<span>Vesicles are used to transport items in many different circumstances, so I'm not quite sure how to answer your question. Vesicles are used when transporting to and from the golgi apparatus, also when transporting molecules to lysosomes. They are even used when undergoing exocytosis. Basically, they are used to carry items/molecules/wastes around within cells
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There are exactly 24 chromosomes in a girl cell and 24 in a boy cell.
Answer:
The correct insulin pathway is described as under:
2. Binding of insulin to the alpha subunit of the insulin receptor
8. Activation of insulin receptor tyrosine kinase
3. Phosphorylation of IRS proteins
6. Phosphorylation of phosphinositide 3-kinase (PI-3K)
4. Conversion of PIP2 to PIP3
7. Activation of PIP3-dependent protein kinase B (PDK1)
5. Glut4 receptors transported to the cell membrane
Explanation:
The insulin signaling pathway is described as under:
RTK (receptor tyrosine kinases) which is a receptor for insulin is an extracellular receptor but in contrast to other cell surface receptors it is catalytic in nature. In the absence of insulin (ligand), it is monomeric but as soon as it gets activated (activation occurs upon ligand binding), it undergo dimerization. It leads to auto-phosphorylation in it's tyrosine residue which subsequently leads to phosphorylation of tyrosine residue of other receptors. Such hyper-phosphorylated receptor have high affinity with enzyme/molecule like IRS protein which have SH2 domain . IRS down stream activates phosphinositide 3-kinase (PI-3K). This enzyme converts component of animal cell membrane PIP2 into PIP3. PIP3 also remains membrane bound but it has the potential to phosphorylate another enzyme named as PIP3-dependent protein kinase B (PDK1). Further, PDK1 leads to the activation of Akt or PK-B. Akt is a serine-threonine kinase which ultimately leads to the recruitment of Glut4 receptors on cell membrane for uptake of more and more glucose into the cell.
Note: Apart from this Akt also phosphorylates another protein named as FOXO which ultimately causes cell growth, Akt can also phosphorylate BAD protein so as to restrict cell apoptosis or we can say it leads to cell survival, Akt also leads to translation in a cell with the help of mTOR raptor etc.
The answer is D, for when one tropic level is eaten by the tropic level above it, the tropic level is supporting the higher one. I. E. Rabbits are supported by the grass because rabbits eat the grass. Also, the grass population would be larger than rabbits, the rabbits larger than snakes, so on and so forth, so B is ruled out. B states that each population is larger than the one BEFORE it, but there is no way there would be more rabbits than grass. Also, there are both herbivores and carnivores in the food chain, so A and C are out. The best answer is D.
The answers that best fit the blanks are MATERNAL BLOOD ANALYSIS and ULTRASOUND, respectively. In prenatal diagnosis, there are certain methods that should not be done routinely for the reason that these may injure the fetus, except for routine ultrasound, which checks the status of the fetus, and maternal blood analysis, which assesses the current status of the mother.
