Answer:
Ecology is the study of organisms and how they interact with the environment around them. ... Changes in ecosystems can result from many different factors including diseases among the organisms living in the area, increases in temperature, and increased human activities.
Explanation:
A change in allele frequencies.
Answer:
All animals are eukaryotic, multicellular organisms, and most animals have complex tissue structure with differentiated and specialized tissue. Animals are heterotrophs; they must consume living or dead organisms since they cannot synthesize their own food and can be carnivores, herbivores, omnivores, or parasites
Explanation:
Calcium can be found in eggs,milk,meat,etc
Calcium is not a rare element
Hope i helped you
