Genetics, blood type gene has two alleles, each allele has genotype A, B or O. The A and B are dominant, and O is recessive. So allele A combined with allele O is type A. Similarly, BO is type B, AA is type A, BB is type B, OO is type O, and AB is typeAB.
If both parents have type A blood, then the alleles could be AA or AO, thus the allele A frequency is 75%, allele O frequency is 25% for both parents.
So the chance of alleles OO is 25% × 25% = 6.25%,
alleles AA is 75% × 75% = 56.25%,
alleles AO is 75% × 25% = 18.75%,
alleles OA is 25% × 75% = 18.75%.
Since AA, AO and OA are blood type A, and OO is blood type O, thus their child has 6.25% chance to be blood type O and 93.75% chance to be blood type A.
The +/- is called the rhesus factor, with + being dominant, and - being recessive.
So if both parents are -, the kids are always -, otherwise the kids might be + or -.
Child Blood Type Estimate Table:
Father's Blood TypeABABOMother's
Blood
TypeAA/OA/B/AB/OA/B/ABA/OBA/B/AB/OB/OA/B/ABB/OABA/B/ABA/B/ABA/B/
Answer: A neuron has three main parts: dendrites, an axon, and a cell body or soma , which can be represented as the branches, roots and trunk of a tree, respectively. A dendrite (tree branch) is where a neuron receives input from other cells. Dendrites branch as they move towards their tips, just like tree branches do, and they even have leaf-like structures on them called spines.
The axon (tree roots) is the output structure of the neuron; when a neuron wants to talk to another neuron, it sends an electrical message called an action potential throughout the entire axon.
The features of neurons help them to carry out their function efficiently:
they have a long fibre (axon) so they can carry messages up and down the body over long distances
in a stimulated neuron, an electrical nerve impulse passes along the axon
the axon is insulated by a fatty (myelin) sheath - the fatty sheath increases the speed of the nerve impulses along the neuron
at each end of the neuron are tiny branches (dendrons), which branch even further into dendrites - the dendrites receive incoming nerve impulses from other neurons
Explanation:
Hope this is helpful!!
Pollination occurs when pollen grains from the anther land on a stigma. After pollen grains land on the stigma, a pollen tube grows from the pollen grain, through the style, and into the ovary. Sperm cells inside the pollen grain travel down the pollen tube and into the ovary which contains the ovules.
Mitosis is a type of cell division which results in two daughter cells which have the same number and kind of cells as the parent nucleus. Mitosis is used to replace worn out cells and for growth. In plants, a new cell was is built between the daughter cells, while in animals the cell membranes constrict and pinch the parent cell into daughter cells.