exam one Flashcards
In the biosynthesis of macromolecules (polymers), monomers are bonded together by ______.
dehydration reactions
Which chemical bond holds DNA strands together?
hydrogen bonds
____ is the energy factory in eukaryotic cells.
Mitochondrion
Let’s suppose that a species of bacterium, Salmonella typhimurium, has acquired an antibiotic-resistant gene from a different species, such as Klebsiella pneumonia. This event is an example of ____.
horizontal gene transfer
Which of the following molecules is the most hydrophobic?
a. C3H7COOH
b. CH3OH
c. C2H6
d. C5H10O5
c. C2H6
______ is the post-office in eukaryotic cells.
golgi apparatus
Which of the following statements regarding nucleic acids is not true?
a. The two classes of nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).
b. DNA is responsible for the storage, replication, and transmission of genetic information.
c. RNA is responsible for decoding and expression of genetic information.
d. Hydrogen bonds hold inter-molecular or intra-molecular nucleotide strands together.
e. RNA is hydrophilic and DNA is amphipathic.
e. RNA is hydrophilic and DNA is amphipathic.
In terms of the movement of substances across the plasma membrane, it is said that the plasma membrane is ____.
selectively permeable
Which of the following statements regarding proteins is not true?
a. Protein shape (conformation) determines protein function.
b. Proteins are involved in almost every biological process.
c. Proteins are made of monosaccharides.
d. Protein conformation can be changed upon modifications, such as interaction with or binding of other molecules/ions.
e. Proteins have a hierarchy of structure at four progressive levels, primary, secondary, tertiary, and quaternary levels.
c. Proteins are made of monosaccharides.
Four major classes of organic molecules in living organisms are ___.
carbohydrates, lipids, proteins, and nucleic acids
Biological evolution, through microevolution and macroevolution, is based on ____.
variation within a given species and natural selection
Which atom is the building block of all living matter?
carbon
The common energy intermediates in cells include ____.
ATP and NADH
The web of life highlights ______ of all life on Earth.
a. unity
b. diversity
c. a shared evolutionary history
d. diverse living environments
e. all of these
e. all of these
Let’s suppose a solution of pure water at room temperature contains OH- ions at a concentration of 10-9 M. Calculate the pH of the solution.
a. 3
b. 5
c. 7
d. 9
e. 11
b. 5
By definition, a species is a group of related organisms that share _____.
distinctive traits
A(n) ___ is a portion of a protein with a particular structure and function.
domain
____ is the recycling center in eukaryotic cells.
lysosome
Which of the following can affect enzyme activity?
a. co-factors, usually metal ions
b. co-enzymes, usually organic molecules
c. temperature
d. pH
e. all of these
e. all of these
Most biological catalysts in chemical reactions are ___.
proteins
The principal pathway for uptake of organic molecules, such as sugars, amino acids, and nucleotides, is carried out by ______.
conformational change of membrane transporters (carriers)
_______ chemical reactions are used for recycling building blocks and for energy to drive endergonic reactions
catabolic
A hypothesis is commonly used in biological research to gain knowledge. A solid hypothesis must be ____.
testable and falsifiable
Facilitated diffusion of a substance across the plasma membrane ______.
requires a specific transport protein but does not require input of energy.
Enzymes speed up chemical reactions by ____.
lowering the activation energy necessary to initiate the reaction
Living organisms are composed mainly of which four atoms?
carbon, hydrogen, nitrogen, and oxygen
Which of the following is not true about the fluid-mosaic model of the plasma membrane?
a. Membrane is considered a mosaic of lipid, protein, and carbohydrate molecules.
b. Membrane resembles a fluid because lipids and proteins can move relative to each other within the membrane.
c. The two leaflets (halves of bilayer) are asymmetrical, with different amounts of each component.
d. Factors affecting fluidity include length of phospholipid tails, presence of double bonds in phospholipid tails, cholesterol, and temperature.
e. All membrane proteins possess one or more transmembrane domains.
e. All membrane proteins possess one or more transmembrane domains.
