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What was the name of Neil Armstrong's shuttle?

Neil Armstrong was the first man to step on the moon on July 20, 1969. He became an astronaut in 1962 after serving as a naval aviator and a research pilot. In 1966, he and David Scott flew on Gemini 8. After his moon landing, Armstrong became the Deputy Association Administrator for Aeronautics for NASA before resigning in 1971. In 1986, he sat on the presidential commission investigating the tragic circumstances of the space shuttle Challenger.

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What are some examples of sound waves?

Sound waves are created by the vibration of an item, which then produces a pressure wave that displaces the air. The displacement vibrates the ear drum in the ears and is registered as a sound by the brain.\n\nSounds waves can pass through mediums such as air, water, gases and solids. Longitudinal waves will go through compressible mediums, while transverse waves go through solid objects such as wood. However, the particles within the medium do not travel with the sound wave.

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What is the role of carotene and xanthophyll?

Carotenoids are fat-soluble pigments attached to the wall of chloroplasts in which they are synthesized and stored. Carotenes are reddish-orange pigments that contain only one carbon and hydrogen atom. Common carotenes are alpha-carotene, beta-carotene and lycopene. Xanthophylls are yellow pigments that are oxygenated carotenoids. The oxygen atom helps in accepting or donating electrons. Zeaxanthin and lutein are typical xanthophylls.

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Who names hurricanes?

The process of naming hurricanes began in 1953, when the United States started using female names for hurricanes in the Atlantic Ocean. In 1978, both male and female names went into use for typhoons, or storms in the Pacific Ocean. In 1979, male names entered use for Atlantic storms as well.\nWith each successive storm, the list moves through the alphabet, so the first storm for a year would begin with the letter A, the second with the letter B and so on. Only 21 letters have enough names to work in the rotation, but if one season has more than 21 named hurricanes or tropical storms, the syste..

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Why are yeast colonies larger than bacterial colonies?

Yeast cells increase in number asexually by budding. As explained by Gary Kaiser at the Community College of Baltimore County, a bud forms on the outer surface of a parent cell, and the cell’s nucleus divides. One of the divided nuclei enters the forming bud, and cell wall material is produced between the parent cell and the bud. The bud breaks away to become a new daughter cell. This multiplication of genetically identical yeast cells populates into a colony. Bacteria divide and populate colonies via binary fission, another form of asexual reproduction. The circular DNA of the bacterium rep..

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What is the surface of the moon like?

The surface on the moon is covered in large plains of basaltic lava. Surface features such as small cones and volcanic domes, dark mantling deposits and sinuous rilles are also present on the moon's surface. The atmosphere on the moon is referred to as an exosphere, and is too weak and thin to support life.

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Why are red blood cells biconcave?

Because of their inability to reproduce themselves, red blood cells, or erythrocytes, must be produced by stem cells, according to Santa Barbara City College. These stem cells are located in bone marrow and are relatively undifferentiated. Their only role is to reproduce cells with very different properties from themselves. The same stem cells in bone marrow form all the blood cells, including the white blood cells and platelets. They produce more red blood cells than any other type by far, however, and red blood cells are the most numerous single type of cell in the body at any one time. The ..

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How do the ostrich and the gazelle benefit each other?

Ostriches and gazelles are each capable of identifying threats the other would not notice in time. Ostriches have acute eyesight, which helps make up for their poor hearing and sense of smell, and their height enables them to spot predators from afar.\nGazelles also have keen eyesight. However, since they're much shorter than ostriches, gazelles cannot see predators over tall grasses and shrubs. Gazelles hold up their end of their symbiotic relationships with ostriches by employing their keen senses of smell and hearing to detect threats. When an ostrich becomes alarmed after seeing a pre..

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What is an echogenic liver?

According to The Everett Clinic, fatty livers often produce these stronger than normal, or “echogenic,” echo returns. This occurs because the increased amount of fat around the liver increases the overall density of the organ enough to produce the relatively strong echo. However, a fatty liver cannot be positively diagnosed via an ultrasound, as the ultrasound does not measure the amount of fat in the liver.\nThe Everett Clinic states that a fatty liver occurs when the liver fails to store and burn fat in the right ratios. If more fat is stored than burned, fat can accumulate. This often c..

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What is a hypoplastic frontal sinus?

Sinus cavities are hollow areas in the skull found in the center of the forehead, in the cheekbones, behind the nose and between the eyes. These cavities are connected by a series of passageways and are lined with a soft, pink tissue. There are a total of eight sinus cavities, though some people are born with an extra one. Most of the sinus cavities drain mucus through the nose.\nAcute sinus infections can cause inflammation of the sinuses and increased mucus production. The inflammation blocks the nasal passages and keeps mucus from draining. This blockage leads to headaches and general disco..

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