65 terms

Cont. Bio 103 Ch 1 & 2

What is homeostasis?
a relatively constant internal environment (equilibrium)
The main function of protein in a cell is to..
play structural, enzymatic, and transport roles to in a cell
False about nucleic acid
The rungs of a DNA double helix are composed of complementary base pairs that are held together by covalent bonds.
True about nucleic acid
The handrails of the DNA double helix are composed of a sugar-phosphate backbone.

The base cytosine is complementary to the base guanine.

Nucleic acids are composed of monomer nucleotides, each composed of a sugar, a nitrogenous base, and a phosphate.
What organelle is found in plant cells but not animal cells?
What cells are prokaryotic?
bacteria cells
In a neutral solution
hydrogen ions is equal to the concentration of hydroxide ions
two or more atoms held together by a covalent bond
hydrogen bond
A hydrogen atom with a net positive charge is attracted to an oxygen atom with a net negative charge.
What name is given to the bond between water molecules?
hydrogen bond; A hydrogen atom with a net positive charge is attracted to an oxygen atom with a net negative charge.
Each water molecule is joined to _____ other water molecules by ____ bonds.
a water molecule is joined to four other water molecules by hydrogen bonds.
The unequal sharing of electrons within a water molecule makes the water molecule _____.
The tendency of an atom to pull electrons toward itself is referred to as its _____.
In this molecule, what type of bond is found between the oxygen and hydrogens?
polar covalent
The transfer of a hydrogen atom from one water molecule to another is referred to as
equation for the dissociation of water
H2O + H2O <==> H3O+ + OH-
What is the charge on a hydronium ion?
What is the charge on a hydroxide ion?
What determines the types of chemical reactions that an atom participates in?
the number of electrons in the outermost electron shell
Atoms with the same number of protons but with different electrical charges _____.
are different ions
In salt, what is the nature of the bond between sodium and chlorine?
An ionic bond involves _____.
an attraction between ions of opposite charge
What type of bond joins the carbon atom to each of the hydrogen atoms?
single (nonpolar) covalent
If a DNA double helix is 100 nucleotide pairs long and contains 25 adenine bases, how many guanine bases does it contain?
100 nucleotide pairs are a total of 200 nucleotides. Because of base pairing, if there are 25 adenine there must also be 25 thymine. This leaves 200-50 = 150 nucleotides to be divided evenly between guanine and cytosine.
The two strands of a DNA double helix are held together by _____ that form between pairs of nitrogenous bases.
hydrogen bond
A nucleotide is composed of a(n) _____.
phosphate group, a nitrogen-containing base, and a five-carbon sugar
Which of the following subatomic particles is present in the same number in all atoms of a particular element?
True or false: All phospholipids contain fatty acids, glycerol, and a phosphate molecule.
Which of the following terms describes a lipid molecule that is composed of four fused carbon-containing rings?
_____ are surface appendages that allow a bacterium to stick to a surface.
What is the function of a bacterium's capsule?
Where is a bacterial cell's DNA found?
nucleon region
In a bacterium, where are proteins synthesized?
What name is given to the rigid structure, found outside the plasma membrane, that surrounds and supports the bacterial cell?
cell wall
The _____ is the bacterial structure that acts as a selective barrier, allowing nutrients to enter the cell and wastes to leave the cell.
plasma membrane
The structure that regulates the passage of material into and out of this bacterial cell is indicated by the letter _____.
plasma membrane
organelle that contains most of a cell's DNA.
Which of these organelles carries out cellular respiration?
Mitochondria convert the chemical energy of organic molecules to chemical energy in the form of ATP.
Which of these is the double membrane that encloses the nucleus?
nuclear envelope
The _____ is composed of DNA and protein.
Ribosomal subunits are manufactured by the _____.
_____ are the sites of protein synthesis.
Which of these manufactures cellular membranes by adding membrane proteins and phospholipids to its own membrane?
rough endoplasmic reticulum
The _____ is a selective barrier, regulating the passage of material into and out of the cell.
plasma membrane
Where is calcium stored?
smooth endoplasmic reticulum
Which of these structures stores, modifies, and packages products?
golgi apparatus
Which of these are hollow rods that shape and support the cell?
are rods that also play a role in organelle movement.
_____ is/are identical in structure to centrioles.
basal bodies
Which of these organelles produces H2O2 as a by-product?
Which of these provides the cell with structural support?
Microfilaments are a component of the cytoskeleton.
The plasma membrane is often described as a fluid mosaic of lipids and proteins. What does this mean?
Proteins and lipids within the phospholipid bilayer are free to move laterally within the membrane.
The organelle that is responsible for cellular recycling is the
Lysosomes contain digestive enzymes that help degrade food and worn out organelles for recycling within a cell.
Which organelle is the location of the synthesis of testosterone?
smooth endoplasmic reticulum
The cellular structures that synthesize proteins are themselves produced in
the nucleolus
The cell wall of plant cells is made of
a polysaccharide of glucose called cellulose.
Individuals of the same species vary from one another. Some are well-suited to their environment and survive, while others are not as well-suited and die. The less-successful variants are eventually lost from the population. This overall concept is called
natural selection
The three structures found in a plant cell, but not in an animal cell, are
cell wall, chloroplasts, and central vacuole.
The DNA-containing region of this bacterial ce
The nucleoid region
The structure that regulates the passage of material into and out of this bacterial cell is indicated by the letter _____.
plasma membrane
True or false: A large sample size decreases the likelihood that an experimental result will be significant.
Testing "if...then" predictions in order to determine the validity of a hypothesis is an example of
deductive reasoning
Which of the following would involve following one group of individuals as you measure exposure to a treatment and disease prevalence over time?
cohort study