Which of the following statements regarding microtubules is FALSE?   A Microtubules are polar.   B Microtubules are inherently unstable and rapidly disassemble with low GTP concentrations.   C Microtubule-binding proteins, such as Tau, always bind to microtubules to destabilize them.   D Microtubules are composed of 13 protofilaments that are arranged into a hollow cylinder.   E Microtubules are typically arranged in cells such that their plus (+) ends are directed towards the plasma membrane and their minus (-) ends are attached to the centrosomes.

I have a biology question: The ribosomes of eukaryotic cells are found: a. On rough endoplasmic reticulum and in the cytoplasm B. In the cytoplasm and nucleoli C. On the smooth and rough parts of endoplasmic reticulum d. On all biomembranes   All of the following are involved in the movement of a substance across a semi permeable membrane EXCEPT: a. The size of the phospholipids b. The polarity of the substance c. The molecular size of the structure d. The concentration of tghe substance on either side of the membrane

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QUESTION 7 Match the stage of mitotic cell division with its description. vchromosomes line up in the middle of the cell on spindle fibers cytoplasmic division results in two new cells A. interphase sister chromatids separate and daughter chromosomes begin moving to opposite poles B. anaphase C. telophase nuclear membrane disintegrates, DNA condenses, spindle highways begin to D. metaphase be formed E. prophase F. cytokinesis daughter chromosomes arrive at opposite ends of the cell, the cell |- vmembrane pinches in, nuclear membranes form Ev DNA replication and organelle doubling

Short Question:-2 Course Code: BIO121 Course Name: Principles of Biology I (a) Plasma membrane is said to be selectively permeable. Explain what is meant by that. (b) Describe the differences between a plant cell and animal cell. (c) List the three animal cell junctions and give their functions

QUESTION 48 With regard to the process of mitosis, which of the following pairs is NOT matched correctly? Oa. Interphase - the cell grows, chromosomes replicate, and proteins are produced to prepare the cell to divide b. Prophase - chromosomes condense, and the nuclear membrane dissociates/breaks down c. Metaphase - chromosomes move toward opposite poles (or sides) of the cell d. Anaphase - sister chromatids separate e. Telophase - two distinct nuclei are formed; this is the stage immediately before cytokinesis

Phosphorylation of nuclear lamins regulates their assembly and disassembly during mitosis. You add a drug to cells that are undergoing mitosis that inhibits the activity of an enzyme that dephosphorylates nuclear lamins. What do you predict will happen to these cells? Why?

QUESTION 7 Match the stage of mitotic cell division with its description. chromosomes line up in the middle of the cell on spindle fibers cytoplasmic division results in two new cells A. interphase sister chromatids separate and daughter chromosomes begin moving to gopposite poles B. anaphase C. telophase nuclear membrane disintegrates, DNA condenses, spindle highways begin to D. metaphase be formed E. prophase F. cytokinesis daughter chromosomes arrive at opposite ends of the cell, the cell membrane pinches in, nuclear membranes form DNA replication and organelle doubling

Cancer, the uncontrolled growth of cells, often results in a tumor, or mass of abnormal cells. Some cancerous tumors consist of many cells that are much smaller than normal. According to Figure 1, what part of the cell cycle is most likely being affected? Explain.

Question 7 Which of the folowng statements about an adult animal with a newly-acquired mutation in a somatic cell is true? O Some (but not all) of the animal's offspring wil carry the mutation. OAl d the animal's offspring will carry the mutation. O The animal but not ts offspring, might be affected by the mutation.