Answer:
C
Explanation:
it is called point because the source can be identified
Answer:
It allows them to save energy
Explanation:
Hibernation is a behavioral adaptation that involves physiological changes to survive during wither months. These physiological changes can include a decrease in body temperature, respiratory/heart rate and metabolism. The main purpose for which animals enter hibernation is to conserve energy, thereby surviving adverse climatic conditions and/or periods when food is scarce. Some examples of true hibernators (i.e., animals that enter into a state of minimal activity) include bats, hedgehogs, allies, squirrels, marmots, etc.
Answer:
difference:
1. The generation mechanism is different, the mechanical wave is generated by mechanical vibration; the electromagnetic wave generation mechanism is also different, there is the periodic movement of electrons (radio waves); the outer electrons with atoms are generated after being excited (infrared, visible, ultraviolet) The inner electrons with atoms are generated after excitation (roentgen rays); the nuclei with atoms are generated after excitation (gamma rays).
2. The propagation mechanism is different: the mechanical interaction between the particles and the alternating induction of the electromagnetic field.
3. Mechanical waves have both transverse waves and longitudinal waves; electromagnetic waves are material waves and belong to transverse waves.
4. The influence of the medium on the propagation speed is different
Explanation:
https://qiaodahai.com/similarities-and-differences-between-mechanical-waves-and-electromagnetic-waves.html
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.
Spermatogenesis produces<span> four </span>gametes<span>, while </span>oogenesis produces one with two to three polar bodies left over. because oocytes contain not only genetic material but also mitochondria.
