In this animation, we delve into the different functions and components of blood. Blood is a mixture of various cells suspended in a fluid called plasma. Although fundamentally different in both appearance and function, all blood cells originate from a single type of stem cell in the bone marrow. Red blood cells, or erythrocytes, are made up of little sacs of haemoglobin which are designed to carry oxygen. White blood cells, or leukocytes, are part of our immune system and move in and out of blood vessels searching for any signs of infection or cellular abnormalities. Platelets, or thrombocytes, help repair the blood vessel in the event of an injury by helping the blood to clot.
By: Charlotte Silver
San Francisco Bay Area Palestine activists have declared their first victory in attempting to prevent the offloading of an Israeli cargo vessel at the Oakland Port. Originally planning to show up at 5:00 am Saturday morning to block the ship, activists sent word out late last night that the meeting time had been moved up to 3:00pm, as the ship had delayed its arrival at Oakland in an apparent attempt to avoid the protest.
Activist Mohamed Shehk told The Electronic Intifada that the organizers have been tracking the vessel Zim Piraeus, and realized last night that it had stopped before reaching its Oakland destination, spending the night at sea.
“This delay is seen as a victory for us. It shows how much Zim is trying to avoid our protest, and it shows how effective we can be when we can organize these types of actions,” Shehk said.
This is the blood vessel network of the human face.
There are three varieties of blood vessels: arteries, veins, and capillaries. During blood circulation, the arteries carry blood away from the heart. The capillaries connect the arteries to veins. Finally, the veins carry the blood back to the heart.
If you took all of the blood vessels out of an average child, and laid them out in one line, the line would be over 60,000 miles long! An adult’s vessels would be closer to 100,000 miles long!
Besides circulating blood, the blood vessels provide two important means of measuring vital health statistics: pulse and blood pressure. We measure heart rate, or pulse, by touching an artery. The rhythmic contraction of the artery keeps pace with the beat of the heart. Since an artery is near the surface of the skin, while the heart is deeply protected, we can easily touch the artery and get an accurate measure of the heart’s pulse.