Plants such as the cactus reside in the desert biome.
Answer:
B. the appearance of lichens and mosses in an area where a glacier has recently melted away
Explanation:
Ecological succession, which refers to the series of changes that occurs over time in an ecosystem, can be of two types namely: primary succession and secondary succession.
Primary succession is a succession that involves an area where no form of life has grown previously, hence, the area of land is barren e.g bare rock. Primary succession is first colonized by species called PIONEER SPECIES e.g. lichens, mosses etc.
According to this question, "the appearance of lichens and mosses (pioneer species) in an area where a glacier has recently melted away" is an example of PRIMARY SUCCESSION.
Answer:
a. and e.
Explanation:
Metabolic alkalosis would cause slower and shallower breathing which increase carbon dioxide concentrations which in turn are consumed to form carbonic acid which helps decrease the pH.
Answer:
B. Use the polymerase chain reaction (PCR) to make multiple copies of the DNA.
Explanation:
The scientist is to analyze a small sample of DNA, the most useful step to start this would be first the use of polymerase chain reaction to make various copies of that DNA sample. PCR is essential and quick process that gives a lot of copies within few hours. It uses the sample or target DNA, according to which the primers are designed. Taq polymerase and DNA polymerase are also used in the process, it consist of various cycles in which copies are made. There are three basic steps 'Denaturation', 'annealing', and 'extension'.
Answer:
Egg and sperm cells have to have half the number of chromosomes as in body cells so when they combine to form a zygote, the zygote is diploid and has the correct number of chromosomes. This explanation describes why meiosis produces haploid cells.
Explanation:
Meiosis is a type of cell division in which four haploid cells are produced from a diploid parent cell having two copies of each chromosome, where the number of chromosomes in the parent cell is reduced to half by undergoing DNA replication and nuclear division. Diploid cell contains two copies of each chromosome, one inherited from mother and the other from father while haploid cell contains only one copy of each chromosome. Examples of diploid cells (somatic cells) are skin, blood, muscle cells etc. Eggs or ovum (female gametes) and sperm (male gametes) are haploid reproductive cells. If the total number of chromosomes in a diploid cell is represented as '2n', then the number of chromosomes in a haploid cell is 'n'. During the fertilization process in an organism, the correct number of chromosomes is restored when the haploid male and female gamete combined to form a single diploid zygote, which is the first developmental stage of an organism.
