PLANT CELL. Department of Biology, College of Science, Polytechnic University of the Philippines 2

Transcription

1 PLANT CELL Jhia Anjela D. Rivera 1,2 1 Department of Biology, College of Science, Polytechnic University of the Philippines 2 Department of Biological Sciences, School of Science and Technology, Centro Escolar University

2 OBJECTIVES Identify the different parts of a plant cell; Describe the structure of the organelles and; Illustrated the generalized structure of a typical plant cell.

3 OUTLINE Cell Cell Organelles

4 PLANT CELL Basic unit of structure and function in a plant Eukaryotic cells Has many structures that are the same with an animal cell Main Structures Nucleus Protoplasm (Cytoplasm)

5 PLANT CELL AND ITS COMPONENTS Protoplasm (Cytoplasm) Cell Wall Middle Lamella Plasma Membrane Endoplasmic Reticulum Ribosomes Mitochondria Plastids Golgi bodies or Dictyosomes Microtubules Membranes Nucleus Inclusions Vacuoles

6 PROTOPLASM Living contents of a cell that is surrounded by a plasma membrane An accumulation of water, sugar cellulose, hormones, organic and inorganic compounds General term for cytoplasm

7 CELL WALL Outermost part of the plant cell Provides the cells with structural support and protection Non-living material made up of cellulose and other substances like lignin, suberin and cutin Lignin - integral part of the secondary cell walls of plants; organic substance binding the cells, fibres and vessels which constitute wood and the lignified elements of plants Suberin - highly hydrophobic and a somewhat 'rubbery' material and waxy substance found in higher plants, prevent water from penetrating the tissue Cutin - one of two waxy polymers that are the main components of the plant cuticle, which covers all aerial surfaces of plants

8 MIDDLE LAMELLA Non-living cementing intracellular layer A pectin layer which cements the cell walls of two adjoining cells together Provides the cells with stability so they can form plasmodesmata Plasmodesmata - microscopic channels which traverse the cell walls of plant cells, enabling transport and communication between them

9 PLASMA MEMBRANE Also known as plasmalemma or cell membrane Made up of phospholipids and proteins Selectively permeable membrane Regulates the entrance and exit of substances in a cell

10 ENDOPLASMIC RETICULUM Facilitates transport of material within the cell Provides a surface area for the synthesis of many important compounds within the cell Rough ER ribosomes are attached to the ER, site of active protein synthesis Smooth ER does not contain ribosomes, synthesis and transport of lipids Associated with plasmodesmata and cytoplasmic connections from cell to cell across cell walls (for cell communication purposes)

11 RIBOSOMES Dense granules involved in protein synthesis

12 MITOCHONDRIA Double walled membranous sacs with folded inner partitions called cristae Releases energy from food molecules and transform energy into usable ATP which happens during cellular respiration

13 PLASTIDS Rounded, oval or irregularly shaped protoplasmic bodies Types Chloroplasts contain chlorophyll (green) and carotenoid pigments (orange-yellow) needed for photosynthesis Leucoplasts or colorless plastids some are involved in the storage of starch, referred to as amyloplasts elaioplast (starch) aleuroplasts (air storage of proteins) Chromoplasts red and yellow pigments called carotenoids

14 GOLGI BODIES OR DICTYOSOMES Circular, flattened vesicles of cisternae arranged in stacks Cisternae - carry Golgi enzymes to help or to modify cargo proteins traveling through them destined for other parts of the cell Serves as packaging areas for secretions

15 MICROTUBULES Tubular, fibrillar structures of indefinite length with cylindrical walls of highly organized globular protein (tubulin) Microtubules can transform into cilia and flagella for movement and spindle fibers involved in cell division

16 MEMBRANES Bind the organelles Plasmalemma, nuclear membrane etc

17 NUCLEUS Structure: separated by a porous nuclear membrane within thecytoplasm, sphere shaped, contains the nucleolus Function: -control center of the cells -storage center of cells DNA Nucleolus aggregate of granules madeof ribonucleic acid (RNA)

18 NUCLEUS Structure: separated by a porous nuclear membrane within thecytoplasm, sphere shaped, contains the nucleolus Function: -control center of the cells -storage center of cells DNA Nucleolus aggregate of granules madeof ribonucleic acid (RNA)

19 VACUOLES A membrane-bound organelle enclosed compartments which are filled with water containing inorganic and organic molecules including enzymes in solution, though in certain cases they may contain solids which have been engulfed

20 NOW, WORK WITH YOUR GROUPS FOLLOW THE PROCEDURE IN YOUR LABMANUAL. NOTE: YOU WILL WORK AS A GROUP, BUT YOU WILL DO THE ACTIVITY INDIVIDUALLY. I WILL BE CHECKING YOUR OUTPUTS ONE BY ONE. BE CAREFUL WITH THE SCALPEL. IF YOU DON T HAVE A SCALPEL THEN A BLADE WILL DO.