BIO MOD 2 YR 11

• Types of organisms


  • Unicellular
  • Colonial
  • Multicellular
• Unicellular organism


  • A single cell that performs all functions necessary for survival
  • Prokaryotic or eukaryotic
  • E.g. Escherichia coli (a bacterium) or Amoeba (a protozoan)
• Colonial organism


  • A collection of single-celled organisms that live together in a colony
  • Exhibits characteristics of both unicellular and multicellular organisms; all individuals in the colony are capable of carrying out functions necessary for survival, some contain cells that have specialised functions which coordinate with other cells in the colony
  • E.g. Volvox (a colonial alga), coral and jellyfish
• Multicellular organism


  • Multiple cells that are specialised to perform specific functions within the organism, contributing to a division of labour
  • More complex and have a higher level of organisation
  • Cells in multicellular organisms form tissues, organs, and organ systems
  • E.g. plants, animals, fungi
• Cell Specialisation & Function

  1. Cells become specialised to carry out a specific function

  2. Differentiation: the process by which a cell develops specific structures and characteristics, which enable it to perform a unique function

  3. They possess the necessary organelles, shape, and other features
• Cell types and their structure and function

  • Red Blood Cell
  • Muscle Cell
  • Neuron/Nerve cell
  • White Blood Cell
  • Sperm Cell
• Plant cell types and their structure and function

  • Meristematic
  • Dermal
  • Vascular
  • Ground
• CELLS = smallest unit of living matter; the basic building block of all living things
• TISSUE = single cells don't work alone, a group of cells of the same type work together to perform a specific task
• ORGAN = A structure containing a group of different tissues that carry out a specific function
• ORGAN SYSTEM = a group of organs working together to carry out a specific life function
• ORGANISM = a living thing that has an organised structure and its made up of several systems. The systems work together in order for life processes, such as breathing and digestion, can be carried out, keeping multicellular organism alive
• Cell Organisation, Specialistion, Function: Specialised cells make up tissues, with different types of tissues forming organs that carry out particular functions within an organ system
• Each general type of tissue further contains many different functional types based on these specialised cells that comprise them
• Animal tissues


  • Epithelial
  • Connective
  • Nervous
  • Muscular
• Epithelial tissue


  Barrier for protection of organs, secretion of hormones, absorption, forms glands
• Connective tissue


  Attaches organs and tissues together<|>Stores fat<|>Helps move nutrients and other substances between tissues and organs<|>Helps repair damaged tissue
• Nervous tissue


  Coordinating and controlling body activities<|>Role in emotions/memory
• Muscular tissue


  Applies forces to different parts of the body by contraction<|>Controls movement of organism
• Plant tissues


  • Meristematic
  • Dermal
  • Vascular
  • Ground
• Meristematic tissue


  Cells in the tissue DIVIDE to produce new growth for wounds
• Dermal tissue


  Protects the plant tissue<|>Controls water absorption
• Vascular tissue


  Vessels that transport nutrients around the plant<|>Xylem (transports water)<|>Phloem (transports nutrients)
• Ground tissue


  Food storage, support and photosynthesis
• Hierarchical organisation of cells enables the efficient functioning of multicellular organisms
• Cell differentiation and specialisation produce cells with specific functions that are then grouped together as tissues, organs and systems
• Interaction and cooperation between cells, tissues, organs and systems provide multicellular organisms with abilities that are beyond limitations of single cells
• Autotrophs


  Organisms that can produce their own food (self feeders)<|>Use photosynthesis to convert light into chemical energy to produce organic molecules (glucose)<|>E.g. Plants, algae, some bacteria
• Plant parts and their functions

  • Roots
  • Leaves
  • Stem
  • Flower
• Roots


  Long and thin shape, root hairs increase SA:V ratio<|>Located underground<|>Endodermis regulates the passage of water and nutrients into the vascular tissues<|>Root cap helps the root penetrate the soil by reducing friction and protecting delicate cells<|>Roots absorb water from the soil and helps to hold the plant in place
• Leaves


  Leaf veins provides support, transports water and nutrients (sugars)<|>Leaf epidermis provides protection and regulates gas exchange<|>Photosynthesis occurs in chlorophyll<|>Leaves use sunlight to provide the plant with energy
• Stem


  Stem epidermis serves as a protective barrier against physical damage, pathogens and excessive water loss<|>Vascular bundles contain xylem and phloem tissues<|>The stem helps to support the plant
• Flower


  Peduncle: stalk-like structure that supports the flower<|>Petals serve to attract pollinators<|>Ovary: swollen base of the carpel where ovules are produced and fertilisation occurs<|>Flower helps the plant to reproduce and produce seeds
• Flower parts


  • Carpel
  • Stigma
  • Style
  • Ovary
  • Stamen
  • Anther
  • Filament
  • Pollen
• Carpel


  Ovary - site of fertilisation; sperm cells from pollen grains + egg cells (ovules) = zygotes<|>Style - provides a pathway for pollen tubes to grow and deliver sperm cells to the ovules<|>Stigma - capture and recognize pollen grains, promote the germination of pollen tubes and the transfer of sperm cells to the ovules<|>Produces ovules containing eggs, protects them, and facilitates fertilisation by receiving pollen. It nurtures the developing seeds within ovaries, vital for plant reproduction
• Stigma


  Papillae: small, finger-like projections that increase SA:V ratio<|>Stigma secretion traps pollen grains upon contact<|>Coloration - bright colours serve as visual cues to pollinators, guiding them towards the reproductive structures of the plant<|>Capture and recognize pollen grains, promoting the germination of pollen tubes and the transfer of sperm cells to the ovules
• Style


  Papillae are small, finger-like projections that increase the surface area to volume ratio<|>Elongated structure acts as a channel<|>Provides a pathway for pollen tubes to grow and deliver sperm cells to the ovules for fertilisation
• Ovary


  Funicles provide support and facilitate nutrient transfer to the developing ovules<|>Ovary wall protects developing ovules and seeds<|>Site of fertilisation, where sperm cells from pollen grains unite with egg cells (ovules) to form zygotes
• Stamen


  Anther - bilobed structure contains pollen sacs<|>Filament - the slender stalk that provides structural support and flexibility<|>Pollen - sacs contain microspore mother cells that undergo meiosis to produce pollen grains<|>The stamen is the male reproductive organ in flowering plants that is essential for the reproduction of plants
• Anther


  Lobes that contain the pollen sacs<|>Epidermis: protective layer<|>Fibrous layer is a layer of cells that provide mechanical support<|>Bilobed structure containing pollen sacs and is highly specialised for the production, protection and release of pollen grains