The number of connections among species
A sex cell that hasn't been fertilized and has left the ovary would come out during the menstrual cycle under normal circumstances.
Answer:
1:1:1:1 walnut comb
Explanation:
If a cross is made between a female who is RRpp (rose comb) and a male who is rrPP (pea comb) then:
P: RRpp x rrPP
F1: RrPp RrPp RrPp RrPp
This means that all of the offspring in F1 generation will have heterozygous genotype (at both loci). Since it contains both dominant alleles, the phenotype is walnut comb.
The laboratories have initiated Phase 1 clinical trials for the use of human pluripotent embryonic stem cells to treat paralyzed patients following spinal cord injury. The first step is to estimate the risks and tolerance of cell transplantation in a man. The fate of stem cells (multipotent or pluripotent) in the body is still poorly understood, and it is not excluded that uncontrolled cell multiplications occur, leading to the appearance of teratomas (tumor developed from pluripotent cells).
Advantages are:
* The safety of the cells also seems to be proven (in short term)
* Rats transplanted seven days after the injury had benefited from reactivation of myelinization of neurons by oligodendrocytes, attenuation of motor neuron loss and improvement of limb motor function.
The disadvantages are:
* Constraints of the ethical and religious order, it is necessary the consent and the approval of the donor and the recipient for the transplant to take place.
* The development of the technique is still new, there is a chance that side effects of the transplant appear years after the operation.
