Answer:
1. There is a small sample of the disease that's being tried to prevent so that the body can get used to fighting it.
2. In the vaccine there is a small sample of a disease that the vaccine is being used to prevent. The white blood cells fight harmful bacteria and so prevent diseases.
3. A vaccine works by training the immune system to fight viruses or bacteria.
4. The antigenic variability of the virus and other viruses and bacteria acts as infective agents.
<h3><u>Answer;</u></h3>
Whereas segregational petites exhibited Mendelian inheritance, both neutral and suppressive petites followed non-Mendelian patterns that were consistent with the involvement of an extranuclear agent
<h3><u>Explanation</u>;</h3>
- Mutations that yield defective mitochondria are expected to make cells grow much more slowly. These mutants were called petites to describe their small colonies compared to large wild type colonies.
- Petite mutants could not grow when cells had an energy source requiring only metabolic activity of mitochondria - needed sugar as well which is part of glycolytic pathway.
- Segregational petites, segregated in mendelian manner during meiosis. mutations cause defects in genes in cell nucleus encode proteins necessary for mitochondrial function.
- Vegetative petite mutants do not segregate in mendelian manner; two types: neutral and suppressive; carry mutations in mitochondrial genome itself; when two yeast cells are mated, daughter cells inherit mitochondria from both parents.
- Neutral petites lack most of their mitochondrial DNA; when mated with wildtype, the wildtype give their mitochondria so all cells display a normal phenotype.
DNA or deoxyribonucleic acid is macromolecule composed of nucleotides (nitrogen nucleobase, deoxyribose sugar and phosphate group) which carries genetic information (instructions). Instructions within DNA are for development, growth, reproduction and many other functional roles of an organism.
All of the cells within an organism contain the same genome (full set of DNA-chromosomes). When cells begin the process of differentiation (cells become specified) their genome stays the same, but the gene expression is different (different genes are on or off).
