Pg 243

1) Cells divide because the larger the cell becomes, the more demands the cell places on its dNA. The more trouble the cell has moving nutrients and wastes across the cell membrane.

2)The cells DNA is like books in a library because it supplies all the information for the cell.

3)The solution to the problem caused by cell growth is the daughter cell gets 1 complete set of genetic information.

4)As a cell increases in size volume increases more rapidly.

5)The ratio of surface area to volume in a cubic cell with a length of 4cm is 1.5:1



Pg 249

1) The main events of the cell cycle is prep for mitosis, mitosis, cell growth and DNA replication.

2) Prophase- chromosomes become visible, centrioles take up positions on opposite sides of the nucleus.

Metaphase- Chromosomes line up across the center of the cell.

Anaphase- Chromosomes move until they form groups near the poles of the spindle.

Telophase- Nucleolus becomes visible in each daughter nucleus, nuclear envelope reforms around each cluster of chromosomes.

3) Interphase is the period of cell growth between divisions of the cell.

4) Chromosomes are made of chromatids.

5) Prokaryotic cells divide by the simple matter of seperating the contents of the cell into two parts.

6) Cytokinesis in plant cells is similar to cytokinesis in animal cells because the cell membrane is drawn inward until the cytoplasm is pinched into 2 nearly equal parts.



Pg 252

1) The chemicals that regulate the timing if the cel cycle are cyclins.

2) The thing that happens when cells do not respond to the signals that normally regulate thier growth is that they will stop dividing.

3) The way cells respond to contact with other cells is they stop growing.

4) Cancer can be considered a disease of the cell cycle because it affects the cells during cell division.

5) If cyclin were injected into a cell that was in mitosis then it would speed up or slow down the process because cyclin regulates timing.

Pg 257
1) A
2) C
3) B
4) C
5) C
6)A
7)B
8)B
9)A
10)A

Cell Division- A process by which a parent cell divides into 2 cells creating daughter cells.

Chromatid- One of the two side by side replicas produced by chromosome replication in mitosis. Subunit of a chromosome after replication and prior to an anaphase.

Centromere- Centromeres are highly complex chromosomal substructures involved in essential aspects of chromosome transmission during cell division. The centromere/kinetochor complex is responsible for directing chromosome movements in mitosis and for faithful progression of mitotic events at the transition between metaphase and anaphase.

Interphase- During interphase, cellular organelles double in number, the DNA replicates, and protein synthesis occurs. The chromosomes are not visible and the DNA appears as uncoiled chromatin.

Cell Cycle- An ordered set of events, culminating in cell growth and division into two daughter cells. Non-dividing cells not considered to be in the cell cycle.

Mitosis- is a process of cell division which results in the production of two daughter cells from a single parent cell. The daughter cells are identical to one another and to the original parent cell.

Prophase- During prophase the chromosomes are identical chromatids connected at the center by a centromere, forming an X-shaped object.

Centriole- one of a pair of cellular organelles that occur especially in animals, are adjacent to the nucleus, function in the formation of the spindle apparatus during cell division, and consist of a cylinder with nine microtubules arranged peripherally in a circle.

Spindle- Pull the chromatids toward the spindle poles, and lengthen and elongate the cell.

Metaphase- -In Metaphase the kinetochores that are responsible for moving the chromosomes jump begin to orientate the chromosomes.

Anaphase- is a stage in mitosis and meiosis where chromosomes begin moving to opposite ends (poles) of the cell.

Telophase- the final stage of meiosis or mitosis, in which the separated chromosomes reach the opposite poles of the dividing cell and the nuclei of the daughter cells form around the two sets of chromosomes.

Cytokinesis- is the process whereby the cytoplasm of a single cell is divided to spawn two daughter cells.

Cancer- Develops when cells in a part of the body begin to grow out of control.

Cyclin- are eukaryotic proteins that play an active role in controlling nuclear cell division cycles and regulate cyclin dependent kinases.

Marcello Malpighi

Hi, mi nombre es Marcello Malpighi. Aka "Notorious P.I.G." I enjoy hanging with big "Lui G" Biology is the main part of my life. If im not with Lui G im studying biology or finding ways to make biology more fun and interesante.

Gracias,
Notorious P.I.G.