Biology Chapter 10

Why cells do not grow to a very large size?

DNA overload occurs in large cells, large cells have a small surface area: volume ratio, so they use up more materials and make more waste and need to exchange a lot more materials across the cell membrane, but this exchange is too slow due to the relatively small surface area of the cell membrane.

What are the 4 cell phases in order?

Interphase, cell division, mitosis, cytokinesis

What are the parts of a chromosome

1 chromosome is made up of 2 identical halves called sister chromatids. The 2 sister chromatids are held together by a protein called the centromere.

\n What are the 4 phases of mitosis?

\n Prophase, Metaphase, Anaphase, and Telophase

Cytokinesis occurs...

following mitosis, usually occurring at the same time as Telophase, but it can start in late anaphase.

How do you tell a plant from an animal cell during cell division?

Cytokinesis method; Centrioles are found only in animal cells, not plant

Know what the M phase is

Cell division; Mitosis and Cytokinesis

What are 3 things that regulate the cell cycle?

External and Internal Regulates

What is a tumor?

a collection of cells; it may be cancerous or not

When are chromosomes visible under the microscope during the cell cycle and why?

During cell division bc the chromosomes are thickened (tightly coiled) to become not tangled.

the chromosome number _____________ throughout the cell cycle that involves mitosis.

stays the same

How do cells solve the problem of being too large in size?

\n they divide into 2 smaller daughter

Cell Cycle Def.

series of events that cells go through as they grow and divide

What happens in the Interphase (3)

G1; Cell grows and new organelles are replicated S; DNA are replicated G2; Cell grows and copies organelles and produces proteins

What happens in Cell Division?

1 parent cell produces 2 daughter cells, each with a copy of the parent cell DNA

What happens in mitosis

nuclear division

what happens in cytokinesis

cytoplasm division

which parts are cell division?

mitosis and cytokinesis

Chromatic

\n threadlike DNA during interphase

Chromosomes

double-stranded and thickened (tightly coiled) DNA during prophase and metaphase of mitosis

Daughter chromosomes

single-stranded and thickened DNA during anaphase and telophase of mitosis

What happens in prophase

chromosomes get thick and visible as double-stranded, spindle fibers form and attach to the kinetochore, nucleolus disappears, nuclear membrane disappears in late prophase

What happens in metaphase

chromosomes line up at the equator

What happens in anaphase

Chromosomes split in half at the kinetochore and move as daughter chromosomes to opposite poles of the cell

What happens in telophase?

\n 2 daughter nuclei form around the 2 sets of daughter chromosomes, nucleolus reappears

Animal cytokinesis

Cell membrane pinches from the outside inward by encircling the parent cell cytoplasm with microtubules.

Plant cytokinesis

Cell plate forms first in the cell center and moves outward in each direction until the cell is now 2 daughter cells.

External Regulators

Cells contacting other cells and Growth factors.

Internal Regulators

Cyclins and DNA replication in S phase of interphase.

What is cancer?

uncontrolled cell division that occurs too fast before the cells have had a chance to replicate their DNA

When are chromosomes NOT visible under the microscope during the cell cycle and why?

During interphase bc the DNA and proteins(chromatin) is long, thin, and threadlike