Biology Exam #2

A symporter is a carrier protein that will

transport two different molecular species in the same direction at the same time

As the radius of a spherical cell __#1____, its volume increases ___#2___ its surface area, and the ability of the cell to successfully support its metabolism __#3____.

#1 = increases, #2 = more quickly than, #3 = decreases

If you repeated Dr. Gorter's experiment comparing the surface area of red blood cells (RBCs) with the surface area of the phospholipids that compose the plasma membrane of RBCs, which of the following results would best represent Dr. Gorter's results?

1:2 ratio

What best describes the nature of the nuclear membrane?

A double phospholipid bilayer

Which of the following is true of lysosomes?

A. They are released from the cis face of the Golgi. B. Lysosomes may be used to break down "worn out" organelles. C. Lysosomes contain enzymes that hydrolyze polymers. D. All of the above are true of lysosomes. ***E. Only B and C above are true of lysosomes.***

Prokaryotic cells do not have

A. organelles. B. an endomembrane network. C. a membrane bound nucleus. D. Prokaryotic cells do not have A, B, or C. ***E. Prokaryotic cells do not have B or C.***

To be considered alive an organism MUST be able to

A. photosynthesize. B. reproduce. C. grow and metabolize. D. A and C. ***E. B and C.***

Which of the following are found in all prokaryotic and eukaryotic cells?

A. plasma (cell) membrane B. ribosomes C. cell wall D. All of the above ***E.Only A and B are found in all prokaryotes and eukaryotes***

Which of the following have no physical contact with the plasma membrane of cells?

A. the extracellular matrix B. the cytoskeleton C. integral proteins ***D. All of the above make physical contact with the plasma membrane of cells.***

In response to being heated, how will the cells likely respond?

By generating membrane phospholipids with fatty acid chains that have fewer C=C double bonds (unsaturations).

In response to being heated, how will the cells likely respond?

By generating membrane phospholipids with longer fatty acid chains

What do facilitated diffusion and active transport have in common?

Carrier proteins are used in both facilitated diffusion and active transport

In the figure above, what is likely true of the proteins labeled A (fibronectin) and C (integrin)?

Fibronectin is a peripheral membrane protein and integrin is an integral (transmembrane) protein.

Which of the following is true of cell membrane fluidity?

Fluidity can be regulated by varying the length and degree of saturation in the fatty acid chains of membrane phospholipids.

Histones are proteins that bind to chromosomal DNA in the nucleus. Based on that knowledge, which of the following is true?

Histone proteins will be synthesized by ribosomes in the cytoplasm

Animal cells are growing in an incubator at 37°C. The cells are then placed into an incubator at 47°C. Which of the following is most likely to happen

Initially, the plasma membrane of the cells become more fluid

Are plant cell walls chemically similar to prokaryotic cell walls? How are they the same or different?

No, Plant cell walls are made of cellulose and bacterial cell walls are made of peptidoglycans

All cells fall into one of two broad categories. What are they

Prokaryotes and Eukaryotes

Where precisely are ribosomes assembled in eukaryotic cells?

The nucleolus

What is most likely true of phospholipids that will become part of a cell's plasma membrane?

They are synthesized in the smooth ER and sent to the plasma membrane by exocytosis.

Evert Gorter used red blood cells (RBCs) in his experiment for several good reasons. Which reason below is the most important reason that he used RBCs?

Within an individual organism all RBCs are the same size.

Lipid bilayer membranes (LBMs) are more permeable to some types of molecules than others. Which option below gives the correct order (from left to right) starting with of the types of molecules that LBMs are the least permeable to and ending with the types of molecules that LBMs are the most permeable to?

ions, small polar molecules, non-polar molecules

Which of the following is not a function of the extracellular matrix (ECM)?

reinforcing structures within cells that allow mobile cells to move

Evert Gorter's experiment with red blood cells demonstrated

that plasma membranes are phospholipid bilayers

The photo-bleaching experiments we discussed in class demonstrated

the fluid mosaic model of plasma membranes.

Within the chloroplast there is a thick liquid substance called

the stroma