Presentation on theme: "4/15/2015 Plant and Animal tissue. 4/15/2015 Plant tissue."— Presentation transcript:
4/15/2015 Plant and Animal tissue
4/15/2015 Plant tissue
4/15/2015 General Plant Organization A plant has two organ systems:organ systems 1)the shoot system, includes the organs such as leaves, buds, stems, flowers, and fruits.shoot 2) the root system, includes the roots, tubers, and rhizomes.root Taproot system in dicots
4/15/2015 General Plant Organization Root systemRoot system: 1)Primary – taproot – anchors the plant 2)Hairs – increase the surface area for absorption 3)Adventitious roots – arising above ground from stems and leaves – support the tall stem.
4/15/2015 General Plant Organization Stem systemStem system: Is an alternating system of nodes and internodes Nodes – place of leaf attachment Internodes – segments between nodes In the angle formed by each leaf are axillary buds – they have potential to form a branch. They do not grow. The growth occurs at terminal bud at the apex. They inhibit the growth of axillary buds by the process called apical dominance
4/15/2015 General Plant Organization Modified shoots: Stolons – for a asexual colonization (strawberry) Rhizomes –- underground grown horizontal stems (ginger) Tubers – the swollen ends of rhizomes (potato) Bulbs – vertically grown underground shoots (onion)
4/15/2015 General Plant Organization Leaves: Flattened blade and a stalk (petiole), which joins the leaf to a node of the stem Many monocots (grasses) do not have a petiole Most monocots have parallel veins, whereas dicots have it branched
4/15/2015 General Plant Organization Plant cells are formed at meristems, develop into cell types which are grouped into three tissue types:tissue 1)Dermal (epidermal cells);Dermal 2)Ground (parenchyma, collenchyma, and sclerenchyma cell types); Pith – internal to the vascular tissue and cortex – external to the vascular tissueGround 3)Vascular (xylem, phloem, parenchyma cells, and cambium cells).Vascular
4/15/2015 General Plant Organization Plant cell types rise by mitosis from a meristem.mitosismeristem Apical meristem - at the tip of the shoot or root;Apical meristem Lateral meristem - in cylinders extending nearly the length of the plant.
4/15/2015 Diagram of leaf structure.
4/15/2015 Parenchyma cells A generalized plant cell type, parenchyma cells are alive at maturity.parenchyma They function in storage, photosynthesis, and as the bulk of ground and vascular tissues.photosynthesis Palisade parenchyma cells are elongated cells located just below the epidermal tissue.Palisade parenchyma
4/15/2015 Parenchyma cells Spongy mesophyll cells occur below the one or two layers of palisade cells.Spongy mesophyll Parenchyma cells also occur within the xylem and phloem of vascular bundles.vascular bundles In many prepared slides they stain green.
4/15/2015 Lily Parenchyma Cell (cross-section) (TEM x7,210). This image is copyright Dennis Kunkel
4/15/2015 Collenhyma cells Collenchyma cells support the plant.Collenchyma These cells are characterized by thickenings of the wall, they are alive at maturity. They tend to occur as part of vascular bundles or on the corners of angular stems.
4/15/2015 Comparison of Parenchyma and Collenhyma cells ParenchymaCollenchyma
4/15/2015 Sclerenchyma Sclerenchyma cells support the plant.Sclerenchyma They often occur as bundle cap fibers. Sclerenchyma cells are characterized by thickenings in their secondary walls. They are dead at maturity. They, like collenchyma, stain red in many commonly used prepared slides. A common type of schlerenchyma cell is the fiber.
4/15/2015 Xylem Xylem is a term applied to woody (lignin-impregnated) walls of certain cells of plants.Xylemlignin Xylem cells tend to conduct water and minerals from roots to leaves. They are dead at functional maturity. Tend to stain red with Safranin-O.
4/15/2015 Xylem Tracheids are long and tapered, with angled end-plates that connect cell to cell. Occur early in vascular plants. Vessel elements are shorter, much wider, and lack end plates. Occur only in angiosperms, the most recently evolved large group of plants.
4/15/2015 Xylem Conducting cells of the xylem; tracheids (left) are more primitive, while the various types of vessels (the other three) are more advanced.
4/15/2015 Xylem Conductive Vessel Element in Mountain Mahogany Wood (SEM x750). This image is copyright Dennis Kunkel.
4/15/2015 Phloem Phloem cells conduct food from leaves to rest of the plant.Phloem They are alive at maturity and tend to stain green. Phloem cells are usually located outside the xylem. Cucurbita Stem/Cross Section/ Phloem/Sieve-plateCucurbita Stem/Cross Section/ Phloem/Sieve-plate.
