Answer:
A
Explanation:
The possible number of amino acid residues in the peptide composed entirely of alpha-helical structure and found to contain an integer number of complete turns is 36
Answer:
Meiosis is the process of development of gamates in sexually reproducing organisms. Both males and females use meiosis to produce their gametes. In females the process of meiosis is called oogenesis as it produces oocytes which further develops into ova (eggs) and in males spermatogenesis takes place to produce sperms. Meiosis takes place in the germ cells of the organism. Meiosis is also known as reduction division as a diploid cell reduce to develop 4 haploid daughter cells. Prophase I is the initial phase of meiosis. This phase has six substages, therefore it requires more time to complete especially in oogenesis. During prophase I homologous chromosomes pair exchange their DNA this process results in chromosomal crossover. The new combination of DNA in the cross over chromosomes will be a source for genetic variations with production of new combination of allele. In metaphase I homologous pair of chromosome move together along a metaphase plate , microtubules emerge from the spindle and attach at the kinetochores near the centromere of each chromosomes. Microtubule from one side of the spindle attach to one of the chromosome in the homologous pair and that of other side attaches with other chromosome of each pair. Because of microtubules chromosome pair align at the metaphase plate (equator of the cell). The random alignment of chromosome pair at the equator plate will result in different proportion of transfer of genes from maternal and paternal chromosomes. This is the law of independent assortment, hence this will result in genetic diversity in the daughter cells.
Answer: have randomly arranged grains
include quartzite and marble
form from crystallized magma
Metamorphic rocks are those rocks that are modified by heat, pressure and chemical processes, that occurred on the rocks that are buried deep below the earth crust. The exposure of the rocks developing under the earth crust gets altered on the basis of the mineralogy, chemical composition of the rocks and the texture of the rocks.
The non- foliated rocks are type of metamorphic rocks, which are formed by the igenous intrusions. The minerals inside these rocks are formed by the crystallization of the magma, the atoms in these rocks are tightly packed, the external structure of the rocks do not show any kind of layering or band appearance. Therefore, the rocks exhibit randomly packed grains.
The examples of these rocks are hornfels, quartzite, marble and novaculite.
Answer:
Mass extinction occur when the environment is not favourable.
Explanation:
Mass extinctions occur on the earth when there is sudden change in the environmental conditions for an organisms that is not good for the survival of that particular organisms so they extinct from the earth surface. The example of mass extinctions are dinosaurs. These dinosaurs were extinct due to change in their environment that decreases the availability of food for them so due to no available food, the dinosaur extinct from the earth.
