Blood type

Do you know your blood type? If you haven’t been in any medical situations where blood type is important, you might not.

We know that there are 8 main blood groups that make up most of the world’s population.

But it turns out that scientists still don’t know why we evolved different blood types. And that may remain a mystery for a long time. But from now, science can at least tell you about your own blood.

Knowing your Blood type

In develops parts of the world, it’s not crucial to know your blood type off the top of your head. Doctors will typically run tests before any major procedure and if there’s any doubt in a medical emergency, you’ll most likely receive O negative blood, because that’s the universal donor blood that’s save to give to any A, B, AB or O recipient.

Blood type experiments

For thousands of years nobody really understood blood. A Greek doctor Claudius Galenus from 200 CE believed that it was created food and liver, and this school of thought lived on for nearly 1500 years.

It wasn’t until in the 17th century A british doctor named William Harvey, discovered that blood actually circulated through the body. This spawned A new age of experimentation with blood.

In 1665, an English physician successfully kept one dog alive by transfusing it with a blood of another dog. Just two years later, doctors began experimenting with Xenotransfusions. That is transfusing humans with animal blood, such a sheep. And those human patients died.

It wasn’t until 1900 that we finally realised people and animals actually have different types of blood that determine whose blood can mix with whose. That’s where different letters came into play.

If you’re type A, your immune system will perceive type B blood as an intruder and trigger auto immune response that can cause

  • kidney failure,
  • extensive blood clotting, and
  • even shock.

The reverse is true of type B blood. The immune system will attack type A.

AB blood however, accept both A and B blood without triggering the auto immune response. These things get little bit complicated when introduced there negative and positive part of your blood type. Positive can’t accept negative, but the opposite is extremely dangerous.

Other than 8 Blood types

To further complicate things scientists have discovered dozens of more blood type, such as the Duffy blood group, which can determine your susceptibility to malaria. Or the Hh blood type, which 1 in 10,000 people in India have. But the vast majority of the humans fall into this A, B, O system.

As per why humans evolved this complicated system of blood types and compatibility, we really don’t know. The original mutations are thought to date back nearly 20 million years. But whatever the biology is behind blood typing, it’s a real practical thing that matters.

It’s just not a bad idea to know your blood type. If you’re traveling somewhere that’s rural, or doesn’t have access to advance medicine, it’s good for you and your travelling companion to know your types, just in case of an accident along the way. In big emergency closer to home, blood banks often put in calls for donors of a specific type. And remember if you’re type O Negative, you’re an extremely useful universal donor. So, knowing your type can give you a peace of mind.

Your body when you Swim

Harvard medical school published a study which looked at over 40,000 men, aged 20-90 who were either runners, walkers, swimmers, and physically in active people. With an average length of 13 years of observation and in that time

  • 2% of swimmers passed away
  • 8% of runners passed away
  • 9% of walkers passed away
  • 11% of physically inactive people passed away

This study showed that swimmers are much healthier later on in life than the rest of the population and for women swimming just 30 mins a day can decrease coronary heart disease by 30 to 40 percent.

It also helps to increase HDL aka good Colestrol. Some studies have also shown that aerobic excercise can keep the cells in the lining of your arteries more flexible and healthier. Hence there is no question that swimming is an awesome form of fitness.

Body during swimming

What do you actually feel when you go into the water? Here are some main elements of the human body that gets impacted during swimming.

1. Blood

According to the America Heart Association, swimming is considered as Aerobic activity. Aerobic excercise enlarges the heart and it increases the blood flow through the entire boby. Because swimming is an excercise, the blood has to pump all the molecules into the body.

2. Heart

Since so much of blood has to be pumped into the body, that ties into how it impacts your heart because we know that after 2 mins your body goes into aerobic respiratory because your heart has to pump all the oxygenated blood through the body. So as you swim, your heart is circulating the blood which help your body to perform and achieve the required goals.

3. Skin

You must have seen that the skin color changes of swimmers. For example, some swimmers face turns red when the swim, that happens because your blood vessels are dilating and the brings the heat to the surface into the skin then some people turn red, as a result your skin is showing the effort that you’re putting in the water.

4.Muscles

There’s a reason why swimmers are considered to have best body and physiques in the world compared to any athlete, because swimming engages every single muscles in the water when it comes to your core stability, your upper body, your biceps, your hamstrings, your calves, everything is engaged when you swim.

When you’re swimming, you are micro tearing your muscles while swinging it. And the muscles requires 24-48 hrs to recover those muscles. That’s when sometimes you might feel sore.

5. Lungs

Swimming can actually help increase your lungs volume because in swimming different than other sports, you can’t actually breath whenever you want. It’s not like running when you have full access to oxygen.

