Sexual reproduction allows some of the genetic material from the father and mother to mix producing offsprings that are not identical but resemble the parents in certain charateristics. This combination of genetic material from the father and mother results in the variation of offsprings.
Aside from mutation the sexually reproducing variation is due to independent orientation of chromosomes in meiosis ( two ways the sister chromatids can line up in their tetrads ), crossing over ( non-sister chromatids exchanging sections of genetic material ) and random fertilization in which male and female gametes randomly come together to form zygotes.
There are many reasons. First of all, each parent has two sets of alleles for every gene they have. In the parent, generally, only the dominant gene persists. But when their gametes (sperm/egg) are formed during meiosis only one allele goes to each gamete. So, a gene that was recessive in the father might manifest in the child if the mother also contributes the same recessive gene or a gene that is more recessive than the one the father contributes. Furthermore, during meiosis, alleles line up in there respective chromatids and "crossing over" occurs. Crossing over is basically the trading of alleles from one chromatid to an adjacent chromatid and results in a chromosome that is unique from that of the parent making the contribution. Furthermore, mutations in the gametes can cause additional variation. Inconsistencies with meiosis such as non-disjunction (a case where each gamete does not receive equal genetic material) can result in problems such as Down syndrome or the much less dramatic Turner syndrome, etc.
Human recombination is a significant source of genetic variation.
recombination of alleles
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Purebred organisms are the organisms in the off springs for many generations which have the same traitA true-breeding organism, sometimes also called a purebred, is an organism that always passes down certain phenotypic traits (i.e. physically expressed traits) to its offspring.
Chemosynthetic organisms obtain their energy directly from raw chemicals in their environment. Examples of this include tubeworms living next to hydrothermal vents.
heterotroph
Every organism: directly and indirectly (plants etc.)
Effort To Reproduce Organisms In The Labratory(:
Reproductive variation is central to evolution. All else in evolutionary theory follows directly or indirectly from the fact that organisms reproduce with variation.
a varies directly as b and a = 12 when b = 4. What is the constant of variation?
what is an organisms that use sunlight directly to make sugar
DNA Replication
Algae
a is directly proportinal or inversely proportional to b
Momentum is directly proportional to the mass.
A variable y is said to be in direct variation with a variable x if there is a constant c (>0) such that y = c*x. c is called the constant of direct variation or proportionality.
plants
Both are variations of certain kinds of equations. X=kY is a direct variation since X varies directly as Y and k is the constant of variation. X=k/Y is an inverse variation where X varies inversly as Y and k is the constant of variation. Both of these variations are also functions.
pi
Direct variation refers to two variable quantities have a constant (unchanged) ratio, in which a variable "varies directly with the other."In order to have a direct variation, the constant of variation must be not equal to 0 in the equation y=kx, where k is the constant.When you try to put 2x+3y=0 into that formula (y= form), you get:2x+3y=03y=-2x ;Subtract the 2xy=(-2/3)x ;Divide by 3Your constant of variation is -2/3, and since it is less than 0, it is does variate directly. Therefore, y varies directly as x.