Hello everyone, please help me solve a question where is the rings of a shark 20

The growth rings of sharks are on dorsal fin spines.

What is the relationship between the age of fish and the scales?

Many people can tell the age of a fish by looking at its scales, but what's the secret? From the growth pattern of fish, we know that most fish have tiny scales all over their bodies in the first year of life. The scales consist of many flakes of different sizes, like a cone with a truncated spire, thick in the middle, thin on the sides, the top layer the least, but the oldest; The bottom layer is the largest, but the youngest.

As the scales grow, new lamellae are formed on its surface, and the number of lamellae increases as the fish ages. Fish grow at different rates throughout the year. Usually it grows fast in spring and summer, slows down in autumn, stops growing in winter, and resumes growth the following spring.

The same is true for scales, which are wider in spring and summer, narrower in autumn, and stop growing in winter. Flakes of different widths are stacked on top of each other in an orderly manner around the center, one after the other, forming many bands called "growth zones." The number of years in which the fish grows corresponds to the number of years the fish has experienced.

There is a clear boundary between the broad flakes produced in spring and summer and the narrow flakes produced in autumn that are closely arranged, and there is a clear boundary between the first and second growth zones, which is called "growth rings". Fish with more rings are older, and fish with fewer rings are younger. Therefore, by looking at the scales of the fish, according to the number of rings, you can calculate the exact age of the fish.

Once you've caught a fish, try to see how old it is. The use of fish scales to determine the age of fish has been widely used by many anglers, but it is not the only method. Because some fish do not have scales, the age of the fish is also determined by using the fish's vertebrae, operculum, otoliths, etc. as observation materials.

The method of observation is similar to that of fish scales, which uses the "growth rings" formed by the fish due to different growth periods to determine the size of the age.

Sharks use scales to calculate their age. The scales are first placed in ammonia-dissolved alcohol (one part ammonia plus two parts 90 parts alcohol, or two parts benzene and one part ether to make a potion, or alcohol). First wash it with the above potion or alcohol, remove the fat and other debris on it, and then put it under a magnifying glass to observe, you can see the concentric circles on the scales, which is its "growth ring", and the number of concentric circles can know the age of the fish.

The growth of fish varies with the seasons, and this uneven growth is reflected in the scales like tree rings.

Note: The scales of sharks are extremely small, and a magnifying glass of a larger magnification should be applied.

Sharks use scales to calculate age.

Use scales to calculate age.

Sharks do not have scales, and sharks' growth rings are on dorsal fin spines.

Where are the rings of the big tree facing? A trick teaches you to look at the annual rings and identify the direction.

Mammals such as horses, cows, sheep, camels, mules, etc., all leave growth rings in the process of calcifying their teeth. Therefore, many experienced old farmers in the countryside can accurately tell the age of cows, horses, etc., just by looking at their teeth.

The growth rings of reptiles, such as turtles and turtles, are "carved" into the carapace on their backs. Coelenterates, such as corals, have growth rings on their surface walls, which are distinguished by regular stripes of varying thickness.

The growth rings of fish are on the scales. Due to the high temperature and sufficient bait in spring and summer, the scales grow quickly and form wide concentric circles; In autumn and winter, the water temperature is low, the bait is scarce, and the scales grow slowly, leaving only narrow concentric circles. There is a clear boundary between the wide and narrow concentric circles.

How do you tell the age of a fish?

There are no sharks in the offshore, so if you want to dive, you can go to a special diving area, where there are shark nets!

There are a lot of small sharks, but there are no big ones, shark fins are valuable, and big sharks suffer

Man has annual rings. Did you talk about bone age? It is the annual rings of the bones, and when the general test is specialized, put the hand of the genus that is not often used into a small box-like instrument, and take a **, you can see your bone age, and the age of this person is very accurate.

Because humans are also a living being, there are many factors that determine a person's age. For example, sex hormones, amount of exercise, metabolism. And so on, so you can't say what your birthday is, how old you are.

Generally, when the national team is playing, there will be this test. I'm afraid it's a false report of the account. And the unfairness of the competition is the measurement of bone age.

Some children, for example, are really 15 years old. However, the bone age is on the high side. Like a tree, if it has more than 15 circles, then its real age is large.

It is possible that human growth and development determine true age.

People are not plants, so there is no - that's the official answer.

Men have growth rings, and you can see them when you peel back the little jj - that's my answer.

Growth rings are the traces left by the dead bark to regenerate.

The annual rings of cattle and horses are reflected in the teeth, and people who have experience in raising cattle and horses can quickly and accurately tell the age of cattle and horses by looking at the teeth of the first few glances of cattle and horses. The coral, which enjoys the reputation of "the flower of the sea", has regular ring-shaped stripes of thickness on the surface wall, each stripe is one year old, and the more stripes, the older the age.