a hole happening at consistent interims between portions of myelin sheath along a nerve axon.
Answer:
Your heart changes its rate depending on the activity, so that it can carry blood to your muscles, and therefore it needs to beat stronger if you are performing some exercise, or not so strong if you are sleeping, for example.
Explanation:
Your heart is continuously beating to keep blood circulating throughout your body.
So, here it is why your heart changes its rate: Its rate changes depending on your activity level; it is lower while you are asleep and at rest and higher while you exercise to supply your muscles with enough freshly oxygenated blood to keep the functioning at a high level.
And how: depending on your activity level, your heart has to pump enough blood to your muscles. Blood carries needed oxygen and other nutrients. Muscles need more blood sugar than any other tissue especially when working hard. To supply your muscles with oxygen your heart needs to beat faster, and this builds up your heart muscles.
Octopus and squid have little suction cups on their tentacles. It helps with sticking onto food (so it doesn't get away) and also helps with sticking into things. If it wanted to camouflage into some rocks, it can use its tentacles to cling to to the rock.
Tentacles can also grab and carry things. Scientists have made tests where they would put a clam in a jar with the lid screwed on. The octopus would grab onto the jar and use its tentacles to twist the lid off.
Without tentacles, octopuses and squids would be pretty helpless and probably couldn't survive in the deep ocean.
An egg developes to a new into a new animal after its fertilized by the male reproductive cell or sperm. No matter how an animal reproduces its eggs it must provide ways or nourishing and protecting the developing embryo. Have a great day hope this helps you :)
