biologypod https://biologypod.podbean.com VCE year 11 Biology Sun, 22 Mar 2009 17:29:00 -0500 https://podbean.com/?v=5.5 en Copyright 2012 simon cohen. All rights reserved. Education 1440 No false https://pbcdn1.podbean.com/imglogo/image-logo/126732/BiologyPod.jpg biologypod https://biologypod.podbean.com 144 144 Taxonomy, Classification & Species Taxonomy, Classification & Species https://biologypod.podbean.com/e/taxonomy-classification-species/ https://biologypod.podbean.com/e/taxonomy-classification-species/#comments Sun, 22 Mar 2009 17:29:00 -0500 http://biologypod.podbean.com/e/taxonomy-classification-species/ BiologyPod@gmail.com   As an example let's consider the Linnaean classification for modern humans:-
  • Domain: Eukarya (organisms which have cells with a membrane bound nucleus)
  • Kingdom: Animalia(mobile heterotrophs made from eukaryotic cells having cell membrane but lacking cell wall.)
  • Phylum: Chordata (animals with a notochord (a dorsal nerve cord ) - Subphylum: Vertebrata (having a back bone)
  • Class: Mammalia (Warm Blooded (endothermic) vertebrates with hair and mammary glands to secrete milk for their young) -  Cohort: Placentalia(possessing a placental to enable them to give birth to live young after a full internal gestation)
  • Order: Primates (collar bone, eyes face forward, grasping hands with fingers) -  Suborder: Anthropoidea(monkeys & apes as opposed to the lemurs & lorises)
  • Family: Hominidae (great apes)
  • Genus: Homo (humans and related extinct species)
  • Species: Homo sapiens
]]> Taxonomy, Classification & Species” - BiologyPod Episode 4 2009 brought to you by Simon Cohen – email me your feedback or questions BiologyPod@gmail.com   As an example let's consider the Linnaean classification for modern humans:-
  • Domain: Eukarya (organisms which have cells with a membrane bound nucleus)
  • Kingdom: Animalia(mobile heterotrophs made from eukaryotic cells having cell membrane but lacking cell wall.)
  • Phylum: Chordata (animals with a notochord (a dorsal nerve cord ) - Subphylum: Vertebrata (having a back bone)
  • Class: Mammalia (Warm Blooded (endothermic) vertebrates with hair and mammary glands to secrete milk for their young) -  Cohort: Placentalia(possessing a placental to enable them to give birth to live young after a full internal gestation)
  • Order: Primates (collar bone, eyes face forward, grasping hands with fingers) -  Suborder: Anthropoidea(monkeys & apes as opposed to the lemurs & lorises)
  • Family: Hominidae (great apes)
  • Genus: Homo (humans and related extinct species)
  • Species: Homo sapiens
]]> false No 965 Life Molecules Life Molecules https://biologypod.podbean.com/e/life-molecules/ https://biologypod.podbean.com/e/life-molecules/#comments Sun, 01 Mar 2009 22:48:18 -0500 http://biologypod.podbean.com/e/life-molecules/ BiologyPod@gmail.com To download this podcast just follow the link to http://biologypod.podomatic.com/ or http://biologypod.podbean.com/   In this Podcast I look at the areas of what is life and what molecules are associated with living things. ]]> Life Molecules” - BiologyPod Episode 3 2009 brought to you by Simon Cohen – email me your feedback or questions BiologyPod@gmail.com To download this podcast just follow the link to http://biologypod.podomatic.com/ or http://biologypod.podbean.com/   In this Podcast I look at the areas of what is life and what molecules are associated with living things. ]]> false No 1152 Membranes Membranes https://biologypod.podbean.com/e/membranes/ https://biologypod.podbean.com/e/membranes/#comments Sun, 01 Mar 2009 22:43:16 -0500 http://biologypod.podbean.com/e/membranes/ BiologyPod@gmail.com To download this podcast just follow the link to http://biologypod.podomatic.com/ or http://biologypod.podbean.com/   In this Podcast I look at the areas of cell membranes and membrane permeability.  Membrane Construction  • Cell membranes consist of a double layer (bilayer) of phospholipid molecules (fatty molecules) and also contain protein molecules of various sizes,carbohydrates and cholesterol. • In eukaryote cells, membranes include the plasma membrane, which encloses the cytoplasm, and an interconnected network of non-plasma membranes. • Membranes have many functions in cells, including controlling the passage of molecules into and out of the cell, establishing compartments within cells (organelles), & carrying receptors for recognition and communication.   Membrane Permeability Permeability describes the degree to which substances can pass through a cell’s membrane. Cell membranes are semipermeable, ( only some molecules can pass through.) Because cell membranes are semipermeable, a concentration gradient exists such that some substances are present on one side of the membrane in higher concentrations than on the other side. Passive transport is movement down the concentration gradient. No energy is expended in this activity. Substances can be passively transported via diffusion, facilitated diffusion, or osmosis. Diffusion: Particles move spontaneously from an area of higher concentration to an area of lower concentration. Diffusion usually refers to small, uncharged particles, such as oxygen, carbon dioxide, and some ions but some larger lipid soluble molecules such as other lipids (eg steroids) or alcohol can also diffuse through a membrane. Facilitated diffusion: Particles move spontaneously across the cell membrane from an area of higher concentration to an area of lower concentration with the help of special transport