Answer: Even though the allele is recessive it is passed down from parent to child and if both parents have the recessive allele it is possible the child will have sickle cell as it is inherited.
Explanation:
Hello!
Natural selection is the way that animals evolve.
The theory of natural selection is that the animals that do not have a specific trait to survive in their environment will die. The animals that do have the trait will survive. The animals that survive will then pass the trait down to their offspring, who will also likely survive because they have the trait. This is how species evolve and continue to survive in their environment.
The species evolve because only the fittest survive (this is known as "survival of the fittest"). The animals that do not have the needed traits will die and they cannot have offspring.
I hope this helps answer your question! Have a great day!
Answer:
RrYy (F1 generation)
Explanation:
This is a typical dihybrid cross involving two genes in the pea plant; one coding for seed colour and the other for seed shape.
According to Mendel's law of dominance, an allele is capable of masking another allele in a gene, the allele that masks or is expressed is called the DOMINANT allele while the allele being masked is called RECESSIVE allele.
Homozygosity of a gene refers to it having the same type of alleles while heterozygosity refers to having different alleles.
In this example, allele for Round (R) and Yellow (Y) pea is dominant over the allele for Wrinkled (r) and green pea respectively.
Homozygous round green pea (RRyy) crossed with Homozygous wrinkled yellow (rrYY) will give rise to a heterozygous round yellow (RrYy) F1 offsprings.
Concordance rates between monozygotic twins vary in different studies, approximately 50%; whereas dizygotic twins was 17%. Some twin studies (Koskenvuo et al; Hoeffer et al) have found rates as low as 11.0%–13.8% among monozygotic twins, and 1.8%–4.1% among dizygotic twins.
Answer:
1. Acetylcholine binds to receptors on the motor end plate
2. Ligand-gated channels open leading to depolarization
3. End plate potential triggers an action potential
4. Transverse tubules convey action potentials into the interior of the muscle fiber
5. Calcium is released from the sarcoplasmic reticulum
6. Calcium ions bind to troponin, which then moves tropomyosin
Explanation:
Acetylcholine (ACh) is a signaling molecule (neurotransmitter) that binds to receptors on muscle cells. This binding triggers the opening of ligand-gated sodium channels, thereby ions enter into muscle cells, which causes the depolarization of the sarcolemma and thus promotes the release of Ca2+ ions from the sarcoplasmic reticulum. The myoneural junction, also known as the motor endplate, is the site of synaptic contact between a motor axon and a skeletal muscle fiber. The endplate potential is the voltage that produces the depolarization of muscle fibers when ACh molecules bind to their receptors in the cell membrane. This depolarization spreads in the sarcolemma through transverse tubules (T tubules) and thus generates an action potential. Finally, this action potential induces the release of Ca2+ in the sarcoplasmic reticulum, which activates troponin protein and induces muscle contraction.