In swimming you’re engaging your muscles and you’re not allowed to breathe necessarily at the time when your body might want it. So because you have to get used to this, you actually increase your Vo to max (maximum amount of oxygen body is able to use). So basically you are making your lungs more efficient at functioning.

6. Brain

The Brain loves swimming, because of all the extra blood flow moving through these endorphins that makes you more awake, alert and focus.

But this could happen in any type of sport but swimming is something really special because you’re sort of in your own world where the medium is 800 times more dense than air, which makes you feel free and relaxed.

Hence, from physical health to mental health, swimming is an incredible benefit human body and after reading this you must be thinking of trying swimming.

FACTS ABOUT STARFISH

Starfish (or sea stars) are beautiful marine animals found in a variety of colors, shapes, and sizes. All starfish resemble stars, and though the most common have only five arms, some of these animals can grow up to 40 arms. The amazing sea creatures—part of a group of animals known as echinoderms—travel using their tube feet. They can regenerate lost limbs and swallow large prey using their unusual stomachs.

Sea Stars Are Not Fish

Although sea stars live underwater and are commonly called “starfish,” they are not true fish. They do not have gills, scales, or fins like fish do.

Sea stars also move quite differently from fish. While fish propel themselves with their tails, sea stars have tiny tube feet to help them move along.

Because they are not classified as fish, scientists prefer to call starfish “sea stars.”

Sea Stars Are Echinoderms

Sea stars belong to the phylum Echinodermata. That means they are related to sand dollars, sea urchins, sea cucumbers, and sea lilies. Overall, this phylum contains approximately 7,000 species.

Many echinoderms exhibit radial symmetry, meaning their body parts are arranged around a central axis. Many sea stars have five-point radial symmetry because their body has five sections. This means that they do not have an obvious left and right half, only a top side and a bottom side. Echinoderms also usually have spines, which are less pronounced in sea stars than they are in other organisms such as sea urchins.

There Are Thousands of Sea Star Species

There are about 2,000 species of sea stars.2 Some live in the intertidal zone, while others live in the deep water of the ocean. While many species live in tropical areas, sea stars can also be found in cold areas—even the polar regions.

Not All Sea Stars Have Five Arms

While many people are most familiar with the five-armed species of sea stars, not all sea stars have just five arms. Some species have many more, such as the sun star, which can have up to 40 arms.

Sea Stars Can Regenerate Arms

Amazingly, sea stars can regenerate lost arms, which is useful if a sea star is injured by a predator. It can lose an arm, escape, and grow a new arm later.

Sea stars house most of their vital organs in their arms. This means that some species can even regenerate an entirely new sea star from just one arm and a portion of the star’s central disc. This won’t happen too quickly, though; it takes about a year for an arm to grow back.

Sea Stars Are Protected by Armor

Depending on the species, a sea star’s skin may feel leathery or slightly prickly. Sea stars have a tough covering on their upper side, which is made up of plates of calcium carbonate with tiny spines on their surface.

A sea star’s spines are used for protection from predators, which include birds, fish, and sea otters. One very spiny sea star is the aptly named crown-of-thorns starfish.

Sea Stars Do Not Have Blood

Instead of blood, sea stars have a circulatory system made up primarily of seawater.

Seawater is pumped into the animal’s water vascular system through its sieve plate. This is a sort of trap door called a madreporite, often visible as a light-colored spot on the top of the starfish.

From the madreporite, seawater moves into the sea star’s tube feet, causing the arm to extend. Muscles within the tube feet are used to retract the limb.

Sea Stars Eat With Their Stomachs Inside-Out

Sea stars prey on bivalves like mussels and clams as well as small fish, snails, and barnacles. If you’ve ever tried to pry the shell of a clam or mussel open, you know how difficult it is. However, sea stars have a unique way of eating these creatures.

A sea star’s mouth is on its underside. When it catches its food, the sea star will wrap its arms around the animal’s shell and pull it open just slightly. Then it does something amazing: the sea star pushes its stomach through its mouth and into the bivalve’s shell. It then digests the animal and slides its stomach back into its own body.

This unique feeding mechanism allows the sea star to eat larger prey than it would otherwise be able to fit into its tiny mouth.

Sea Stars Have Eyes

Many people are surprised to learn that starfish have eyes. It’s true. The eyes are there—just not in the place you would expect.

Sea stars have an eye spot at the end of each arm. This means that a five-armed sea star has five eyes, while the 40-armed sun star has 40 eyes.

Each sea star eye is very simple and looks like a red spot. It doesn’t see much detail but it can sense light and dark, which is just enough for the environments the animals live in.

All True Starfish Are in the Class Asteroidea

Starfish belong to the animal class Asteroidea. These echinoderms all have several arms arranged around a central disk.

Asteroidea is the classification for “true stars.” These animals are in a separate class from brittle stars and basket stars, which have a more defined separation between their arms and their central disk.