Answer:
The platypus serves as a 'bridge' animal between nonmammals like birds and reptiles, which maintain their testicles in their body cavity, and placental and marsupial mammals, which hold their testes in an external scrotum."
Answer:
The structure of mitochondria contains the foldings in the inner side called "cristae" which increase the surface area of the mitochondria. The cristae are important to mitochondria as well as cell as cristae embody the ATP synthase enzymes which help in the formation of the ATP molecules.
Heart cells require more energy to pump the blood from the heart to the body so it needs a more mitochondrial number in the cells with more infoldings to synthesize more ATP.
Balancing, running, and jumping are all examples of <em>gross</em> motor skills.
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I quote from Wikipedia:
"Gross motor skills are the abilities usually acquired during childhood as part of a child's motor learning. By the time they reach two years of age, almost all children are able to stand up, walk, jump, run, walk up stairs, etc. etc."
i think it is D. B. AND C. im sorry if im wrong