"Futabasaurus" is the first elasmosaurid found in Japan. The type species is "F. suzukii". Many of the bones of the type specimen show apparent scavenging or predation by sharks.
Ovum
An ovum (Latin: "egg", plural: ova) is the name for the haploid female reproductive cell, or gamete. Both animals and land plants (embryophytes) produce ova.
Ova are made and released by a female's ovaries. At birth, a female has all of her eggs, and from puberty, she releases an egg once a month until none are left. This is called oogenesis.
When the ovum is fertilised by a male's sperm, it becomes a zygote, which develops into a new organism. The ovum is fertilized inside the female body, and the embryo then develops inside the uterus, being fed by the mothers placenta.
The ovum is the largest cell in the human body. You can see it without a microscope. The human ovum is between 100 and 200 µm long. They are nevertheless much smaller than the cleidoic eggs laid externally by reptiles and birds, which is why they need a long period of internal development in the womb.
The sexual cycle is quite different in other mammals, whose females are only receptive during the 'heat' part of their estrous cycle when eggs are released from the ovary. Sexual activity then continues for a few days, then ceases entirely until the next heat.
In many plants, ova are made inside archegonia through meiosis. The archegonium has a long 'neck' with the egg cell inside. When the egg is mature, the neck opens and sperm swims in to fertilize the egg.
In flowering plants, the female gametes are made of only eight cells, called the embryo sac, inside the ovule. The cell closest to the opening of the embryo sac becomes the egg cell. When pollinated, sperm swims into the embryo sac and fertilizes the egg. The zygote then develops into an embryo inside the ovule.
Ovule
Ovules produce the female reproductive cells which get fertilized during sexual reproduction in seed plants. The word literally means "small egg."
The megagametophyte (also called the "embryo sac" in flowering plants) is inside the ovule. The megagametophyte produces the egg cell.
Horn (musical instrument)
The horn is a brass instrument. It developed from the horns that some animals have on their heads. Modern horns are often called French horns.
Horns were often used during hunting. These early brass instruments were round so that the hunter could put his arm through it and carry it on his shoulder and blow it while riding a horse. The riders could send messages to one another by blowing particular notes.
In the 17th century the modern orchestra was developing. Orchestras played for operas. Opera stories in those days were usually about gods and goddesses or kings and queens. There was often a hunting scene in the story. Hunters were asked to come and play their horns in the orchestra for these scenes. This is how the horn became an orchestral instrument.
A brass instrument gives one basic note. Changing the pressure with the lips produces a few other notes. Gradually horn players discovered that if they put their right hand in the bell they could change the basic note. This made it possible to play lots of different notes. When Mozart wrote his horn concertos he was writing for a hand horn. When a note is played using the hand in the bell it makes the note sound different: more muffled (a bit like speaking while covering your mouth with your hand). A Mozart horn concerto sounds very different when played on a modern horn.
Another way to change the notes on a horn was to use crooks. These are like extensions to the horn. The longer the tube the lower the note, so adding a crook (an extra circle) would give a lower basic note.
By the 1830s the modern horn with three valves had been invented. These valves change the length of the tube, so that the horn had now become chromatic i.e. it could play all the notes including sharps and flats. Composers like Richard Wagner and Richard Strauss wrote complicated music for the horn which would never have been possible on the natural, valveless instruments. However, some composers preferred the sound of the natural horn. Brahms wrote for the natural horn when he wrote his "Horn Trio" for piano, violin and horn. Benjamin Britten, in his "Serenade for tenor, horn and strings", asks for the horn to played naturally (without valves) for the fanfare at the beginning to make it sound like a hunting horn.
The horn has a conical bore. This means that the tubing gradually becomes wider (a trumpet and trombone have a cylindrical bore): the tubing is the same thickness all the way along. The modern horn has 6.4 metres of tubing. It makes a beautiful, warm sound, but it is quite hard to play because the mouthpiece is small and the harmonics (the notes that can be played by changing the lip pressure) are very close together. The horn is a transposing instrument, usually in F (a written C sounds like the F below).
At the end of the 19th century the so-called “double horn” was invented, which was like a combination of a horn in F and a horn in B flat.
In the 18th century there were generally two horns in an orchestra. This became three or four in the 19th century, and some large orchestras now may have up to eight horns.
Valhalla
In Norse mythology, Valhalla (Old Norse: "Valhöll" - “hall of the slain”) is an enormous and majestic hall in Asgard, headed by Odin. Described as a "warrior's paradise," it is here that the souls of those who are slain in battle go, chosen and guided by the Valkyries, a group of warrior maidens in service to Odin. Once they are there, these eïnherjar, as they are known, make revelry, as they feast on the beast known as Sæhrímnir, having their fill of mead made from the udders of the female goat Heiðrún. The feast is prepared by Andhrímnir (Old Norse: “the one exposed to soot”), the cook of the gods, in his cauldron, Eldhrímnir (Old Norse: “fire-sooty”). Outside of Valhalla’s doors lies Glasir (Old Norse: “gleaming”), a massive tree that grows golden leaves, while its ceiling is adorned with golden shields. The tree Læraðr stands atop the great hall, where both Heiðrún and the stag Eikþyrnir (Old Norse: “oak-thorny”) graze its foliage. During Ragnarök, the eïnherjar will aid Odin in his battle against Surtr and his forces.
Horn (anatomy)
Horns are part of the body of some animals. They grow on the animal's head. They are projections (things that stick out) made of hard skin. The horn has a lot of keratin in it, the same protein that is in human hair and nails.
Normally horned animals will have two horns, but the rhinoceros has just one horn in the middle of its head.
Animals often use their horns for fighting one another.
Thousands of years ago people used the horns of dead animals for musical instruments (see horn (postal horn)). In later times, they were used for carrying gunpowder.
Mead
Mead is a fermented alcoholic drink. It is made from honey. Its history is possibly as old as that of beer. It is made by mixing honey, water, and yeast. Some kinds of mead also include spices or fruit. Mead is sometimes called "honey wine".
Archaeologists discovered that people made mead 9,000 years ago. Mead was described in the Rigveda, which is a Hindu religious text. Mead is popular in Central Europe and the Balkans. Mead is also made in Ethiopia and South Africa.
Ull
In Norse mythology, Ull (or Ullr or Uller) is the son of Sif, and the stepson of Thor. He is thought to be the god of Winter, of hunting, of hand-to-hand combat, and of the willow tree. His name means "glory". He was said to be a great archer and skier who left blazing trails across the sky.
For this reason he is celebrated in modern times as the god of skiing. His name is used as a name for ski lodges like the House of Ullr at Thredbo, New South Wales. ULLR Labs make smartphone applications to help people avoid avalanches.
Thrud