ANIMAL TISSUES Copyright © 2009 Pearson Education, Inc.

20.1 Structure fits function at all levels of organization in the animal body  Anatomy—structure  Physiology—function  Animals consist of a hierarchy of levels of organization Copyright © 2009 Pearson Education, Inc.

Cellular level: Muscle cell A An example of structural hierarchy in a pelican

Tissue level Muscle tissue AB Cellular level Muscle cell An example of structural hierarchy in a pelican

A B C Cellular level Muscle cell Tissue level Muscle tissue Organ level Heart

A B C D An example of structural hierarchy in a pelican Organ system level Circulatory system Organ level Heart Tissue level Muscle tissue Cellular level Muscle cell

Organism level Many organ systems functioning together A B C D E Organ system level Circulatory system Organ level Heart Tissue level Muscle tissue Cellular level Muscle cell An example of structural hierarchy in a pelican

20.2 EVOLUTION CONNECTION: An animal’s form reflects natural selection Sharks, seals, and penguins have streamlined, tapered bodies Copyright © 2009 Pearson Education, Inc. Video: Galápagos Sea Lion Video: Shark Eating a Seal

20.3 Tissues are groups of cells with a common structure and function Copyright © 2009 Pearson Education, Inc.  Animals have four main categories of tissues: 1.Epithelial tissue 2.Connective tissue 3.Muscle tissue 4.Nervous tissue

20.4 Epithelial tissue covers the body and lines its organs and cavities Epithelial cells come in three shapes: 1.Squamous—like a fried egg 2.Cuboidal—as tall as they are wide 3.Columnar—taller than they are wide Copyright © 2009 Pearson Education, Inc.

Apical surface of epithelium Cell nuclei Underlying Tissue Basal lamina Simple squamous epithelium (air sacs of the lung) Simple cuboidal epithelium (kidney Simple columnar epithelium (intestine Stratified squamous epithelium (esophagus Pseudostratified ciliated columnar Epithelium (respiratory tract) A B C D E Types of epithelial tissue

Stratified epithelial cells are stacked on top of each other Copyright © 2009 Pearson Education, Inc Epithelial tissue covers the body and lines its organs and cavities

E Types of epithelial tissue; Stratified squamus epithelium (lining the esophagus) Stratified squamous epithelium (esophagus

20.5 Connective tissue binds and supports other tissues Connective tissue can be grouped into six major types Copyright © 2009 Pearson Education, Inc.

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

20.6 Muscle tissue functions in movement Skeletal muscle: causes voluntary movements. Cardiac muscle: pumps blood. Smooth muscle: moves walls of internal organs, such as the intestines. Copyright © 2009 Pearson Education, Inc.

Unit of muscle contraction Nucleus Junction between two cells Nucleus Muscle fiber Cardiac muscle Skeletal muscle C B A The three types of muscle Muscle fiber

20.7 Nervous tissue forms a communication network Neurons carry signals by conducting electrical impulses. Supporting cells insulate axons and nourish neurons Copyright © 2009 Pearson Education, Inc.

Cell body Nucleus Neurons in the spinal cord

20.8 Organs are made up of tissues Each tissue performs specific functions. The heart has epithelial, connective, and nervous tissues: 1.Epithelia line the heart chambers 2.Connective tissues make the heart elastic 3.Neurons regulate contractions Copyright © 2009 Pearson Education, Inc.

Small intestine Lumen Epithelial tissue Connective tissue Smooth muscle tissue 2Layers Connective tissue Epithelial tissue (columnar epithelium Lumen Tissue layers of the small intestine wall

Artificial skin: Used to heal burn 20.9 CONNECTION: Bioengineers are learning to produce tissues and organs for transplants Copyright © 2009 Pearson Education, Inc. laboratory-grown bladder

PLANT TISSUES Copyright © 2009 Pearson Education, Inc.

31.5 Three tissue systems make up the plant body 1.Dermal tissue: – Outer protective covering 2.Vascular tissue: – Support and long-distance transport 3.Ground tissue: –Bulk of the plant body –Food production, storage, support

Copyright © 2009 Pearson Education, Inc Three tissue systems make up the plant body Dermal tissue: –Layer of tightly packed cells called the epidermis. –First line of defense against damage and infection –Waxy layer called cuticle on top of epidermis, reduces water loss

Copyright © 2009 Pearson Education, Inc Three tissue systems make up the plant body 1.Vascular tissue: –Composed of xylem and phloem –Arranged in bundles 2. Ground tissue: –Lies between dermal and vascular tissue –Eudicot stem ground tissue is divided into pith and cortex –Leaf ground tissue is called mesophyll

Eudicot leaf Xylem Phloem ا Vein Guard Cells Stoma Sheath Eudicot stem Vascular bundle Pith Cortex Epidermis Eudicot root Endodermis Cortex Epidermis Phloem Xylem cylinder Mesophyll Cuticle Upper epidermis ا Lower epidermis Monocot stem Vascular Bundle Epidermis Key Ground tissue system Dermal tissue system Vascular tissue system The three plant tissue systems

