Answer:
A. The poles are opposite
Explanation:
Magnets are object that produce magnetic fields, which are regions of space that exert a forces on charged particles in motion or on other magnets.
Every magnet has 2 opposite poles, which are labelled by convention as North Pole and South Pole; the lines of the magnetic field of a magnet go out from the North Pole and go into the South Pole.
Magnetic poles always exist in pair: it means, every magnet always contains a North Pole and a South Pole. If a magnet is cut in a half, each half of the magnet will still have a North Pole and a South Pole.
Each pole exerts a force on another pole; in particular, we have:
- Like poles (north-north or south-south) repel each other
- Opposite poles (north-south) attract each other
In this problem, a magnet is attracted to a metal object: this means that the two poles must be of opposite polarity. Therefore, the correct option is
A. The poles are opposite
Answer:
yes. a ecosystem consist of both biotic and abiotic factor
Answer:
According to the sliding-filament model of contraction, the muscle contraction occur due to the myosin heads propel the actin myofilaments toward the center of the sarcomere. This pulls the Z disks closer together, shortening sarcomere and the entire muscle
Explanation:
In the muscle fiber there are two proteins that facilitate the process of contraction, myosin and actin. Myosin is thicker and more abundant than actin, and its interaction is responsible for the process of muscle contraction.
Both molecules, myosin and actin, form bonds -called cross bridges- where the myosin heads produce the mobilization of actin towards the center of the sarcomere. Z discs are associated with actin myofibrils, so they come close, and promote the shortening of the sarcomere.
This process requires the action of calcium ions, which depolarize the muscle cell and consume energy in the form of ATP.
It should be noted that the myosin and actin molecules do not change their length, but their action causes the muscle fibers to shorten during contraction.
Learn more:
Types of muscle contraction brainly.com/question/7117064
Answer:
Explanation:
If we break down the word autotroph, auto means “self” and troph means "feeding" or nourishment. However, when we break the word heterotroph, we get hetero- meaning other, and troph meaning feeders.
This is the critical difference between these two groups. Autotrophs synthesize or make their own food whereas, heterotrophs cannot make their own food thus have to rely on others by eating or absorbing others. For example, plants are autotrophs because they can make their own food using photosynthesis, whereas, humans are heterotrophs because we have to eat others to survive.
