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%.
Modern humans have been the only species of homo, so true .
Show how little things make up bigger things and a microscope or images of microscopic things.
Answer:
The possible blood types of their children are: type AB (iAiB), type A (iAi), type B (iBi), type O (ii)
Explanation:
Blood type in humans is controlled by a gene with multiple alleles. Alleles iA and iB are dominant over allele i but co-dominant. The following blood types are encoded by the following alleles:
Blood type AB - iAiB
Blood type A - iAiA or iAi
Blood type B - iBiB or iBi
Blood type O - ii
According to this question, a man who has type B blood has children with a woman who has type A blood. They are both heterozygous, meaning that the man's genotype is "iBi" while the woman's genotype is "iAi". Both parents will produce gametes as follows:
iBi = iB and i
iAi = iA and I
Using these gametes in a punnet square (see attached image), the following possible blood types are produced in the offsprings:
- type AB (iAiB)
- type A (iAi)
- type B (iBi)
- type O (ii)
