For centuries scientists thought the Universe always existed in a largely unchanged form, run like clockwork thanks to the laws of physics. But a Belgian priest and scientist called George Lemaitre put forward another idea. In 1927, he proposed that the Universe began as a large, pregnant and primeval atom, exploding and sending out the smaller atoms that we see today.
His idea went largely unnoticed. But in 1929 astronomer Edwin Hubble discovered that the Universe isn’t static but is in fact expanding. If so, some scientists reasoned that if you rewound the Universe's life then at some point it should have existed as a tiny, dense point. Critics dismissed this: the celebrated astronomer Fred Hoyle sarcastically called this concept the “Big Bang Theory"
Observation is a factual statement that cannot be changed or replaced.
Explanation)
Hypothesis is a tentative statement that can be tested.
Scientific law and theory are considered a fact but can be disproven if new evidence emerges.
4.Metaphase
All of the chromosomes are aligned midway between the
spindle poles. A spindle is a dynamic network of microtubules that
attaches to and moves chromosomes during nuclear division. Microtubules
attach each chromatid to one of the spindle poles, and its sister to the
opposite pole.
Answer:
Below
Explanation:
4) An endoskeleton is an internal skeleton made out of mineralized tissue that is attached to muscles as well as enabling movement.
5) An exoskeleton is the external skeleton that supports and protects an animal's body. As an example, a snail's shell is an exoskeleton
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