Normal polarity
Explanation:
Earth's magnetic field used to be twice as strong 1.5 billion years ago as it is today and Earth's temperature other than what the geologists see from the 'normal' pattern. It has been noticed that some volcanic rocks were magnetized in opposite direction to the direction of the local Earth's field. It is clear that the Earth has experienced the normal polarity 1.5 years ago but at that time, the Earth's polarity was poorly understood.
Answer – 3. A weakened form of a virus
When getting a vaccination, the substance which is injected into the body is a weakened form of a virus. This weakened from of the virus has the ability to arouse the body’s defense mechanism without causing an infection.
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<span>a. Fish have a single central heart; earthworms have several hearts.
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Multi cellular organisms are made up of billions of cells each specialized to a unique role and these cells are organized into structural and functional units such as tissues and organs.
For each cell and organ to function optimally, it requires oxygen and nutrients and needs carbon dioxide and metabolic waste taken away in a continuous, never ending process.
<span>A mechanism is needed to accomplish the important function of transporting the relevant materials to and from the cell. The circulatory system fits this bill splendidly. It is a specialized organ system which allows blood and lymph to flow through the entire body carrying nutrients such as glucose, amino acids and electrolytes as well as oxygen to each cell, at the same time carting away carbon dioxide and all sorts of metabolic waste over to excretory organs to be expelled from the body.
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The swim bladder is more or less an oval, soft-walled pouch located in the abdominal cavity, just below the spinal column. Its shape varies greatly, but the volume is constant between species, most often around 5% of body.
<h3>Day of deep-sea fishing</h3>
1. The volume of your swim bladder when you put it back in the water would be 7.5 liters.
2. The time the fish would float on the surface before the oval could restore neutral buoyancy would be a few seconds.
3. If I were a red blood cell that has just delivered its oxygen to the tail musculature of a mako shark, the route through the circulatory system to eventually reach the mako's swim bladder would be the venous route, like other fish, they have a heart with two chambers, an atrium and a ventricle, and closed circulation.
With this information, we can conclude that the volume of her swim bladder when she was put back in the water would be 7.5 liters.
Learn more about swim bladder in brainly.com/question/22849660
Which organelle controls cellular activity comparable to the way the brain controls body activity? The cell membrane
