Bio 2
The atomic mass of neon is 20. This means it has ____
10 protons and 10 neutrons
A cell membrane has _____ layers of phospholipids.
2
A scientist has isolated an organic molecule from a new alien life form she is studying. Which statement is true about this organic molecule?
A carbon atom in this molecule will share electrons with one or more carbon atoms also contained within this molecule.
Which of these is an example of a nucleic acid?
DNA
Which statement does NOT apply to the term "energy"?
Energy is maintenance of a relatively stable environment
An alchemist is trying to create a human body by mixing together various elements. Which element would he NOT need to add to his reaction (i.e., which element is found in a human body)?
Nitrogen, oxygen, calcium, and carbon are all part of the human body.
Where are the protons, neutrons, and electrons located in an atom?
Protons and neutrons are located in the nucleus, and electrons are located in orbitals.
If phospholipid-like molecules in an alien species had charged tails and uncharged heads, how would these molecules be arranged in alien cell membranes, assuming that the cells and their surroundings are aqueous in the aliens?
The tails would be facing out, the heads would be facing in?
Whether or not viruses are alive is frequently debated. Name one characteristic of viruses that make them similar to other living organisms.
Viruses seem alive because they can reproduce themselves in host cells.
What characteristics make a particular molecule organic? Select the TWO answers that are correct.
a carbon backbone;a carbon-hydrogen bond
A substance that increases the hydrogen ion concentration of a solution is a(n) ____
acid
Microscopic organisms are expected to be found in ____
almost every location on Earth
The monomers of proteins are _____ _____
amino acids
The smallest unit of an element that cannot be chemically broken down into smaller units is the ___
atom
The number of protons an element has is its _____, whereas the number of electrons will determine ____
atomic number; the type of bond it can form
An organic molecule made up of one or more sugars is a ____
carbohydrate
pH is the measure of
concentration of hydrogen atoms
Which part of an atom forms covalent bonds with other atoms?
electrons in the outermost energy shell
A chemically pure substance that cannot be broken down is a(n) ___
element
A researcher has discovered a new substance. No matter what chemical reactions he subjects this substance to, the substance never breaks down. This substance is most likely a new ___
element
A news item from December 2014 announced that NASA had identified a novel form of bacterial life from Mono Lake in California. Unlike other living organisms, which require carbon, hydrogen, nitrogen, sulfur, oxygen, and phosphorus to survive, this bacterium is able to live and grow without a supply of carbon, hydrogen, nitrogen, sulfur, oxygen, and arsenic. The essential items required by this bacterium (such as nitrogen) are ___
elements
On a NASA mission that was looking for life on Mars, soil samples were taken and measured for the breakdown of nutrients and the production of carbon dioxide gas. Which characteristic of life would this test measure?
energy use
Maintaining a stable internal environment that is separate and distinct from the external environment is called ____.
homeostasis
What part of the cell membrane phospholipid is exposed to the watery interior of the cell? Please choose the correct answer from the following choices, and then select the submit answer button.
hydrophilic head
One of the symptoms of rabies is a fear and avoidance of water. This symptom can be described as a _____ behavior.
hydrophobic
Certain types of radiation can damage DNA. When DNA is damaged, which function is compromised?
information storage
Anything that takes up space and has mass is ____
matter
An amino acid is to a protein as a_____ is to a complex carbohydrate
monosaccharide
Which is NOT a characteristic of a living organism?
movement from place to place
DNA and RNA are examples of ___
nucleic acids
If a person has low levels of phosphorous in his or her blood, phosphorous may be "stolen" from bones to make it available for cellular molecules. Which molecules require phosphorous as part of their structure?
nucleic acids and phospholipids
Which of these contains a monosaccharide as part of its structure? Please choose the correct answer from the following choices, and then select the submit answer button.
nucleotides and carbohydrates
A scientist is looking at a cell's membrane. She notices that the membrane is composed (primarily) of a certain type of macromolecule. These macromolecules are unique in that they are not composed of monomers, but instead resemble "hairpins" with fatty acid tails. This scientist is looking at ____
phospholipids
A protein only infectious agent is a
prion
Which trait is NOT a functional characteristic of all living things?
protect self from predators
A scientist has discovered a new macromolecule in mice. He determines that this macromolecule contains a unique combination of 20 distinct monomers, folds into an intricate three-dimensional shape, and is involved in a distinct chemical reaction. This scientist has likely discovered a ____
protein
An element's identity, its atomic number, depends on the number of _____ it contains
protons
Which functional trait of a living organism is a mule NOT capable of?
reproduction
One argument explaining why viruses are not living is that viruses depend on the cells of other living creatures in order to multiply. Which characteristics of life does this argument use? Select the TWO answers that are correct.
reproduction and growth
Which of these would NOT be considered monomers?
sterols
If a phospholipid bilayer is described as a "sandwich," which part is the bread?
the heads
Which part of a phospholipid is hydrophobic?
the tails
What determines the identity of a particular atom? Select the TWO answers that are correct.
total number of electrons in orbitals;number of protons and number of neutrons in the nucleus
Carbon has unique properties that make it an ideal backbone for life
true
If life is found on other planets, it may or may not use the chemical framework used by life on Earth
true
Water is considered a polar molecule
true
An infectious agent made up of a protein shell that encloses genetic information is a _____
virus