4/15/2015 Phloem The two most common cells in the phloem are the companion cells and sieve cells.companion cellssieve cells Companion cells retain their nucleus and control the adjacent sieve cells. Dissolved food, as sucrose, flows through the sieve cells.
4/15/2015 Epidermal Cells Epidermis The epidermal tissue functions in prevention of water loss and acts as a barrier to fungi and other invaders.epidermal tissue Thus, epidermal cells are closely packed, with little intercellular space. To further cut down on water loss, many plants have a waxy cuticle layer deposited on top of the epidermal cells. cuticle
4/15/2015 Epidermal Cells Guard Cells To facilitate gas exchange between the inner parts of leaves, stems, and fruits, plants have a series of openings known as stomata (singular stoma). stomata Obviously these openings would allow gas exchange, but at a cost of water loss. Guard cellsGuard cells are bean-shaped cells covering the stomata opening. They regulate exchange of water vapor, oxygen and carbon dioxide through the stoma.
4/15/2015 Epidermal Cells SEM of Equisetum (horsetail or scouring rush) Corn leaf epidermal peel
4/15/2015 Pea Leaf Stoma, Vicea sp. (SEM x3,520).
4/15/2015 Epithelial tissue Epithelial tissue covers body surfaces and lines body cavities. Functions include lining, protecting, and forming glands. Three types of epithelium occur: Squamous epithelium is flattened cells. Cuboidal epithelium is cube-shaped cells. Columnar epithelium consists of elongated cells.
4/15/2015 Epithelial tissue Any epithelium can be simple (single cell layer) or stratified (multiple cell layer). Pseudostratified epithelium is a single layer of cells so shaped that they appear at first glance to form two layers.
4/15/2015 Epithelial tissue Single layer of simple cuboidal epithelium Single layer of simple columnar epithelium
4/15/2015 Functions of epithelial cells It includes: movement materials in, out, or around the body. protection of the internal environment against the external environment. Secretion of a product.
4/15/2015 Functions of epithelial cells Glands can be single epithelial cells, such as the goblet cells that line the intestine. Multicellular glands include the endocrine glands. endocrine glands Many animals have their skin composed of epithelium. Vertebrates have keratin in their skin cells to reduce water loss.keratin The mucous membranes lining the oral cavity and nasal passageways secrete mucus which moistens and lubricates the surfaces.
4/15/2015 Connective tissue Multypurposes: binding supporting protecting forming blood storing fats filling space Connective cells are separated by: solid (as in bone), soft (as in loose connective tissue), or liquid (as in blood) non-cellular matrix.
4/15/2015 Major types of connective tissue Loose connective tissue (LCT); Adipose tissue; Fibrous connective tissue (FCT); Cartilage; Bone; Blood
4/15/2015 Major types of connective tissue Loose Connective Tissue (LCT) occurs beneath epithelium in skin and many internal organs, such as lungs, arteries and the urinary bladder. Forms a protective layer over muscle, nerves, and blood vessels and holds organs in place.
4/15/2015 Major types of connective tissue Has all three fiber types: - collagenous (keep the flesh and bones connected) – bundles of fibers containing three collagen molecules each; - elastic – long threads of protein elastin (elastic and flexible); - reticular (joint connective tissue with adjacent).
4/15/2015 Loose Connective Tissue holds organs in place and attaches epithelia to underlying tissues Fibroblasts and macrophages are the main type cells that occur in LCT. Fibroblasts secrete the protein ingredients of the extracellular fibers. Macrophages are amoeboid cells that roam the maze of fibers and the debris of dead cells by phagocytosis.
4/15/2015 Various types of connective tissue Red blood cells; the single neutrophil Bone cells cartilage adipose tissue
4/15/2015 Adipose cells Adipose tissue is a special form LCT and has enlarged fibroblasts storing fats and reduced intracellular matrix. Adipose tissue facilitates energy storage and insulation.
4/15/2015 Fibrous connective tissue Fibrous Connective Tissue (FCT) has many fibers of collagen closely packed together. FCT occurs in tendons, which connect muscle to bone.tendons Ligaments are also composed of FCT and connect bone to bone at a joint.Ligaments
4/15/2015 Cartilage Cartilage is a "rigid" connective tissue which has structural proteins deposited in the matrix between cells. It is composed by collagenous fibers and chondroitin sulfate (secreted by chondrocytes)
4/15/2015 Cartilage Cartilage forms the embryonic skeleton of vertebrates and the adult skeleton of sharks and rays. It also occurs in the human body in the ears, tip of the nose, and at joints.
