Question

1. which of the following statements is false: a) phagocytosis is a protective mechanism use to get substances into the cell. the cell engulfs large particles such as bacteria or dead body cells. b) pinocytosis is when the cell ingests droplets of extracellular fluid containing dissolved proteins or fats. c) receptor - mediated endocytosis is a highly selective process of taking in substances such as enzymes, some hormones, cholesterol, and iron. receptor proteins on the membrane surface bind only certain substances and only those target molecules will enter the cell d) exocytosis is a passive process. all substances move out of the cell by means of exocytosis. 12. during mitosis, the stage of prophase includes all the following events except: a) the nuclear envelope/membrane and nucleolus dissolve b) the centrioles move to opposite ends of the cell c) the cellular dna is replicated to make 2 identical copies of the genetic material d) mitotic spindle formation begins and attaches to the centromeres of chromosomes 13. the 2nd stage of mitosis, metaphase, is defined by the following process: a) the nuclear envelope/membrane and nucleolus dissolve b) mitotic spindle pulls the chromosomes to opposite poles of the cell c) centrioles cluster and align in the middle of the cell, midway between the chromosomes that are at opposite end of the cell

Explanation:

1. Exocytosis is an active process, not passive, and not all substances move out of the cell by exocytosis. So statement d is false.
2. DNA replication occurs in the S - phase before mitosis, not in prophase. So statement c is not an event of prophase.
3. In metaphase, the mitotic spindle aligns the chromosomes in the middle of the cell (equatorial plane). None of the given options are correct definitions of metaphase. The correct process is that chromosomes line up along the metaphase plate.

Answer:

1. d
2. c
3. None of the above