Answer:
Convergent evolution
Explanation:
The convergent evolution is a very interesting evolutionary process that is also very helpful when ti comes to explaining how the evolution actually works. This type of evolution appears when two or more different species, be it plants or animals, live in places that are isolated from one another, but have the same or very similar living conditions. The species then evolve in a very similar manner despite them not being closely related at all, bu the response from them is the same in order to survive in the environments that provide the same conditions. If the conditions are very harsh, hot, and dry, thus a desert, then the two plants will develop the same or very similar features. They will have very hard leaves that stop the loss of water. The amount of leaves will be very low. The root systems will be disproportionately large. They will both have the ability to extract humidity from the air. The chances are also very high that they will both have thorns for protection, as well as certain amount of poison in them for the same purpose.
Answer:
Many human and physical factors affect population distribution and population density across the world. Physical factors that affect population density include water supply, climate, relief (shape of the land), vegetation, soils and availability of natural resources and energy.
The phenotype of antenna in crawfish depends on the protein amount in the antenna length. The offspring have different phenotype than their parent because of the amount of protein translated from each parent gene is determining in this.
The gene determines the amount of protein to be present in the antenna to determine its length.
Explanation:
Data given:
Two crawfish parent = medium length antennae, genotyoe Ll
One offspring = short antenna, genotype ll
one offspring = long antennae, genotype LL
The traits in offspring is shown as:
L l
L LL Ll
l Ll ll
The proportion of allele present in the gene determined the length of the antenna in crawfish.
The difference in length of the antenna in crawfish is due to the amount of protein for the phenotype present in the individual. The amount of protein to be expressed in the crawfish is given by both the parents. The tendency of protein expresed define the phenotype of antenna length.
Answer:
Amniocentesis is an invasive method that involves the aspiration of 10-20 ml of fetal water through the abdominal wall under ultrasound-guided control. In most cases, the procedure is performed around the 16th week of gestation. The fetal water sample contains fetal cells, mostly cells of fetal skin and the epithelium of the urinary tract.
Chorionic Villus Sampling (CVS) biopsy is performed between weeks 11 and 12 of gestation. During biopsy, with ultrasound guidance, the tissue of the chorionic fossa is aspirated mainly across the abdomen (transabdominal pathway). The biopsy specimen is of fetal origin and belongs to the outer layer of blastocyst cells or the trophoblast (outer layer of the placenta). Very often, the biopsy specimen contains tissue of the decidua (mucous membrane of the uterus) that is of maternal origin, and it is necessary to remove the maternal tissue before any treatment of the sample.
Explanation:
The amniocentesis procedure carries a risk of miscarriage of 0.5-1%. After aspiration of the fruit of the water, the sample is centrifuged to separate the cells from the amniotic fluid. Separate cells are seeded on a nutrient medium (cell culture) that stimulates cell growth. After about 14 days, the cell culture is further used for various genetic or biochemical analyzes such as karyotyping.
The advantage of chorionic biopsy is the amount of biological material, which is sufficient for the whole a number of different laboratory procedures. Also, a great advantage is the timing of the procedure as it allows diagnosis in the first trimester of pregnancy, but the chorionic biopsy procedure itself carries a risk of miscarriage of 1-2%.
