IBDP Biology Chapter 12 Notes

neurobiology and behaviour


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The material made available on Tychr’s website is available for all IBDP subjects and is specially curated after an extensive amount of effort to ensure that the notes are in consonance with the IB curriculum and are an amalgamation from various textbooks prescribed by the IBO.Students often face a challenge understanding concepts, especially concepts that are new and tricky. These IB Biology Notes will help the student cover the chapter of Cell Biology entirely while explaining each and every concept in a detailed and easy way.

This unit deals with the formation of the neural tube and the brain and how the senses respond to stimuli. Neurobiology is the stream of science that deals with the study of the complex information processing system that includes the brain and the nervous system. Neural development begins with the formation of a neural tube which will give rise to the brain and the spinal cord. Neurogenesis is the formation of neurons by differentiation of neuroblast. Then we move on to plasticity, which refers to the brain’s ability to adapt and reform accordingly. Brain develops from the anterior end of the neural tube.

The brain and spinal cord are a part of CNS(central), whereas ANS(autonomic), ES(enteric) and SNS(somatic) are parts of PNS. ANS has two subdivisions sympathetic (flight or fight) and parasympathetic(rest and relax). Then we discuss brain death when the movements, respiration and reflexes are absent, EEG is flat, and CBF shows no activity. Heartbeat and spinal reflexes may persist because they are not entirely under brain control. The cerebral cortex is the largest part of the mature brain made up of a lot of gyri and sulci.

Alternatively, we also talk about the types of receptors(mechano, Thermo, chemo, photo), eye and ear. Animals have both innate and learned behaviours (learnt by imprinting, conditioning and learning). In the end, we discuss neuropharmacology, the neurotransmitters involved and the drugs that modulate them. We also discuss ethology, i.e. the study of animal behaviour briefly.