CBNS 121 Final Exam Questions and Answers Latest Update 2025

CBNS 121 Final Exam Questions and Answers Latest Update 2025 What is the function of the axon? - Answers it conducts signals and forms synapses with targets What is the function of the dendrite? - Answers receives information from other neurons What is the pre-neuron called? - Answers neurite What happens when you cut an axon? - Answers it allows ONE dendrite to become a new axon What are two things that help the axon find the correct target? - Answers Environmental cues guidepost cells What are the two long range cues mentioned in class? - Answers netrins and semaphorins What are the two short range cues mentioned in class? - Answers cadherins and ephrins What is the growth cone? - Answers the leading edge of the axon Why do neurons die? - Answers neurons are overgenerated during development and so programmed cell death acts as a control over neuronal number What are some of the reasons why a neuron may die? - Answers remove non functioning cells remove cells that with inappropriate connections systems matching remove guidance cues remove transiently important cells remove harmful cells evolutionary change What are the two types of neuronal death? - Answers necrosis programmed cell death Why does necrosis occur? - Answers the cell has become injured pyknosis - Answers condensation of nuclear material that occurs during necrosis What type of cell death occurs during a stroke? - Answers necrosis: hemorrhagic and ischemic Excitotoxicity (why too much glutamate is bad) - Answers the NMDA and AMPA receptors are overactivated and this leads to too much glutamate, causing the cell to die Autophagy - Answers a cell is engulfed to make an autophagasome. this autophagasome then goes on to fuse with the lysosome, destroyed the cellular contents What are some characteristics of a cell dying by autophagy? - Answers no nucleus, cytoplasm gets more electron dense, mitochondria dense and clustered, accumulation of vacuoles What is the defined process by which apoptosis occurs? - Answers 1) condensation of nuclear material (pyknosis) 2) plasma membrane "blebs", creating small fragments 3) cell fragments are eaten by nearby phagocytes 4) chromosomes get cleaved into nucleosome sized fragments What is the histological way to detect apoptosis? - Answers TUNEL assay