1. a. 5.4 yoctometers per femtosecond
5.4 E-15nm /10E-15 seconds
2. 0.4 nanometer.
3. On the basis of etymology, there is no difference between ethics and morality. However, morality constitutes behaviors and beliefs about what is good and wrong while ethics is the moral philosophy or reasoning. Morality encompasses actions and beliefs while ethics is the philosophical reflection on morals and practices. Ethics is about thinking about moral actions and beliefs. Some of the ethical dilemmas such as euthanasia and assisted suicide are based on the moral of doing what is “right.”
4. Human experiments involve the use of human beings as experimental subjects. An experiment subject refers to an individual who is observed or experimented with by an investigator. All researches using human subjects must be reviewed and approved by the committee on the use of humans as experiment subjects (COUHES).
5. Stem cells are cells with both self-renewal and differentiation potentials i.e. undergoing symmetric or asymmetric divisions through which the stem population is maintained. They can differentiate into more than one cell lineage and can perpetuate tissues upon transplantation. There are two main types of stem cells (embryonic stem cells and adult stem cells). Based on their ability to differentiate, stem cells can be classified into totipotent, pluripotent, multipotent, oligopotent and unipotent stem cells. The major ethical issue surrounding the use of stem cells in research emanate from the derivation and pluripotent stem cell lines from oocytes and embryos. The ethical dilemma is based on either to respect human life or prevent/alleviate human suffering. There are questions on whether preimplantation embryos have moral standing equal to living humans.
6. Embryonic stem cells are derived from the inner cell mass of blastocyst, and primordial germ cells from a post-implantation embryo. One of the major differences between embryonic stem cells and somatic cells is their different abilities in the number and type of differentiated cells type they can become. Embryonic cells can become all cell types of the body while somatic cells are believed to be limited to differentiating into different cell types of their tissue of origin.
7. Induced pluripotent stem cells are genetically altered adult stem cells that are induced in a laboratory to take characteristics of embryonic stem cells.
8. Cell differentiation is the process through which young cells matures and specialize into distinct form and function. It’s the maturity process of cells where cells assume specific functions in the body.
9. DNA molecules pass through the nucleus membrane of a cell. Nucleocytoplasmic transport of macromolecules such as DNA, RNA, proteins, peptides, and so on, through the nuclear membrane is a fundamental process for the metabolism of cells. Transport of plasmid DNA through the nuclear pores has been implicated in numerous studies, particularly when the plasmids contain specific sequences recognized by the host cell transcription factor. DNA can pass through the nucleus membrane through the nuclear pores. Nuclear pores are embedded on the surface of nuclear envelope. The nuclear envelope separates the contents of the nucleus from the cytoplasm (Cooper Gm, 2000).
DNA can also enter into the nucleus through the association of DNA with the nuclear materials on the breakdown of the nuclear envelope during mitosis (Misra, 2011).
Cooper GM. The Cell: A Molecular Approach. 2nd edition. Sunderland (MA): Sinauer Associates; 2000. The Nuclear Envelope and Traffic between the Nucleus and Cytoplasm. Available from: http://www.ncbi.nlm.nih.gov/books/NBK9927/