Motor neuron disease includes loss of motor neurons in the anterior horns of the spinal cord and motor nuclei of the lower brain stem.
Answer:
Cross-pollination.............
Answer:
F1 Females - all wild type
F1 Males - all wild type
F2 Females - - all wild type
F2 Males - 1/2 wild type, 1/2 vermilion
Explanation:
The wild-type allele (Xᵛ⁺) is dominant over vermilion (Xᵛ), which is a sex-linked trait.
Female flies have two X chromosomes, male flies have one X and one Y chromosome.
A homozygous wild-type female fly (Xᵛ⁺Xᵛ⁺) is mated with a vermilion male fly (XᵛY).
The female parent can only produce Xᵛ⁺ gametes.
The male parent can produce either Xᵛ or Y gametes.
When gametes from both parents fuse, the F1 offspring will have the genotypes Xᵛ⁺Xᵛ (females with wild type eyes) and Xᵛ⁺Y (males with wild type eyes).
The F1 females can produce Xᵛ⁺ and Xᵛ gametes. The F1 males can produce Xᵛ⁺ and Y gametes.
When the F1 individuals interbreed, the gametes combine to give rise to the F2 offspring. The possible combination of gametes that will give the different genotypes and phenotypes in the F2 are:
- Xᵛ⁺Xᵛ⁺ females with wild type eyes
- Xᵛ⁺ Y males with wild type eyes
- Xᵛ Xᵛ⁺ females with wild type eyes
- Xᵛ Y males with vermilion eyes
The failure of homologous chromosomes to separate properly is during meiosis where mutation appear
Static Electricity - the word static means 'at rest' - this kind of electricity exists when objects separated by an insulator has a build up of opposite charges. Because the attraction between these charges is so strong, they can flow even through great insulators. Ex: lightning, friction
Current Electricity - it makes electronic devices possible. There is a constant flow of charges in this type of electricity. In contrast to static electricity, current electricity is changing, dynamic and always on the move. Ex: starting a car, watching TV, using an electric stove.
