Answer: c. It is the first hominin known to have migrated out of Africa.
Explanation:
The Homo erectus were the ancient humans which are considered to be over first relatives which used to have human like body shape, short arms and long legs relative to their torso. The main unique feature about these humans is that these were the first humans which migrate out of the Africa and they were the first humans who starting cooking of food for the first time.
Answer:
Increased exposure to X-rays
Explanation:
X-rays shoot harmful radiation through your body, that's why when you go to the dentist or other places and they take a X-ray they give you a lead vest to protect your organs from unneeded radiation.
hope this helps :)
Answer:
The correct answer will be option-D.
Explanation:
Calcium plays an important role in muscle contraction as they are released from the sarcoplasmic reticulum after they receive electric impulse.
Calcium triggers the muscle contraction cycle as these calcium ions bind to the troponin-tropomyosin complex. This binding exposes the myosin-binding site on the actin on which high energy myosin binds and cross-bridge is formed.
This cross-bridge formation causes the contraction of the sarcomere and therefore muscle contracts.
Thus, option-D is the correct answer.
