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Here you arehttp://www.s-cool.co.uk/gcse/chemistry/chemical-bonding
There is an image herehttp://www.s-cool.co.uk/a-level/biology/nervous-and-hormonal-control/rev...
We can put neurones into three groups on the basis of what they do:
1 sensory neurones Carries impulses from receptors to the CNS.
2 motor neurones Carries impulses from the CNS to the effector.
3 relay neurones Co-ordinate the response. Are link neurones in the CNS.
Sensory neurons have longer dendrites & shorter axons.they carry impulses from sensory organs to spinal cord/brain.
motor neurons have longer axons & shorter dendrites.they carry impulses from spinal cord/brain to the effector organs.
Receptors are cells that detect stimuli - for example, heat, pressure, light.
Sensory neurones bring impulses from receptors to the central nervous system (CNS). These are very long cells as they have to carry the impulse from the body to the place where the response is managed.
From there, the impulse may pass on to a motor neurone to be taken to a muscle or gland (the effector).
Sometimes there is an intermediate neurone (also known as a 'relay' neurone) within the CNS linking the sensory neurone with the motor neurone.
I need solutions of addendum exercises of D4.
I wanna an analysis on the drama
To read the table for data (initially) you simply read along the rows or the columns to find out the answer.
To then use that for probability, what you need to do is take your answer (found using the above method) and work it out as a percentage of all the answers in that row or column.
So its hard to draw a table here but imagine that this is a table listing boys and girls in year 10 and in year 11. (So the rows are boys and girls, the columns are Y10 and Y11. The numbers in the table are the no of boys and girls in each year
Boys - 100 in Y10 ; 150 in Y11
Girls - 80 in Y10 ; 120 in Y11
QUESTION - If you picked a girls at random, what is the probability that she is in Y 10?
There are 80 girls in Y10 (by reading along the girls row in the table).
And there are a total of 80 + 120 girls in total in Y 10 and 11 = 200 girls
So the chance you get a Y 10 girl is 80 / 200 = 2 / 5 = 0.4 or 40%
Have a look herehttp://www.s-cool.co.uk/gcse/physics/properties-of-waves/revise-it/refle...
I found this but you need to make sure that you only learn the ones that are on your specification or you will waste a lot of time and effort
alternate forms or varieties of a gene. The alleles for a trait occupy the same locus or position on homologous chromosomes and thus govern the same trait.
organic molecules that are building block of proteins. There are 20 different kinds of amino acids in living things. Proteins are composed of different combinations of amino acids assembled in chain-like molecules during the process of protein synthesis.
thread-like, gene-carrying bodies in the cell nucleus. They are visible only under magnification during certain stages of cell division. Humans have 46 chromosomes in each somatic cell and 23 in each sex cell.
a sequence of three nucleotide bases in RNA that codes for a specific amino acid.
the exchange of genetic material between homologous chromosomes in meiosis. This result in gametes with greater genetic diversity. Specifically, a portion of a chromosome is broken and reattached on another chromosome. Also referred to as Recombination.
DNA (deoxyribonucleic acid):
a large organic molecule that stores the genetic code. DNA id composed of sugars, phosphates and bases arranged in a double helix shaped molecular structure. Segments of DNA in chromosomes correspond to specific genes.
an allele that masks the presence of a recessive allele.
the twisted ladder shapes that is characteristic of DNA molecules
multicelluar organisms (contrasted with prokaryotic or single-celled organisms)
genetic change in a population of organisms that occurs over time.
a coding region of DNA. They are transcribed to the final mRNA molecule (contrasted with introns which are non-coding regions that are spliced out from the tRNA molecule)
a small population effect in which the genes of a few people (the population founders) are inherited over time by a large number of descendants.
sex cells: sperm or unfertilized egg cells produced in the testes and ovaries of animals. Gametes are produced by meiosis. They have half the number of chromosomes found in somatic cells.
units of inheritance usually occurring at specific location, or loci, on a chromosome. A gene may be made up of hundreds of thousands of DNA bases. Genes are responsible for hereditary characteristics.
the transference of genes from one population to another, usually as a result of migration. The loss or addition of individuals can change the gene frequencies of both the recipient and donor populations.
all of the genes in all of the individuals in a breeding population.
random changes in gene frequencies resulting from chance. Genetic drift occurs in small populations.
the genetic makeup of an individual. Genotype can refer to an organism's entire genetic makeup or the alleles at a particular locus.
the percentage of phenotypic variation attributable to genotypic variation.
a genotype consisting of two different alleles of a gene for a particular trait (Tt).
genes involved in the regulation of development. A type of regulatory gene
chromosomes that are paired during meiosis. Such chromosomes are alike with regard to size and also position of the centromere. They also have the same loci coding for the same traits.
having the same allele at the same locus on both members of a pair of homologous chromosomes. An individual may be homozygous dominant (TT) or homozygous recessive (tt).
major evolutionary changes in a population's gene pool, occurring over many generations, resulting in the development of new species.
cell division in specialized tissues of ovaries and testes, which results in the production of gametes. Meiosis involves two divisions and results in four daughter cells, each containing only half the original number of chromosomes—23 in the case of humans.
changes in gene frequencies from one generation to the next. The accumulation of micro evolutionary change can result in macroevolution.
the simple cell division process that occurs in somatic cells. One cell divides into two offspring cells that are identical to each other in chromosome complement
an alteration of genetic material such that a new variation is produced. For instance, a trait that has only one allele (A) can mutate to a new form (a). This is the only mechanism to produce NEW variation. There are numerous types of mutations, including point mutations, "silent" mutations and chromosomal mutations,
an evolutionary mechanism that occurs when some individuals of a population are better able to adapt to their environment and subsequently, produce more offspring. Differential reproductive success between individuals is the key. Those who produce more offspring have a greater influence on the gene frequencies of the next generation.
mate selection based on one or more traits that are discriminated for or against. This is a mechanism of evolution. Includes positive and negative.
the basic building block of DNA and RNA. It consists of any one of four bases attached to a sugar and phosphate.
the observable or detectable characteristics of an individual organism: the physical expression of a genotype.
a more or less distinct group of individuals within a species who tend to restrict their mate selection to members of their group. Members of a population tend to have similar genetic characteristics due to generations of interbreeding.
any of a large number of complex organic molecules that are composed of one or more chains of amino acids. Proteins serve a wide variety of functions. Proteins may be enzymes, hormones, antibodies, structural components, or gas-transporting molecules.
shuffling of chromosomal alleles during the process of meiosis
an allele that is masked in the phenotype by the presence of a dominant allele. Recessive alleles are expressed in the phenotype when the genotype is homozygous recessive (tt).
RNA (ribonucleic acid)
a type of nucleic acid that is found in both the nucleus and the cytoplasm of cells. Unlike DNA, RNA is single stranded. Messenger RNA (mRNA) carries the genetic code from the DNA and translates it with the help of transfer RNA (tRNA) at the site of the ribosomes in the cytoplasm in order to synthesize proteins.
the evolution of new species from older ones.
a natural population of organisms that can interbreed to produce fertile offspring. Members of one species are reproductively isolated from members of all other species (i.e., they cannot mate with them to produce fertile offspring)
River was made deeper and wider to let more water through
The surrounding area and car park were raised
A bridge and other buildings were replaced - I assume that the design and construction were specifically to chosen in the light of this potentially happening again.
More stations where water flow was measured were set up
What's the question?