The correct answer is: A. minus end; dynein
Microtubules are cytoskeletal fibers that have an important role in the intracellular transport (movement of vesicles within the cell) and in the mitotic spindle during mitosis. The plus end of the microtubules extend through the periphery of the cells while the minus ends are anchored within the centrosome.
Necessary proteins for the vesicle’s movement are motor proteins:
• kinesin which is positive end directed
• dynein which is negative end directed
So, beside vesicles these proteins are also involved in organelles’ transport in opposite directions through the cytoplasm.
Isotonic since in a hypertonic solution the cell would shrivel up and in a hypotonic solution it would lyse (burst).
There are 7 unifying themes in biology
1.Cell structure and function
2.Reproduction
3.Metabolism
4.Homeostasis
5.Heredity
6.Evolution
7.Interdependence
In general terms, “sex” refers to the biological differences between males and females, such as the genitalia and genetic differences. “Gender” is more difficult to define, but it can refer to the role of a male or female in society, known as a gender role, or an individual's concept of themselves, or gender identity.
