Answer:
um el cielo se va a nublar ,aves se iran volande de la zona,se pondra mas frio y comensara a llover y hacer mucho viento
Explanation:
Answer:
D. Calcium ions.
Explanation:
Here we are talking about the mechanism of muscle contraction. The most accepted theory of muscle contraction is sliding filament theory. It was given by Huxley and Huxley. During the process actin filaments slides over myosin filament by forming cross bridges. The sequence of events are as follows:
a. An action potential propagates through the motor nerve and reach the nerve endings on the muscle fiber at neuro-muscular junction.
b. Neurotransmitter called acetylcholine is released by the nerve endings.
c. Acetylcholine binds to the receptors on muscle fiber and opens the gated channels which causes flow of Na+ ions into the muscle fiber.
d. This influx of sodium ions initiates an action potential in the muscle fiber which reaches the T- tubules or transverse tubules. Here it causes the sarcoplasmic reticulum to release large amounts of calcium ion.
e. Calcium ions are responsible for initiating the attractive forces between actin and myosin filaments. Cross bridges are formed, actin slides over myosin causing the contraction of muscle.
Crocodiles belong to Reptiles. Reptiles are <span>a cold-blooded vertebrates. </span>
Answer:
Option (D)
Explanation:
The tropical rain forest and tropical dry forest lies on the tropical regions of both the hemisphere. These are the regions on and around the tropic of cancer and tropic of capricorn. In the tropical rain forest, the rate of precipitation is higher than the rate of evapo-transpiration, so the temperature remains relatively cooler. Whereas, in the tropical dry forest, the rate of evapo-transpiration is more than the rate of precipitation, as a result of which the temperature remains comparatively high.
The tropical dry forest is very good for agricultural purpose, as it contains nutrient rich soil. So it has been destroyed to a greater extent for agricultural use, grazing of animals.
Whereas, the tropical rain forest is not suitable for the agricultural use because the soil here are affected by the rainfall, that washes away the nutrients, making the soil less fertile.
Thus the correct answer is option (D).
Answer:
Lake Titicaca
Explanation:
Which is located in peru.