proteins. Facilitated diffusion permits the passage of both large and charged molecules (eg glucose) through the cell membrane. Osmosis: Osmosis is the diffusion of water  from an area of higher water concentration (low solute concentration - Hypotonic) to an area of lower water concentration (high solute concentration - Hypertonic.) The tonicity, or relative solute concentration, of a cell determines the direction in which osmosis occurs:        Hypertonic: higher solute concentration        Isotonic: equal solute concentration        Hypotonic: lower solute concentration   Active transport is movement up the concentration gradient. This activity is powered by the cell’s energy. The cell expends energy (from ATP) and is enabled through the use of carrier proteins, which bind to a substance and shuttle it through pores in the cell membrane. Carrier proteins can perform two methods of active transport: Endocytosis occurs when proteins bring substances into the cell through the vacuoles or vesicles. Consumption of solid matter, such as cholesterol, through endocytosis is called phagocytosis. Consumption of extracellular liquid matter is called pinocytosis. Exocytosis occurs when carrier proteins remove substances from the cell through the vacuoles or vesicles. Insulin is delivered from the cell to the bloodstream by exocytosis.  ]]> Membranes” - BiologyPod Episode 2 2009 brought to you by Simon Cohen – email me your feedback or questions BiologyPod@gmail.com To download this podcast just follow the link to http://biologypod.podomatic.com/ or http://biologypod.podbean.com/   In this Podcast I look at the areas of cell membranes and membrane permeability.  Membrane Construction  • Cell membranes consist of a double layer (bilayer) of phospholipid molecules (fatty molecules) and also contain protein molecules of various sizes,carbohydrates and cholesterol. • In eukaryote cells, membranes include the plasma membrane, which encloses the cytoplasm, and an interconnected network of non-plasma membranes. • Membranes have many functions in cells, including controlling the passage of molecules into and out of the cell, establishing compartments within cells (organelles), & carrying receptors for recognition and communication.   Membrane Permeability Permeability describes the degree to which substances can pass through a cell’s membrane. Cell membranes are semipermeable, ( only some molecules can pass through.) Because cell membranes are semipermeable, a concentration gradient exists such that some substances are present on one side of the membrane in higher concentrations than on the other side. Passive transport is movement down the concentration gradient. No energy is expended in this activity. Substances can be passively transported via diffusion, facilitated diffusion, or osmosis. Diffusion: Particles move spontaneously from an area of higher concentration to an area of lower concentration. Diffusion usually refers to small, uncharged particles, such as oxygen, carbon dioxide, and some ions but some larger lipid soluble molecules such as other lipids (eg steroids) or alcohol can also diffuse through a membrane. Facilitated diffusion: Particles move spontaneously across the cell membrane from an area of higher concentration to an area of lower concentration with the help of special transport proteins. Facilitated diffusion permits the passage of both large and charged molecules (eg glucose) through the cell membrane. Osmosis: Osmosis is the diffusion of water  from an area of higher water concentration (low solute concentration - Hypotonic) to an area of lower water concentration (high solute concentration - Hypertonic.) The tonicity, or relative solute concentration, of a cell determines the direction in which osmosis occurs:        Hypertonic: higher solute concentration        Isotonic: equal solute concentration        Hypotonic: lower solute concentration   Active transport is movement up the concentration gradient. This activity is powered by the cell’s energy. The cell expends energy (from ATP) and is enabled through the use of carrier proteins, which bind to a substance and shuttle it through pores in the cell membrane. Carrier proteins can perform two methods of active transport: Endocytosis occurs when proteins bring substances into the cell through the vacuoles or vesicles. Consumption of solid matter, such as cholesterol, through endocytosis is called phagocytosis. Consumption of extracellular liquid matter is called pinocytosis. Exocytosis occurs when carrier proteins remove substances from the cell through the vacuoles or vesicles. Insulin is delivered from the cell to the bloodstream by exocytosis.  ]]> false No 1442 Organelles Organelles https://biologypod.podbean.com/e/organelles/ https://biologypod.podbean.com/e/organelles/#comments Mon, 23 Feb 2009 01:03:24 -0500 http://biologypod.podbean.com/e/organelles/ BiologyPod@gmail.com   In this Podcast we will be looking at cell theory, different types of organisms and organelles within cells.   Cell Theory  
  1. all living organisms are composed of cells (and the products of cells)
  2. all cells come from other cells
  3. the cell is the smallest organisational unit of living things
