Answer:
Crossing-over between homologous chromosomes (prophase 1), the random lining of homologous chromosomes (metaphase 1), and random fertilization are the mechanisms involved in genetic variation.
Explanation:
Crossing-over between homologous chromosomes (prophase 1), the random lining of homologous chromosomes (metaphase 1), and random fertilization are the mechanisms involved in genetic variation.
The Crossing-over events occur between two homologous chromosomes in the equatorial plane and make the daughter cells genetically different from the original one. The Chiasma is the position where two homologous chromatids interchange genetic information, giving a place for new genetic material or information to be provided to descendants. After crossing over, homologous chromosomes get separated again.
On the equatorial plane, homologous paired together, randomly aline with their kinetochores facing opposite poles. The random arrangement of tetrads is different in every cell going through the meiosis process. There is no equal alinement between two cells. When tetrads aline in the equatorial plane, there is no predetermined order for each of the homologous chromosomes of each tetrad to face one of the poles and then migrate to it while separating. Chromosomes of the homologous pair arrange to face any of the poles to migrate forward to it. Each of the chromosomes has two possibilities for orientation at the plane. When the new haploid cells are formed, the number of variations in each cell is also different and depends on the chromosomes that form that cell. The order in the equatorial plane is what introduces variation into the gametes, being almost impossible for two gametes to have the same genetic charge.
Independent assortment occurs when the alleles from two or more different genes distribute in gametes independently from each other. In other words, a gamete receives an allele from a gene that does not depend on nor influence the allele of another gene in the same gamete. This can only be applied to independent genes. An organism gets only one of the members of the chromatids pair of each parent.
An abundance of biodiversity:)
Let's say a geographical barrier separates a species into two different population. Which also cause a reproductive isolation ( the two pupolations cannot interbred)
Throughout the time (lets say a million years), the two populations will undergo a lot of changes in their respective genomes and eventually will form 2 different species.
If there is no reproductive isolation, the 2 population could interbred with one another and there will be no speciation
Answer: 2, 4 and 5.
Explanation:
Human system are made of various organs which in turn are made up of various tissues which in turn are made up of various cells. Cells are therefore much more numerous than systems.
As already mentioned, organs are made up of tissues which are made up of cells so statement 4 is right.
As systems are made up of various organs working together, they are more complex than the individual organs. For instance, the Muscular system is more complex than the triceps or bicep muscles.
Answer:
The speed of the light waves will decrease