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» Browse Science and Environment Term Papers
Mitochondria 2
Number of Words: 752 / Number of Pages: 3
... for providing the mitochondrion with a large surface area which enhances the productivity of respiration.
The inner membrane and outer membrane effectively divide the mitochondria into two internal compartments. The space located between the outer and inner mitochondrial membrane is called the intermembrane space. The space enclosed by the inner membrane is called the mitochondrial matrix. It is here that many of the metabolic steps of cellular respiration occur.
The intermembrane space reflects the solute composition of the cytosol, because the outer membrane is permeable to small solute molecu ...
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Essay On Evolution
Number of Words: 913 / Number of Pages: 4
... on the population. Another mechanism is gene flow which is
when a population may gain or lose alleles by the migration of fertile
individuals between populations. This may cause the allele frequencies in a gene
pool to change and allow the organism to evolve. The most obvious mechanism
would have to be mutation that arises in the gene pool of a population or
individual. It is also the original source of the genetic variation that serves
as raw material for natural selection.
Not only are there mechanisms of evolution, but there is also evidence
to prove that these mechanisms are valid and have he ...
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Albinism
Number of Words: 644 / Number of Pages: 3
... development. This can be inherited by an dominant or recessive trait. In complete , there is lack of pigmentation in skin and hair, as well as in retinal and iris tissue; in incomplete , skin and hair may vary from pale to normal; in ocular , function may vary from norma to impaired. Impairments may involve the retina and iris. If a person has then they usually have somewhere between 20/70 and 20/200 visual. Ty-Neg or also called type 1A results from a genetic defect in an enzyme called tyrosinase. Tyrosinase helps the body to change the amino acid tyrosine into pigment. An amino acid is a building b ...
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UFOs
Number of Words: 2685 / Number of Pages: 10
... " has been blamed for millions of
UFO governmental cover-ups around the nation. "Our problem is with government
secrecy, because it widens the gap between citizens and the government,
making it much more difficult to participate in the democratic process
(Stacey 40)," says Steven Aftergood while addressing UFO secrecy. The UFO
enigma, or as it is formerly know as the "'Cosmic Watergate' : the ongoing
cover-up of the government's knowledge about extraterrestrial UFOs and their
terrestrial activities (Stacey 36)" is believed to be started during the
Nixon administration, which is still under alot of scru ...
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Dreams Rem
Number of Words: 713 / Number of Pages: 3
... theory and how the mind works while asleep. In 1953 sleep researchers led by Nathaniel Kleitman made the important discovery of rapid eye movement--or REM-- sleep. Curious about the long-standing observation that the eyeballs of sleeping subjects in both humans and animals periodically move during sleep, they connected laboratory subjects to equipment that measured their brain waves, muscle tone, and eye movement. About 90% of the time when subjects were awakened during REM sleep, they reported a dream.
Prior to laboratory REM research, it was unknown how frequently Humans dreamed. Some theori ...
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Mutations
Number of Words: 733 / Number of Pages: 3
... codon consists of a sequence of three bases--for example, GAG or TCA. The four bases can be assembled into 64 possible codons. Because proteins are built from only 20 amino acids, most amino acids are specified by more than one codon.
occur when one base is substituted for another or when one or more bases are inserted or deleted from a gene. Substitution affect only one codon, and in most cases the effect is minimal. One reason is the redundancy of the genetic code mentioned above. Because many codons mean the same thing, the altered codon might still specify the same amino acid. Furthermore, even ...
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Big Bang Theory
Number of Words: 1285 / Number of Pages: 5
... was no beginning in the past, nor will there be
change in the future. This model assumes the perfect cosmological
principle. This principle says that the universe is the same everywhere
on the large scale, at all times.2 It maintains the same average density
of matter forever.
There are observational evidences found that can prove the Big Bang
model is more reasonable than the Steady State model. First, the
redshifts of distant galaxies. Redshift is a Doppler effect which states
that if a galaxy is moving away, the spectral line of that galaxy observed
will have a shift to the red end. The ...
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Plant Breeding
Number of Words: 622 / Number of Pages: 3
... breeders, because
they can often produce fertile varieties - indeed, new species - by
crossbreeding between species. This is because hybrids are often polypoid.
Polyploidy, as we know, can occur naturally in the wild. Some species of
cotton that we grow are polypodies that probably arose originally by
accidental crosses between different species of cotton.
But breeders do not have to rely on accidents. They can attempt to
produce fertile polypodies by crossbreeding between different species. One
early attempt to produce another hybrid species was made in 1927 by the
Russian geneticist G. ...
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Internet The Advantages And Disadvantages
Number of Words: 2517 / Number of Pages: 10
... to be aware of its advantages as well as disadvantages.
While seemingly high tech the Internet concept is rather simple. Computers speak to one another and send information. This is accomplished by sending and receiving electronic impulse, and then decoding them into a message. In order to communicate with one another they are linked up in a network. They are then able to access information from thousands of other computers. The network acts like one large computer storing information in various places, rather than in one physical structure. Users tap into the Internet to access or provide informati ...
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Hypotheses Of The Effects Of Wolf Predation
Number of Words: 1767 / Number of Pages: 7
... the effects
of these predator-prey interactions requires studies of a long duration, and
statistical analysis of large data sets representative of the populations as a
whole. Predation could limit the prey distribution and decrease abundance. Such
limitation may be desirable in the case of pest species, or undesirable to some
individuals as with game animals or endangered species. Predation may also act
as a major selective force. The effects of predator prey coevolution can explain
many evolutionary adaptations in both predator and prey species.
The effects of wolf predation on species of large ung ...
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