Answer and Explanation:
In rest, attraction strengths between myosin and actin filaments are inhibited by the tropomyosin. When the muscle fiber membrane depolarizes, the action potential caused by this depolarization enters the t-tubules depolarizing the inner portion of the muscle fiber. This activates calcium channels in the T tubules membrane and releases calcium into the sarcolemma. At this point, tropomyosin is obstructing binding sites for myosin on the thin filament. When calcium binds to the troponin C, the troponin T alters the tropomyosin by moving it and then unblocks the binding sites. Myosin heads bind to the uncovered actin-binding sites forming cross-bridges, and while doing it ATP is transformed into ADP and inorganic phosphate which is released. Myofilaments slide impulsed by chemical energy collected in myosin heads, producing a power stroke. The power stroke initiates when the myosin cross-bridge binds to actin. As they slide, ADP molecules are released. A new ATP links to myosin heads and breaks the bindings to the actin filament. Then ATP splits into ADP and phosphate, and the energy produced is accumulated in the myosin heads, which starts a new binding cycle to actin. Z-bands are then pulled toward each other, thus shortening the sarcomere and the I-band, and producing muscle fiber contraction.
<span>I is dominant, i is recessive. The A's and B's are just show which allele I is. When there is just one dominant allele, it masks the recessive in blood typing. Remember IA and IB are codominant.
O is always ii
A is IAi (heterozygous) or IAIA (homozygous)
B is IBi (heterozygous) or IBIB (homozygous)
AB is always IAIB
Remember: You get one allele from each parent!
1. Father must be ii, mother must be ii, so all children must be ii.
2. Father is IAIA (the homozygous one), the mother is IBIB, so the only possibility for the children is IAIB, because you get one allele from the father and one from the mother.
3. Father is IAi, mother is IBi, so the children can be any of the blood types, because they can have all the combinations of genotypes.
4. Father is ii, mother is IAIB. Children can only be IAi or IBi.
5. Father is IAIB, mother is IAIB. Children can be IAIA, IBIB, or IAIB.
Example of Punnett square:
3. Father is type A, heterozygous, mother is type B, heterozygous
Father must be IAi (heterozygous)
Mother must be IBi (heterozygous)
_______IA ____ i
IB____ IBIA____IBi
i _____ IAi______ii
Sorry, that was difficult on here, hope it's understandable.
The father's alleles run across the top, the mother's are on the side, you follow to where they meet to find the possibilities for the children. IBIA (AB blood type), IBi (B), IAi (A), and ii (O) are the possibilities in this case.
Hope that helps!</span>
The bonds are phophodiester bonds between phosphate group of each deoxyriboneucleotide.
When writing a hypothesis, you need to be able to say IF this, THEN this will happen.
Answer:
First, the zygote becomes a solid ball of cells. Then it becomes a hollow ball of cells called a blastocyst. Inside the uterus, the blastocyst implants in the wall of the uterus, where it develops into an embryo attached to a placenta and surrounded by fluid-filled membranes.
