Cell Cycle

APB - Unit 4 - Cell Communication & Cell Cycle 3 #GoBioRams

Multiple Select

Which of the following items are found in a chromosome after the S phase of the Cell Cycle? Check all that apply.

• Chromatid

• Centromere

• DNA

• Histones

Multiple Choice

Which phase of the Cell Cycle lasts the longest?

• Interphase G₁

• Interphase S

• Interphase G₂

• Mitosis

• Cytokinesis

Multiple Choice

When is the cell cytoplasm actually splitting in two?

• Interphase G₁

• Interphase S

• Interphase G₂

• Mitosis

• Cytokinesis

Multiple Choice

At which phase does the nuclear envelope and the nucleolus disappear? The two now more condensed sister chromatids are joined together at the centromere?

• Interphase G₂

• Prophase

• Prometaphase

• Metaphase

• Anaphase

Multiple Choice

At which phase are the sister chromatids separated and are moved to opposite sides of the cell?

• Interphase G₂

• Prophase

• Prometaphase

• Metaphase

• Anaphase

Multiple Choice

At which phase are the kinetochores attached to the cetromeres?

• Interphase G₂

• Prophase

• Prometaphase

• Metaphase

• Anaphase

Multiple Choice

At which phase are the centrosomes with their centriole pairs visible at only one spot on the cell?

• Interphase G₂

• Prophase

• Prometaphase

• Metaphase

• Anaphase

Multiple Choice

At which phase is the Asters first visible since the microtubules are now beginning to extend within the mitotic spindle?

• Interphase G₂

• Prophase

• Prometaphase

• Metaphase

• Anaphase

Multiple Choice

Which organisms undergo Binary Fission?

• Prokaryotes

• Eukaryotes

Multiple Choice

Which organisms will display a cleavage furrow?

• Prokaryotes

• Eukaryotic animal cells

• Eukaryotic plant cells

Multiple Choice

Which organisms will form a cell plate during cell division?

• Eukaryotic animal cell

• Eukaryotic plant cell

How do cells "control" when to undergo cell division?

Cell Cycle Check Points

The textbook is a bit dated, keep that in mind.

• Fig. 12.15, 12.16, and 12.17 on pages 243 to 245.

• Growth factors (GFs) are used to signal the need to grow new cells.

• Healthy cells have density-dependent inhibition = too crowded -> stop dividing.

• Healthy cells also have anchorage dependance = they need to stick to the appropriate extracellular matrix for support.

Go to page 244

• Cyclins = purple = concentration gradient that determines when the cell will proceed to the next phase

• Cyclin dependent kinases (CDKs) = orange = always present in the cell = will be activated only if cyclin attaches

• Maturation promoting factor (MPFs) = orange & purple = activated and will phosphorylate (add phosphates) to proteins

Interestingly as people began to study cancer cells

• Cancer cells ignore density-dependent inhibition.

• Cancer cells ignore anchorage dependence.

• Cancer cells also just look odd.

• Fig. 12.19 on page 246

HeLa Cells

How we learned more about cancer.

https://www.goodreads.com/en/book/show/6493208-the-immortal-life-of-henrietta-lacks

A possible new approach.

Using Prokaryotes.

A review

• We discussed Cell Cycle Regulation.

• We discussed how Cancer is tied to the Cell Cycle.

• We discussed how Cancerous cells are physically different from healthy cells.

• We also introduced various research techniques.

Next Up

Meiosis and Classical Genetics