Here's a few: magnesium, oxygen, silicon, phosphate, and aluminum are all found in earth's crust in high proportion. oxygen being the highest proportion of any other element.
D - spine alignment and foot size.
Late australopiths had an S-shaped spine that allowed for balance when standing. Shorter and less flexible toes made pushing off the ground much easier.
Answer:
Zooplankton help other populations survive by keeping out other herbivores
Explanation:
This is because a keystone species are species that have large effect on the the habitat and through its effect they help to keep the ecosystem in existence. They make sure that the ecosystem exist. They help populations survive by keeping out herbivores and feeding on the algae. They help drive nutrients cycle and transfer energy from algae to invasive fish.
Answer:
B. The membrane lets certain substances move across it freely, while others must move through a “gate”.
Explanation:
Selective permeability is a property of cellular membranes that only allows certain molecules to enter or exit the cell. This is important for the cell to maintain its internal order irrespective of the changes to the environment. For example, water, ions, glucose and carbon dioxide may need to be imported or exported from the cell depending on its metabolic activity. Similarly, signaling molecules may need to enter the cell and proteins may need to be released into the extracellular matrix. The presence of a selectively permeable membrane allows the cell to exercise control over the quantum, timing and rate of movement of these molecules.
