1 / 14

AP Biology

Learn how nervous systems evolved, from nerve nets to complex structures like brains and nerve cords, enabling reception, integration, and motor output of stimuli in animals.

rluna
Download Presentation

AP Biology

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. AP Biology Nervous Systems Part 1

  2. Step 1: Reception

  3. Step 2: Transduction

  4. Step 3: Response

  5. –92 mV +62 mV Inner chamber Outer chamber Inner chamber Outer chamber 150 mM NaCl 150 mM KCl 15 mM NaCl 5 mM KCl Ions and Energy Cl– K+ Na+ Cl– Sodium channel Potassium channel Artificial membrane

  6. Evolution of a Nervous System • Everything starts with the evolution of an organism-wide nerve net in Cnidarians  helps to control movement. • Then, evolution of a “brain” helps lead to greater control  utilization of a nerve cord to span the whole body. • Cephalization through the evolution of a “head region” allows for reception and response to many different stimuli.

  7. Evolution of a Nervous system in Animals

  8. Overview of the Nervous System • Sensory Input: sending information into the brain or spinal cord. • Sensory receptors found within the body receive a stimulus from outside environment. • A stimulus is a form of energy such as light, chemicals, pressure or sound waves.

  9. Overview of the Nervous System • 2. Integration: this is the interpretation of the energy by the CNS. • This interpretation of the stimulus leads to a determination of what the appropriate response will be.

  10. Overview of the Nervous System • 3. Motor Output: sending out impulses from the brain and spinal cord to glands or muscles to create a response. • This response is carried out by effector cells – these structures can have an effect on the body.

  11. CNS vs. PNS • Central Nervous System (CNS) • - This includes the brain and spinal cord. • This part of the nervous system does the overall “thinking” about stimuli that the body receives. • Peripheral Nervous System (PNS) • This includes all sensory receptors and motor nerves that spread out throughout the body. • This part of the nervous system carries out the response to stimuli.

  12. Neuron structure Neuron Structure: cell body, dendrites, axon, myelin sheath, synaptic terminal, synapse, neurotransmitters, presynaptic cell, postsynaptic cell

  13. Synapse and Neurotransmitter Nerve signals must move through local communication (synaptic communication). This means that each neuron does not physically touch the next. All signals must transition between electrical and chemical messages. This all takes place at the synapse!

  14. Schwann Cells OR Oligiodendrocytes Nodes of Ranvier Layers of myelin Axon Schwann cell Schwann cell Nucleus of Schwann cell Nodes of Ranvier Axon Myelin sheath 0.1 µm

More Related