Answer:
The correct answers are: Neurotransmitter Vesicles, Acetylcholine, Contraction.
Explanation:
- At the neuro-muscular junction, impulses are transmitted in the following manner:
- The impulse is carried by an action potential (variable opening and closing of different ion channels located on the membrane of the neurons allowing variable ion movement) to the neuron at the neuro-muscular junction.
- The action potential causes the opening of the voltage dependent calcium channels in the axon terminal of the neuron allowing the entry of calcium ions.
- This causes the neurotransmitter vesicles containing the neurotransmitter acetylcholine to fuse with the pre-synaptic membrane.
- Acetylcholine is released by the method of exocytosis into the synaptic cleft.
- The acetylcholine molecules bind to the the cognate receptors present in the membrane of the muscle cell (sarcolemma).
- This causes the flow of sodium ions into and potassium ions out of the muscle cell, which generates action potential in the muscle cell.
- This action potential causes the muscle cell to contract.
Answer:
According to the characteristics given and what the image shows, the species to which the frog corresponds is Bufo boreas.
Explanation:
Options for this question are:
- <em>Bufo marinus
.</em>
- <em> Litoria caerulea
.</em>
- <em>
</em><em>Bufo boreas.
</em>
- <em>
Acris crepitans.</em>
Bufo boreas is a species belonging to the family Bufonidae, very common in North America, constituting an anuro amphibian.
The appearance of B. boreas is that of a thickened and irregular skin, due to multiple warts found on its surface. Additionally it has a stripe or line in its dorsal region, which extends from the head to the tail.
These characteristics, together with the description given, make it possible to establish that B. boreas is the species that can be observed in the picture (see image).
Xx - female. Xy - male. egg already has an X chromosome so it depends on the other. If second one is X than it's a girl. If Y - a boy
