Simple IB Biology

Simple IB Biology

By Amirali GhajariScienceLife Sciences
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Simple IB Biology episodes

  • #1.5 Cell theory - The origin of cells

    In this sub-unit of IB biology, we are going to explain the shortest part of unit 1, we are going to understand the concepts of:

    • Cells can only be formed by division of pre-existing cells
    • The first cells must have arisen from non-living material
    • The origin of eukaryotic cells can be explained by the endosymbiotic theory
      • 5 min
    • #1.4 Cell Theory - Membrane Transport

      In today's podcast we are going to explore and understand the concepts of:

      • Particles move across membranes by simple diffusion, facilitated diffusion, osmosis and active transport
      • The fluidity of membranes allows materials to be taken into cells by endocytosis or released by exocytosis
      • Vesicles move materials within cells
        • 13 min
      • #1.3 Cell Theory - Membrane Structure

        In this sub-unit we are going to explore the concepts and understanding of:

        Understandings:

        • Phospholipids form bilayers in water due to the amphipathic properties of phospholipid molecules
        • Membrane proteins are diverse in terms of structure, position in the membrane and function
        • Cholesterol is a component of animal cell membranes


          • 9 min
        • #1.2 Cell Biology - Ultrastructure of cells

          In this second part of unit 1 of the IB biology, we will explore the concepts of:

          • Prokaryotes have a simple cell structure without compartmentalization
          • Eukaryotes have a compartmentalized cell structure
          • Electron microscopes have a much higher resolution than light microscopes


            • 11 min
          • #1.1 Cell Biology - Introduction to cell theory

            Welcome everyone in the first episode of this podcast we are going to understand the key concepts of the first part of IB biology which are:

            • According to the cell theory, living organisms are composed of cells
            • Organisms consisting of only one cell carry out all the functions of life in that cell
            • Surface area to volume ratio is important in the limitation of cell size
            • Multicellular organisms have properties that emerge from the interaction of their cellular components
            • Specialized tissues can develop by cell differentiation in multicellular organisms
              • 10 min
            • #6.6 Human Physiology - Hormones, Homeostasis, and Reproduction

              In the last sub-unit of unit 6 we are going to explore the content of:

              • Insulin and glucagon are secreted by β and α cells of the pancreas respectively to control blood glucose concentration
              • Thyroxin is secreted by the thyroid gland to regulate the metabolic rate and help control body temperature
              • Leptin is secreted by cells in adipose tissue and act on the hypothalamus of the brain to inhibit appetite
              • Melatonin is secreted by the pineal gland to control circadian rhythms
              • A gene on the Y chromosome causes embryonic gonads to develop as testes and secrete testosterone
                • 25 min
              • #6.5 Human Physiology - Neurons and Synapses

                In this sub-unit of unit 6, we are ging to synthesize and explain the contents such as:

                • Neurons transmit electrical impulses
                • The myelination of nerve fibers allows for saltatory conduction
                • Neurons pump sodium and potassium ions across their membranes to generate a resting potential
                • An action potential consists of depolarization and repolarization of the neuron
                • Nerve impulses are action potentials propagated along the axons of neurons
                  • 20 min
                • #6.4 Human Physiology - Gas Exchange

                  In this sub-unit we are going to explore the contents of:

                  Understandings:

                  • Ventilation maintains concentration gradients of oxygen and carbon dioxide between air in alveoli and blood flowing in adjacent capillaries
                  • Air is carried to the lungs in the trachea and bronchi and then to the alveoli in bronchioles
                  • Type I pneumocytes are extremely thin alveolar cells that are adapted to carry out gas exchange
                  • Type II pneumocytes secrete a solution containing surfactant that creates a moist surface inside the alveoli to prevent the sides of the alveolus adhering to each other by reducing surface tension
                    • 18 min
                  • #6.3 Human Physiology - Immune defense

                    In this sub-unit we are going to explore contents of:

                    • The skin and mucous membranes form a primary defence against pathogens that cause infectious disease
                    • Cuts in the skin are sealed by blood clotting
                    • Clotting factors are released from platelets
                    • The cascade results in the rapid conversion of fibrinogen to fibrin by thrombin
                      • 16 min
                    • #6.2 Human Physiology - Blood System

                      In this sub-unit of human physiology we will explore contents of:


                      • Arteries convey blood at high pressure from the ventricles to the tissues of the body
                      • Arteries have muscle cells and elastic fibres in their walls
                      • The muscle and elastic fibres assist in maintaining blood pressure between pump cycles
                      • Blood flows through tissues in capillaries
                      • Capillaries have permeable walls that allow exchange of material between cells in the tissue and the blood in the capillary
                      • Veins collect blood at low pressure from the tissues of the body and return it to the atria of the heart
                      • Valves in veins and the heart ensure circulation of blood by preventing backflow
                        • 22 min

                      About Simple IB Biology

                      From the publisher's feed

                      As an IB biology HL student, I decided to record a podcast for biology in order to record myself first and understand better, then upload this so everyone else who would like to understand biology in…