Answer:
The source of Calcium (Ca⁺⁺) for the skeletal muscle cells is the sarcoplasmic reticulum, the main store of intracellular Ca⁺⁺.
Explanation:
Calcium (Ca⁺⁺) is an ion that plays an important role in muscle contraction, a process that requires high cytoplasmic concentrations of this ion to promote myofibrillary activity.
The sarcoplasmic reticulum (SR) -equivalent to the endoplasmic smooth reticulum- is an organelle that regulates the contractile activity of skeletal muscle. The two terminal cisterns of the SR attach to the T-tube, forming a triad, which surrounds the myofibrilla.
Once the muscle cell receives the signal to contract, the Ca⁺⁺ channels are opened and allow Ca⁺⁺ to enter the cell, promoting the exit of this cation from the SR and increased its cytoplasmic levels. This stimulates muscle contraction.
The quality of hr claim is not only weak because of she uses an unreliable source, but it could also makes her look bias because she does not acknowledge the other side which makes her claim not thorough enough to be valid.
Answer;
-Tropical rainforest; tropical seasonal forest
In contrast with the tropical rainforest, the soil of the tropical seasonal forest is more nutrient-rich and this type of biome has fewer insects, parasites, and fungal diseases. therefore, in many places, these areas are highly endangered.
Explanation;
The tropical rainforest is one of the world's most threatened biomes, despite being home to some of the most diverse and unique species on the planet. The tropical rainforest is a biome with a constant temperature and a high rainfall. The level of humidity and density of the vegetation give the ecosystem a unique water and nutrient cycle. Rainforests around the world are threatened by human expansion.
The tropical seasonal forest has more or less densely growing trees which lose their leaves during the dry season. It typically contain a range of tree species: only some of which drop some or all of their leaves during the dry season.
The appropriate answer is c. a tertiary consumers. Tertiary consumers are usually carnivores that eat other carnivores. The grass in the food chain is the primary producer. Primary producers are plants who get their energy from the sun. The grasshoppers are primary consumers or herbivores. The frogs are secondary consumers and they are also carnivores. A food chain shows how energy is passed on in an ecosystem.
