Answer:
1/4.
Explanation:
Via a punett square, the only possible combinations are AA, AB, AO and BO. Since BO is the only way the child has type B, the chances are 1 in 4.
Answer:
Explanation:
Meiosis is a form of cell division that occurs in the sex cells of organisms. It ensures the reduction of a diploid cell to an haploid cell to allow for the formation of a diploid zygote after fertilization (contribution of both parents haploid sex cells to give a diploid zygote). Thus, this process is very essential and important.
The reduction is accomplished by 2 divisions after the duplication of chromosomes
- first division: separation of homologous pairs of chromosomes (this reduces the total in half)
- second division: separation of sister chromatids of a chromosome.
The rearrangement in meiosis occurs by crossing over/genetic recombination.
This is the exchange of genetic material between homologous pairs of chromosome bringing about a rearrangement and genetic variation
An example of a chromosomal abnormality that arises as a result of defects in this process is the Down Syndrome which is caused by a nondisjunction of the chromosomes 21 pair in a sex cell.
This condition produces offsprings that have some characteristic facial features, short stature etc
If blood typing is not available in an emergency situation, O-Negative blood is universally accepted by all blood types because it is absent of any antibodies. Therefore, if O-Neg blood is on hand in emergency situations, it can be given to anyone.
Answer:
Menisci are the semi-lunar fibrous cartilage of the knee which could be either medial meniscus or radial meniscus. The meniscus in humans is present in the joints of the knee, sternoclavicular joints, wrist and temporomandibular joints.
These menisci play important roles in these joints as they reduce the friction caused by the bones during movement. They also disperse the weight of the body of the humans as they spread the load of the weight of the body to different bones like the femur and tibia.
