Exam 1 Top Hat Review Questions Flashcards
Pasteur’s experiments proved that ________.
preexisting cells present in the air can grow in sterilized nutrient broth
What compounds was Stanley Miller able to create in his 1953 chemical evolution experiments?
Hydrogen cyanide, formaldehyde, and amino acids
Which of these elements make up most of living matter?
Carbon, hydrogen, oxygen and nitrogen
An atom consists of ____
protons, neutrons and electrons
Bonds between two atoms that are equally electronegative are ________.
nonpolar covalent bonds
A covalent bond is likely to be polar when ________.
one of the atoms sharing electrons is more electronegative than the other atom
What types of bonds are broken when we boil water?
Hydrogen
When the atoms involved in a covalent bond have the same electronegativity, what type of bond results?
A nonpolar covalent bond
How many chemical bonds can carbon make?
4
If a solution that has a high pH ( basic), the H+ concentration is:
Low
Diet Pepsi solution has a high concentration of protons. What is the pH of Diet pepsi ( acidic, basic, neutral?)
Acidic
What component of amino acid structure varies among different amino acids?
The components of the R-group (side chains)
The primary structure of a protein:
is its amino acid sequence
Which level of protein structure do the α-helix and the β-pleated sheet represent?
Secondary
Fill in the blank. Alpha-helices have ⋯⋯⋯hydrogen bonds and beta pleated sheets have ⋯⋯⋯ hydrogen bonds.
intrastrand, interstrand
Lipids that contain a high number of double bonds in their fatty acid chains will ________.
likely be liquid at room temperature
Which component of phospholipids would be more comfortable interacting with water?
Polar heads
For a fish to survive in the bottom of an Iowa pond over the winter, the fish needs to maintain fluid cell membranes. It can do so, if it has ……..
More unsaturated fatty acids in its membrane phospholipids
When a membrane is freeze-fractured, the bilayer splits down the middle between the two layers of phospholipids. In an electron micrograph of a freeze-fractured membrane, the bumps seen on the fractured surface of the membrane are ________.
mostly integral and some peripheral proteins
For a protein to be an integral membrane protein, it would have to be ________.
amphipathic, with at least one hydrophobic region
Luciana’s microscope is equipped with a laser, and she is able to point the laser at a tiny spot on the cell membrane and bleach the GFPs in that spot. She continues to watch.
What will happen to the spot with time?
Grows smaller and eventually disappears
Eukaryotic cells are generally larger than prokaryotic cells
True
Which of the following macromolecules leaves the nucleus of a eukaryotic cell through pores in the nuclear membrane?
mRNA
Which type of organelle or structure is primarily involved in the synthesis of oils, phospholipids, and steroids?
Smooth endoplasmic reticulum