Homology occurs because _____.
different species evolved from a common ancestor
The properties of substrate-enzyme interactions include _____.
a. chemical specificity
b. affinity
c. saturation
d. competition
e. all of these
e. all of these
Populations of organisms change over the course of many generations. Many of these changes result in increased survival and reproduction. This phenomenon is _____.
evolution
According to the base paring rule in nucleic acids, ______.
a. A pairs with T (or U); C pairs with G
b. A pairs with G; C pairs with T (or U)
c. A pairs with A; T pairs with T, C pairs with C; G pairs with G
d. A pairs with C; G pairs with T (or U)
a. A pairs with T (or U); C pairs with G
Which of the following is an amphipathic molecule?
a. glucose
b. nucleotide
c. phospholipid
d. NaCl
e. H2O
c. phospholipid
How do you correctly write out a species’ scientific name?
italicized, first word capitalized, second word lower case
Which of the following is not a function of water in living organisms?
a. dissolves solutes
b. participates in chemical reactions
c. supplies energy
d. provides force or support
e. lubricates surface
c. supplies energy
Core concepts of Biology include _____.
a. evolution
b. structure and function
c. genetic information flow, exchange, and storage
d. pathways and transformations of energy and matter
e. systems
f. all of these
f. all of these
Genomes of closely related species tend to be more similar to each other than to distantly related species. This statement is ____
true
The blueprint (or genetic material) of all living organisms is ____
DNA
Which of the following is not regarded as evidence of evolutionary change in Biology?
a. fossil record
b. convergent evolution
c. selective breeding
d. homologies
e. biogeography
f. hypothesis
f. hypothesis
The cell theory states ______.
a. that all living things are composed of cells.
b. that cells are the smallest units of living organisms.
c. that new cells come from pre-existing cells by cell division.
d. all of these
d. all of these
Chemical reactions that release free energy are ___.
exergonic and spontaneous
Which of the following statements is correct?
a. Molecular shape determines molecular function.
b. Molecular function determines molecular shape.
c. Molecular shape is fixed and cannot be changed.
d. Molecular function is fixed and cannot be changed.
e. Molecular function is not affected by temperature.
a. Molecular shape determines molecular function.
What is the protein factory in cells?
ribosomes
Electrons in _____ bonds are shared to fill valence shells.
covalent
______ is the field of biology concerned with grouping and classification of species.
taxonomy
The framework of the biological membrane is ______.
the phospholipid bilayer
What features of a biological membrane are major contributors to its selective permeability?
phospholipid bilayers, channels, and transporters
When placed in a solution of water, a human skin cell bursts. Which of the following statements best explains why this happens?
a. The inside of the cell is hypertonic to the outside.
b. The inside of the cell is hypotonic to the outside.
c. The membrane contains transporters that allow the rapid movement of ions.
d. The membrane contains channels that allow the rapid movement of ions.
e. The membrane contains transporters and channels that allow the rapid movement of ions.
a. The inside of the cell is hypertonic to the outside.
A plant biologist spends 2 years observing three different species of desert plants in their native environment. Following this observation period, the research proposes that all three species drop their leaves to conserve water. This is an example of ___.
a hypothesis
In Biology, ______ structures are derived from a common ancestor.
homologous
Which of the following observations would not be considered evidence for the endosymbiosis theory?
a. Mitochondria and chloroplasts have genomes that resemble smaller versions of bacterial genomes.
b. Mitochondria, chloroplasts, and bacteria all divide by binary fission.
c. Mitochondria, chloroplasts, and bacteria all have ribosomes.
d. Mitochondria, chloroplasts, and bacteria all have similar sizes and shapes.
I think it is d. Mitochondria, chloroplasts, and bacteria all have similar sizes and shapes.
