Answer:
1. The presynaptic neuron reaches the synaptic knob and the terminal is depolarized.
2. The electrical voltage gated calcium channels in the presynaptic knob opens.
3. The calcium ions enters through the calcium channel, this calcium ions cause the fusion of the synaptic vesicles to the presynaptic membrane, the cell membrane of an axon terminal that faces the receiving cell.
4. There is neurotransmitter release by the axon terminal of a neuron and bind to and react with the receptors on the dendrites of another neuron e.g. acetylcholine by exocytosis.
5. Acetylcholine diffuses across the synaptic cleft and bind to receptors on the postsynaptic neuron, that is a neuron to the cell body or dendrite of which an electrical impulse is transmitted across a synaptic cleft by the release of a chemical neurotransmitter from the axon terminal of a presynaptic neuron.
6. This causes sodium ion channels in the postsynaptic neuron to open, and sodium ions diffuse in.
7. Excitatory (excited neurons) postsynaptic potentials are created, and if these generator potentials are sufficient then the postsynaptic terminal reaches threshold potential and there is propagation.
Explanation: The nervous system is made up of billions of specialized cells called neurons, it is crucial to have an efficient communication between neurons for normal functioning of the central and peripheral nervous systems. The presynaptic action potential refers to an action potential of neuron before synapse. The above is the sequence of event during the transmission of information across the synaptic cleft
Answer:
Explanation:
Biological membranes have three primary functions: (1) they keep toxic substances out of the cell; (2) they contain receptors and channels that allow specific molecules, such as ions, nutrients, wastes, and metabolic products, that mediate cellular and extracellular activities to pass between organelles and between the
Producers are organisms that make their own food. Plants would be an example. Primary consumers would be those that eat producers(plants,algae). Secondary consumers are animals that eat primary consumers. Herbivores are animals that only eat plants. Carnivores are those that only eat meat and don’t eat plants. Omnivores are those that eat both meat and plants. De composers are those that decompose organic material like dead animals. The herbivores here are the kangaroo rats,grasshoppers and bunny’s. The carnivores here are the hawk,lizard,tarantula and rattlesnake. I don’t think there is an omnivore. And the only decomposed here is the bacteria. As it decomposes the bodies of the animals when they are dead.
During meiosis, two successive nuclear divisions happens namely Meiosis I or reduction and Meiosis II or division. In meiosis I, it separate chromosomes after allowing crossing over. In meiosis II, it the then separates each chromosomes by splitting them. This division produces 4 haploid cells.
Answer:
Epiphyseal plate
Explanation:
The growth plate is a thin layer of cartilage that lies between the epiphyses and metaphyses, and is where the growth of long bones takes place.
