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In music, a half note (American) or minim (British) is a note played for half the duration of a whole note (or semibreve) and twice the duration of a quarter note (or crotchet). In time signatures with a denominator of 4, such as 4/4 or 3/4 time, the half note is two beats long.
Half notes are notated with a hollow oval note head (like a whole note) and a straight note stem with no flags (like a quarter note; see Figure 1). The halfrest(or minim rest) denotes a silence for the same duration. Half rests are drawn as filled-in rectangles sitting on top of the middle line of themusical staff. As with all notes with stems, half notes are drawn with stems to the right of the notehead, facing up, when they are below the middle line of the staff. When they are on or above the middle line, they are drawn with stems on the left of the note head, facing down.
The note derives from the minima in mensural notation, which is Latin for 'least or smallest,' because at one stage it was the shortest of all note values used. The word minim comes from this name. The American term half note is a 19th-century loan translation of German Halbe Note.
The names of this note (and rest) in other languages vary greatly:
The French and Spanish names for the note (all meaning "white") derive from the fact that the minima was the shortest unfilled note in mensural white notation, which is true as well of the modern form. The form in the earlier black notation resembles the modern quarter note (crotchet). The Greek and Chinese names mean "half" and in Greek, both the modern word (miso - Î¼Î¹ÏƒÏŒ) and the older (imisi - Î®Î¼Î¹ÏƒÎ¹) are used. For the rest, the word "pafsi" (Ï€Î±Ï�ÏƒÎ·) is used; this means "pause".
In biology, fission is the subdivision of a body, population, or species into parts and the regeneration of those parts into separate individuals. Binary fission, or prokaryotic fission, is a form of asexual reproduction and cell division used by all prokaryotes, some protozoa, and some organelles within eukaryotic organisms. This process results in the reproduction of a living prokaryotic cell by division into two parts that each have the potential to grow to the size of the original cell.
Mitosis and cytokinesis are not the same as binary fission. To be specific, binary fission cannot be divided into prophase, metaphase, anaphase, and telophase because prokaryotes have no nucleus and no centromeres. The ability of some multicellular animals, such as echinoderms and flatworms, to regenerate two whole organisms after having been cut in half, is also not the same as binary fission. Neither is vegetative reproduction of plants.
Binary fission begins with DNA replication. DNA replication starts from an origin of replication, which opens up into a replication bubble (note: prokaryotic DNA replication usually has only 1 origin of replication, whereas eukaryotes have multiple origins of replication). The replication bubble separates the DNA double strand, with each strand acting as template for synthesis of a daughter strand by semiconservative replication, until the entire prokaryotic DNA is duplicated.
Cell division in bacteria is controlled by the FtsZ, a collection of about a dozen proteins that collect around the site of division. There, they direct assembly of the division septum. The cell wall and plasma membrane starts growing transversely from near the middle of the dividing cell. This separates the parent cell into two nearly equal daughter cells, each having a nuclear body.
The cell membrane then invaginates (grows inward) and splits the cell into two daughter cells, separated by a newly grown cell plate.
Use by eukaryotic organelles
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Answers:1. endoplasmic reticulum contains ribosomes where the translation (code in the transfer RNA is translated to amino acid chains ultimately forming protein) takes place. 2. Binocular vision is 2 dimensional. The stereovision is 3 dimentional and can perceive depth which is present only in human beings. all other animal have binocuolar vision in certain angles where the visual fields of both the eyes overlap. 3. Spinal nerves and cranial nerves are part of peripheral nervous system; while brain and spinal cord belong to central nervous system 4. By enzymatic conversion, by uptake by the hepatocytes (e.g.alcohol) , phagocytosis by Kupfer cells.
Answers:1. mutation 2.probability 3.replication 4.incomplete dominence 5.trait 6.idk sorry 7.hybrid 8.phenotype... but thats only eight letters... 9.chromosomes 10.genetics 11.allele 12.DNA 13.idk sorry 14.genes 15.meiosis I hope this helps
Answers:Charophyceans ---> bryophytes ---> pteridophytes ---> gymnosperms ---> angiosperms. Charophyceans: algae In the water, algae were supported. Every cell had contact with the ocean, which brought water and nourishment that could be absorbed through the cell wall. Reproduction was simple: algae released their eggs and sperm cells into the water where they could meet and form tough little capsules called zoospores. On land, all this changed. Algae cast up on the sea shore or trapped in evaporating ponds were subjected to drying winds and often to large temperature swings. At first they probably just died, but over millions of years a few algae were able to resist short periods of dryness and live on. These became the ancestors of our land plants. Bryophytes: mosses They form low mats, and the little plants, grouped tightly together, can absorb water like sponges. They do not have roots, although a cell at the bottom of each sprig forms a rhizoid that clings to rocks and other surfaces. Mosses do not have vascular structures (tubes like our veins for moving fluids around inside themselves) , but they do have an effective method of reproduction called alternation of generations. This method protects and nurtures the vulnerable zygote. A zygote is the new cell that is produced by the union of the genetic material from two parents. It is the cell from which a new and unique organism will grow. Mosses found a way to keep the zygote moist and alive. The zygote grows into a structure that makes spores, and the tiny spores float away in the air. Pteridophytes: Ferns Ferns are the plants that developed vascular systems. Some ferns still have rhizoids, but they also have roots. This makes it possible for ferns to grow into large plants. Ferns do not have true seeds. They reproduce by alternation of generations. When you turn fern fronds over, you can often see little dots on the underside. These dots are groups of spores. When the dots are brown, the spores are getting ripe and will soon be released from the plant. Spores are tiny, and will float away in the air. Some of them will come down in a new place that is favorable for fern growth. Gymnosperms: naked seed The first seed-bearing plants are called gymnosperms. Gymnosperm means "naked seed" because these seeds have only a dry, thin covering instead of a sturdy protective seed coat.One important change was the development of pollen to replace the swimming sperm. Pollen could float on the wind and was not damaged by the dry air. The plants made pollen cones (see picture above) which made only pollen and small, tough woody cones in which the female half of the process could be protected. (See picture with blue-green cones here.) The pollen fell on these woody cones and grew tubes down to find the ovules (eggs). After the eggs were fertilized, they developed and matured in the cone. The seed that resulted could survive drought in a dormant state. It could wait for a favorable season to begin its growth. It had a package of food to draw on when it germinated. These seeds were well adapted to the land. Angiosperms: flowering seed About a hundred and thirty million years ago, a new kind of plant appeared. This plant developed two innovations. First, the new plants produced flowers. Flowers allowed the plants to form partnerships with insects, and insects, in exchange for pollen and nectar, greatly increased the efficiency of the plants' pollination.Second, the parent plant provided a protective covering for the seed. Sometimes this covering took the form of a burr or a fruit, which improved the dispersal of the seeds to other places.
Answers:My only quibble would be with #1, I would have chosen A, raw materials rather than D, information, but from your notes in class you would probably know better what answer the teacher wants. I couldn't choose an answer for #16 for obvious reasons. #17 was worded in a tricky way, but I agree with your answer since genes code for proteins, ribosomal RNA and transfer RNA so that the statement "genes produce instructions only for making proteins" is correct. #20 should be A, bacterium, since photosynthesis, DNA transfer and motility all arose in single-celled organisms prior to the appearance of multicellular organisms, but again from your notes in class you will have a good idea of what the teacher is looking for and my interpretation of the question could be incorrect. All of the rest of the answers look fine.