Answer:
the correct answers are as follows
12:
b. Testcross- an organism with dominant phenotype but unknown genotype is crossed with homozygous recessive organism for the same trait. Based on the results obtained, if all offsprings have the same phenotype, then the parent is homozygous, but when a 1:1 ratio is observed in the offsprings, then the parent is heterozygous.
13.
e. Watson and Crick- they both used the crystallographic images from Franklin, analyzed them to first elucidate the 3D structure of the DNA and propose it to the world.
14.
c. Intracellular and commonly found in the cytoplasm- the receptors of steroid hormones are generally present within the target cell either in the cytoplasm or nucleus, since they alter gene expression.
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e. Certain prokaryotes/bacteria- this is a process that will enable disease-causing pathogens to communicate and cooperate with their group, by the release of autoinducers that increase their cell density.
Recombination is the method by which organisms can randomly assort their genotypes amongst each other to create offspring with a different haplotype than either of its parents. This can be done by either copying sequences from one homologous chromosome to another (no physical exchange) or crossing over (physical exchange.
Crossing over is a mechanism in eukaryotes by which recombination can occur, in which the two homologous chromosomes contributed by both parents literally cross over and break at certain points to exchange certain sections of the chromosomes amongst each together.
Self fertilizing organisms typically do not produce offspring that are genetically identical. However, this has an inbreeding effect on its offspring, since it is recombining from the same genotype and so has a higher chance of producing homozygous offspring. This is very detrimental for mammals and some eukaryotes, but in some other organisms such as bacteria, homozygosity is typically not an issue.
Answer:
Internal factors include particle-size distribution, organic matter content, mineralogy and water content of the soil. Externally applied forces are generally mechanically applied forces, the primary source of these being vehicular traffic
Explanation:
The main purpose is protection. The lipid bilayer protects the cell from viruses and other threats to the cell. It also maintains homeostasis within the cell by monitoring the amount of substances the enter or exit the cell.
Tundra
Tundra is a biome that is located in the coldest regions of the world. This is characterized by short growing seasons and low temperatures. The plants growing in these regions are short perennials.
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