Answer:
D. Nuclear fusion begins under high pressure.
Explanation:
A star is a giant astronomical or celestial object that is comprised of a luminous sphere of plasma, binded together by its own gravitational force.
Some of the examples of stars are;
- Sun (closest to the Earth)
Stars are typically made up of two (2) main hot gas, Hydrogen (H) and Helium (He). The chronological order in which the formation of a star occur are;
1. Gravity pulls gas and dust together to form dense cores.
2. A protostar forms as mass increases.
3. Nuclear fusion begins under high pressure.
Hence, the final event that occurs when a star is forming is that nuclear fusion begins under high pressure.
<span>Males and females are attracted to each other in order to ensure the viability and fertility of the offspring, which is also why it is uncommon that males of one species be attracted to females of another. Members of two different species cannot mate and thus cannot produce fertile, viable offspring, unless they are part of different sub-species. But they must be part of the same species.
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Answer: the tundra is important to protect is that it serves as a habitat for migratory populations, like waterfowl, shorebirds, caribou and several bear species. It is home to endangered animals such as the Arctic Fox, Polar Bear, Grizzly Bear, Caribou, and Musk Ox.
Explanation:
Answer::: Brain structures called the hypothalamus and pituitary gland control the menstrual cycle. The hypothalamus triggers the pituitary gland to make hormones that trigger the ovaries to make oestrogen and progesterone. ... Disorders of the hypothalamus, pituitary gland or ovaries can affect menstruation, causing amenorrhoea
Plants produce oxygen that animals use for respiration