  Different Organisms   Prokaryote e.g. Bacteria may have a cell wall (or capsule) but no organelles, some contain chlorophyll (cyanobacteria) DNA Circular. Eukaryotic Protista e.g. Algae and Amoeba – mostly single celled organisms, some have cell wall, some contain chloroplasts. Eukaryote Fungi – like plants but non-cellulose cell wall and no chloroplasts Eukaryote Plants – Cellulose cell wall, chloroplasts and large central vacuole Eukaryote Animal – No cell wall, no chloroplasts small vacules.    Organelles   Cell membrane: (also called the plasma membrane) a fluid bilayer of phospholipid molecules enclosing the cytoplasm in all cells. It controls the movement of material into and out of the cell and communication between cells. Chloroplast: found in some cells of plant and some protests,; a green organelle (due to chlorophyll) where photosynthesis takes place. It is composed of a membrane folded into many layers called grana. Cytoplasm: the contents of a cell, other than the nucleus. Mostly water it also contains ions, salts, enzymes, food molecules and organelles (other than the nucleus.) Cytosol: the fluid, watery, component of cytoplasm between organelles. Endoplasmic reticulum: a network of intracellular membranes that links with the nuclear membrane. Endoplasmic reticulum may be rough (associated with ribosomes) or smooth (lacking ribosomes). It is involved with the production, processing, transport and storage of materials within the cell. Golgi apparatus: a stack of flat membrane sacs where the final synthesis and packaging of proteins into vesicles occurs before they are secreted from the cell. It is closely associated with the endoplasmic reticulum. Lysosomes: membrane-bound vesicles containing enzymes that break down waste materia. Mitochondria: organelles composed of many folded layers of membrane. Mitochondria are involved respiration, the energy transformations that release energy for use by the cell. Nucleus: a large organelle that contains genetic material (chromosomes composed of DNA and proteins) and controls cellular activities. It is surrounded by a double-layered nuclear membrane, containing pores that communicate with the cytoplasm Ribosomes: tiny organelles located in the cytosol, sometimes associated with endoplasmic reticulum. They are sites of production of proteins. Vacuole: a membrane-bound, liquid-filled space found in most cells. Plant cells typically have large fluid-filled vacuoles, containing cell sap, that provide both physical support through turgidity and storage. In other cells, vacuoles may be involved in intracellular digestion (food vacuoles) or water balance (contractile vacuoles). Vesicles: membrane-bound organelles often associated with transport in cell.]]> BiologyPod@gmail.com   In this Podcast we will be looking at cell theory, different types of organisms and organelles within cells.   Cell Theory  
  1. all living organisms are composed of cells (and the products of cells)
  2. all cells come from other cells
  3. the cell is the smallest organisational unit of living things
  Different Organisms   Prokaryote e.g. Bacteria may have a cell wall (or capsule) but no organelles, some contain chlorophyll (cyanobacteria) DNA Circular. Eukaryotic Protista e.g. Algae and Amoeba – mostly single celled organisms, some have cell wall, some contain chloroplasts. Eukaryote Fungi – like plants but non-cellulose cell wall and no chloroplasts Eukaryote Plants – Cellulose cell wall, chloroplasts and large central vacuole Eukaryote Animal – No cell wall, no chloroplasts small vacules.    Organelles   Cell membrane: (also called the plasma membrane) a fluid bilayer of phospholipid molecules enclosing the cytoplasm in all cells. It controls the movement of material into and out of the cell and communication between cells. Chloroplast: found in some cells of plant and some protests,; a green organelle (due to chlorophyll) where photosynthesis takes place. It is composed of a membrane folded into many layers called grana. Cytoplasm: the contents of a cell, other than the nucleus. Mostly water it also contains ions, salts, enzymes, food molecules and organelles (other than the nucleus.) Cytosol: the fluid, watery, component of cytoplasm between organelles. Endoplasmic reticulum: a network of intracellular membranes that links with the nuclear membrane. Endoplasmic reticulum may be rough (associated with ribosomes) or smooth (lacking ribosomes). It is involved with the production, processing, transport and storage of materials within the cell. Golgi apparatus: a stack of flat membrane sacs where the final synthesis and packaging of proteins into vesicles occurs before they are secreted from the cell. It is closely associated with the endoplasmic reticulum. Lysosomes: membrane-bound vesicles containing enzymes that break down waste materia. Mitochondria: organelles composed of many folded layers of membrane. Mitochondria are involved respiration, the energy transformations that release energy for use by the cell. Nucleus: a large organelle that contains genetic material (chromosomes composed of DNA and proteins) and controls cellular activities. It is surrounded by a double-layered nuclear membrane, containing pores that communicate with the cytoplasm Ribosomes: tiny organelles located in the cytosol, sometimes associated with endoplasmic reticulum. They are sites of production of proteins. Vacuole: a membrane-bound, liquid-filled space found in most cells. Plant cells typically have large fluid-filled vacuoles, containing cell sap, that provide both physical support through turgidity and storage. In other cells, vacuoles may be involved in intracellular digestion (food vacuoles) or water balance (contractile vacuoles). Vesicles: membrane-bound organelles often associated with transport in cell.]]> false No 1145