissue in most animals
3. Muscle Tissue
• muscle contraction accounts for most of the energy-consuming cellular work in active animals
Types of muscles tissue
• has cylindrical and striated cells with multiple nuclei (syncitial)
• occurs in muscles attached to skeleton
• functions in voluntary movement of body
1. skeletal muscle
• single innervation by motor nerve
Types of muscles tissue
• spindle-shaped cells, each with a single nucleus • cells have no striations • double innervation by parasympathetic and
sympathetic nervous system; involuntary • blood vessel walls and walls of the digestive tract • functions in movement of substances in lumens of
body
2. smooth muscle
Types of muscles tissue
• has cylindrical but branching striated cells, each with a single nucleus
• double innervation by parasympathetic and sympathetic nervous system; involuntary
• occurs in the wall of the heart• functions in the pumping of blood
3. cardiac muscle
Types of muscles tissue
• irritability and conductivity; senses stimuli and transmits signals from one part of the animal to another
• neuron – functional unit of nervous tissue
4. Nervous Tissue
4. Nervous Tissue
•Neurons consists of a cell body, dendrites and axons
•Dendrite – transmits nerve impulses from their tips toward the rest of the neuron•Axon – transmits impulses toward another neuron or toward an effector, such as a muscle cell
Types of neurons:• sensory (afferent)• motor (efferent)• interneuron
4. Nervous Tissue
Symmetry– refers to balanced proportions– correspondence in size and shape of parts on
opposite sides of a median plane
Animal Body Plans
• any plane passing through the center divides a body into equivalent or mirrored halves
• found chiefly among some unicellular forms
• rare in animals
• best suited for floating and rolling
Spherical Symmetry
• body can be divided into similar halves by more than two planes passing through the longitudinal axis
• found in some sponges and hydras, jellyfish, sea urchins
• usually sessile, free floating or weakly swimming
Radial Symmetry
• only two planes passing through the longitudinal axis produce mirrored halves because of some part that is single or paired
• comb jellies
Biradial Symmetry
• body can be divided along a sagittal plane into mirrored portions – right and left halves
• much better suited for directional (forward) movement
• strongly associated with cephalization
Bilateral Symmetry
Segmentation
• metamerism
• serial repetition of similar body segments along the longitudinal axis of the body
• segment (metamere or somite)
top related