4/15/2015 Bone Bone is mineralised connective tissue formed by osteoblasts: bone-forming cells that deposit a matrix of collagen and calcium phosphate – hardens into the mineral hydroxyapatite. The combination of hard mineral and flexible collagen makes bone harder than collagen. Bone also serves as a reservoir (or sink) for calcium.
4/15/2015 Bone Two types of bone occur. Dense bone has osteocytes (osteoblasts trapped in their secretions) located in lacunae connected by canaliculi.osteocytes Lacunae are commonly referred to as Haversian canals.Haversian canals Spongy boneSpongy bone occurs at the ends of bones and has bony bars and plates separated by irregular spaces. The solid portions of spongy bone pick up stress.
4/15/2015 Blood Blood is a connective tissue of cells separated by a liquid (plasma) matrix.plasma Contains water, salts, and proteins. The types of cells occur: - red blood cells (erythrocytes) carry oxygen;erythrocytes - white blood cells (leukocytes) function in the immune system;leukocytes - Platelets - cell fragments that function in blood clotting.Platelets
4/15/2015 Blood Blood cells are made in red marrow near the ends of long bones. Plasma transports dissolved glucose, wastes, carbon dioxide and hormones, as well as regulating the water balance for the blood cells.
4/15/2015 Human Red Blood Cells, Platelets and T-lymphocyte (SEM x 9,900). This image is copyright of Dennis Kunkel
4/15/2015 Nervous system Nervous tissueNervous tissue functions in the integration of stimulus and control of response to that stimulus. Nerve cells are called neurons.neurons Each neuron has a cell body, an axon, and many dendrites.axondendrites Nervous tissue is composed of two main cell types: neurons and glial cells. Neurons transmit nerve messages. Glial cells are in direct contact with neurons and often surround them.
4/15/2015 Nervous system The neuron is the functional unit of the nervous system.neuron Humans have about 100 billion neurons in their brain alone! While variable in size and shape, all neurons have three parts. DendritesDendrites receive information from another cell and transmit the message to the cell body. The cell body contains the nucleus, mitochondria and other organelles typical of eukaryotic cells.cell body The axon conducts messages away from the cell body.axon
4/15/2015 Nervous system large multipolar neuron
4/15/2015 Pyramidal Neurons from the Central Nervous System (SEM x3,960).
4/15/2015 Muscle tissue consists of cells capable of contraction Muscle tissueMuscle tissue facilitates movement of the animal by contraction of individual muscle cells (referred to as muscle fibers). muscle fibers Three types of muscle fibers occur in animals (the only taxonomic kingdom to have muscle cells):kingdom skeletal (striated) smooth cardiac
4/15/2015 Muscle tissue Muscle fibers are multinucleated, with the nuclei located just under the plasma membrane. Most of the cell is occupied by striated, thread-like myofibrils.myofibrils Within each myofibril there are dense Z lines.Z lines
4/15/2015 Muscle tissue A sarcomere (or muscle functional unit) extends from Z line to Z line. Each sarcomere has thick and thin filaments.sarcomere The thick filaments are made of myosin and occupy the center of each sarcomere.myosin Thin filaments are made of actin and anchor to the Z line.actin
4/15/2015 Skeletal muscle Skeletal (striated) muscleSkeletal (striated) muscle fibers have alternating bands perpendicular to the long axis of the cell. These cells function in conjunction with the skeletal system for voluntary muscle movements.skeletal system The bands are areas of actin and myosin deposition in the cells.actinmyosin
4/15/2015 Smooth muscle Smooth muscle fibers lack the banding, although actin and myosin still occur. These cells function in involuntary movements and/or autonomic responses (such as breathing, secretion, ejaculation, birth, and certain reflexes). autonomic Smooth muscle fibers are spindle shaped cells that form masses. These fibers are components of structures in the digestive system, reproductive tract, and blood vessels.digestive system
4/15/2015 Cardiac muscle Cardiac muscle fibers are a type of striated muscle found only in the heart. The cell has a bifurcated (or forked) shape, usually with the nucleus near the center of the cell. The cells are usually connected to each other by intercalated disks.
4/15/2015 Animal cell cell membrane mitochondrion Golgi complex lysosome smooth ER rough ER nucleus
4/15/2015 Plant versus animal cell Plants have three tissue types: ground, dermal, and vascular. Animals have four: epithelial, connective, muscle, and nervous. In general, plant cells differ from animal cells in that the membrane is surrounded by a cell wall made of cellulose. They also have larger vacuoles (fluid - filled pouches), and contain chloroplasts that convert light energy to chemical energy for the synthesis of glucose.