Eudicot leaf Xylem Phloem Vein Guard Cells Stoma Sheath Mesophyll Cuticle Upper epidermis Lower epidermis Key Ground tissue system Dermal tissue system Vascular tissue system The three plant tissue systems

Eudicot stem Vascular bundle Pith Cortex Epidermis Monocot stem Vascular Bundle Epidermis Key Ground tissue system Dermal tissue system Vascular tissue system The three plant tissue systems

Eudicot root Endodermis Cortex Epidermis Phloem Xylem Vascular cylinder Key Ground tissue system Dermal tissue system Vascular tissue system The three plant tissue systems

Copyright © 2009 Pearson Education, Inc Three tissue systems make up the plant body Plants cells have three structures that distinguish them from animals cells: 1.Chloroplasts used in photosynthesis 2.A large, fluid-filled vacuole 3.A cell wall composed of cellulose

Copyright © 2009 Pearson Education, Inc Plant cells and tissues are diverse in structure and function Plant cell wall –Some plant cell walls have two layers –Primary cell wall—outermost layer –Secondary cell wall—tough layer inside primary wall –A sticky layer called the middle lamella lies between adjacent plant cells –Openings in cell walls called plasmodesmata allow cells to communicate and exchange materials easily

Pit Plasmodesmata Plasma membrane Cell walls of adjoining cells Secondary cell wall Middle lamella Cell walls Primary cell wall Central vacuole Chloroplast Nucleus Endoplasmic reticulum Mitochondrion Golgi apparatus Ribosomes Microtubules Plasma membrane The structure of a plant cell

Copyright © 2009 Pearson Education, Inc. Plant cell structure is related to function. There are five major types of plant cells: 1.Parenchyma cells 2.Collenchyma cells 3.Sclerenchyma cells 4.Water-conducting cells 5.Food-conducting cells 31.6 Plant cells and tissues are diverse in structure and function

Copyright © 2009 Pearson Education, Inc Plant cells and tissues are diverse in structure and function Parenchyma cells: –The most abundant cell type –Have thin primary cell wall –Lack secondary cell wall –A live at maturity –Function in photosynthesis, food and water storage

Starch-storing vesicles Primary cell wall (thin) Pit Parenchyma cell

Copyright © 2009 Pearson Education, Inc. Collenchyma cells: –Have unevenly thickened primary cell wall –Lack secondary cell wall –A live at maturity –Provide flexible support 31.6 Plant cells and tissues are diverse in structure and function

Primary cell wall (thick) Collenchyma cell

Copyright © 2009 Pearson Education, Inc. Sclerenchyma cells : –Have thick secondary cell wall that contain lignin, (lignin is a main component of wood( –It is dead at maturity –Rigid support –There are two types of sclerenchyma cells: fibers and sclereids. –Fibers—long and thin, arranged in bundles. –Sclereids—shorter than fibers, present in nut shells and pear tissue Plant cells and tissues are diverse in structure and function

Primary cell wall Sclereid Pits Secondary cell wall Sclereid cells Secondary cell wall Pits Primary cell wall Fiber Fiber cells Sclerenchyma cells: fiber (left) and sclereid (right)

Secondary cell wall Pits Primary cell wall Fiber Fiber cells Sclerenchyma cells: fiber

Primary cell wall Sclereid Pits Secondary cell wall Sclereid cells Sclerenchyma cells: sclereid (right)

Copyright © 2009 Pearson Education, Inc. Water conducting cells: tracheids and vessel elements: –Both have thick secondary cell walls –Both are dead at maturity –Chains of tracheids and vessel elements form tubes that make up the vascular tissue called xylem 31.6 Plant cells and tissues are diverse in structure and function

Pits Tracheids Vessel element Openings in end wall Water-conducting cells

Copyright © 2009 Pearson Education, Inc. Food-conducting cells: Sieve tube members: –No secondary cell wall –A live at maturity but lack most organelles –Companion cells: –Contain organelles –Control operations of sieve tube members. –Chains of sieve tube members, separated by porous sieve plates, form the vascular tissue called phloem 31.6 Plant cells and tissues are diverse in structure and function

Cytoplasm Primary cell wall Companion cell Sieve plate Food-conducting cell (sieve-tube member)

Meristematic tissues: These are located at the tips of roots and stems, between the water- and food-conducting tissues of stems, and at various other places in plant bodies 31.6 Plant cells and tissues are diverse in structure and function

Locations of apical meristems, which are responsible for primary growth Axillary buds Terminal bud Root tips Black Arrows = direction of growth

Cellulose fibers Key Ground tissue system Dermal tissue system Vascular tissue system Apical meristem Region Zone of elongation Zone of maturation Zone of cell division Root cap Epidermis Cortex Vascular cylinder Root hair Primary growth of a root

Meristematic cells are small, thin-walled, frequently cubical, densely packed with protoplasm, and capable of producing new cells by cell-division. permanent tissues do not become changed into other kinds of tissues as do Meristematic tissues. (source of differentiation :they give rise to all other kinds of tissues) 31.6 Plant cells and tissues are diverse in structure and function

Microscopic photographs of the meristematic cells in the tip of onion roots showing cell division (Arrows) 31.6 Plant cells and tissues are diverse in structure and function