THE CELL CYCLE - bio quiz

Which of the following is the correct sequence of the four phases of mitosis?

Prophase, metaphase, anaphase, telophase

Which statement best describes the movement of water molecules in osmosis?

from a dilute to a more concentrated solution across a membrane

Which organelle is depicted in the transmission electron microscopy picture on right?

golgi apparatus

Outline the role of cyclins in living cells.

regulatory proteins involved in controlling the cell cycle and watching over the progress of the cell cycle

Which of the following are properties of phospholipids?

they have a hydrophilic phosphate head, they form a bilayer in water, they are amphipathic

Phases of the cell cycle

1. Interphase (G1, S, G2) 2. Mitosis (Prophase, Metaphase, Anaphase, Telophase) 3. Cytokinesis (cell division)

Which are the functions of membrane proteins?

Cell to cell communication and active transport (protein pumps)

State how we call the process of reproduction of prokaryotes.

Binary fission

The medium in which a donor organ for transplant is bathed in an isotonic medium, a solution of the same concentration as the cell cytoplasm. Why?

The organ must not lose or gain water

Which of the following organelles are surrounded by a single membrane?

II and IV (rough endoplasmic reticulum, lysosome)

Eukaryotic cells contain organelles which each have specific functions. Complete the table below, to identify the missing organelle names and the missing functions.

A: function of the golgi apparatus = processes proteins received from rough ER & send them in vesicles to cell membrane B: lysosome C: mitochondria D: function of mitochondria = produces energy in form of ATP through cellular "powerhouse" respiration

Which of the following are properties of cholesterol found in plasma membranes?

Acts as a channel for ion movement, reduces fluidity of the membrane

Outline two similarities between the structure of prokaryotic cells and eukaryotic cells.

Both have the plasma membrane Both contain cytoplasm

How did Pasteur's experiment with sterile broth in open flasks demonstrate the principle that cells only come from preexisting cells?

By demonstrating that sterile broth would not ferment in contact with air alone.

Define the term "cell differentiation" .

Cell differentiation is a process during which a cell changes from one cell type to another. This usually occurs during the development of a multicellular organism, when the zygote changes into numerous different cell types.

Describe one type of cell which is atypical to the concept of cell theory.

Giant algae = it is large, but it is not composed of a collection of smaller cells, it is all one large and big cell

Explain the evidence which supports the endosymbiotic theory of the evolution of the eukaryotic cell.

The evidence suggests that the chloroplast organelles were once free living bacteria. These organelles (mitochondria, chloroplast) were probably swallowed up, which would explain the double membrane. Another piece of evidence is related with the fact that some organelles are capable of undergoing binary fission. Lastly, these organelles share a part of DNA (but very small), and both contain ribosomes.

The Davson-Danielli model of the membrane structure proposed a layer of protein on the outside edges of membranes. Biological evidence caused them to refine their model and later the Singer-Nicholson model became accepted as a better model of membrane structure. Describe one piece of evidence that falsified the Davson-Danielli model.

The problematic part of their model was the placement of proteins in the phospholipid bilayer. They offered the possibility that the proteins are on top of the lipid bilayer, whereas in reality, as we later found out, the proteins are embedded within the bilayer.

Which characteristic of stem cells makes them useful for treating Stargadt's disease?

They can differentiate into retinal cells

Outline how the mitotic index can be used in the diagnosis of cancer?

We can use it and compare it with normal growth of tissues and evaluate it. It can also be used with prognostic intention. Meaning, it could predict and calculate the response to chemotherapy and the overall chance of survival.

Emergent properties are found in some biological systems. Which of the following properties is necessary for emergent properties to occur?

cells or tissues interact to function as a unit

Which of the following events happens during mitosis in a plant cell?

condensation of chromosomes

List two sources of stem cells that can be used in therapeutic treatment.

embryonic stem cells, umbilical cord stem cells

What is the difference between prokaryotic cells and eukaryotic?

mitochondria are found only in eukaryotic cells

Which of the following can cause the formation of a primary tumour, or cancer?

oncogenes, mutagens, metastasis