Exam 1 Flashcards
1
Q
T or F
all living organisms are composed of multiple cells?
A
False
some living organisms are single-celled
2
Q
Place the following levels of biological organization in order from smallest to largest: atom, biosphere, cell, ecosystem, molecule, organ, organism, population, tissue.
Which is the smallest level capable of demonstrating all of the characteristics of life?
A
atom molecule cell tissue organ organism population ecosystem biosphere
The Cell
3
Q
Plants use the process of photosynthesis to convert the energy in sunlight to chemical energy in the form of sugar. While doing so, they consume carbon dioxide and water and release oxygen. Explain how this process functions in both the cycling of chemical nutrients and the flow of energy through an ecosystem.
A
Photosynthesis cycles nutrients by converting the carbon in carbon dioxide into sugar, which is then consumed by other organisms. Additionally, the oxygen in water is released as oxygen gas. Photosynthesis contributes to energy flow by converting sunlight into chemical energy, which is then also consumed by other organisms, and by producing heat.
4
Q
What is the domain/kingdom?
A foot-tall organism capable of producing its own food from sunlight
A
Eukarya/Plantae
5
Q
What is the domain/kingdom?
A microscopic, simple, nucleus-free organism found growing in a riverbed
A
Bacteria
6
Q
What is the domain/kingdom?
An inch-tall organism growing on the forest floor that consumes material from dead leaves
A
Eukarya/Fungi
7
Q
What is the domain/kingdom?
A thimble-sized organism that feeds on algae growing in a pond
A
Eukarya/Animalia
8
Q
How does natural selection cause a population to become adapted to its environment over time?
A
On average, those individuals with heritable traits best suited to the local environment produce the greatest number of offspring that survive and reproduce. This increases the frequency of those traits over time. The result is the accumulation of evolutionary adaptations.
9
Q
Best describes the logic of scientific method?
A
If my hypothesis is correct, I can expect certain test results.
10
Q
Why is it difficult to draw a conclusion from an experiment that does not include a control group?
A
Without a control group, you don’t know if the experimental outcome is due to the variable you are trying to test or to some other variable.
11
Q
Distinguish hypotheses from theories in science
A
Hypotheses usually are narrow in scope; theories have broad explanatory power.
12
Q
________ is the core idea that unifies all areas of biology.
A
Evolution
13
Q
Natural Selection
A
Unequal reproductive success
14
Q
Evolution
A
Descent with modification
15
Q
Hypothesis
A
A testable idea
16
Q
Biosphere
A
All life-supporting environments on Earth
17
Q
How can you tell that something is alive?
A
You can tell that something is alive because it has the ability to react to its
environment
18
Q
What are six properties common to all living things?
A
order regulation growth and development energy utilization reproduction evolution.
19
Q
What is the basic organization of life?
A
A cell
20
Q
What are the three domains of life? What organisms does each domain include?
A
bacteria – prokaryotic
archaea - prokaryotic
eukarya – eukarya – plantae, fungi, animalia, and protista
21
Q
What is the theory that unifies biology as a science?
A
Evolution
22
Q
Describe the basic steps in the scientific method, using an example. Why are controls
necessary in the scientific method?
A
The basic steps in the scientific method are observations, question, hypothesis,
prediction, and test. An example of the scientific method is noticing that your car
won’t start, you think it may be your battery, you try jumping your car and you
either realize it is the battery.
Controls are necessary in the scientific method so that they can cancel out any
effects of all variables other than the one being tested.
23
Q
What is the difference between a hypothesis and a theory?
A
A theory is a hypothesis
that has been tested multiple times.
24
Q
An atom can be changed into an ion by adding or removing?
A
Electrons
25
An atom can be changed into a different isotope by adding or removing?
Neutrons
26
If you change the number of ______ the atom becomes a different element.
Protons
27
A nitrogen atom has 7 protons, and the most common isotope of nitrogen has 7 neutrons. A radioactive isotope of nitrogen has 9 neutrons. What are the atomic numbers and mass numbers of the stable and radioactive forms of nitrogen?
Nitrogen - 14
atomic number of 7
mass of 14
radioactive nitrogen - 16
atomic number of 7
mass of 16
28
Why are radioactive isotopes useful as tracers in research on the chemistry of life?
Organisms incorporate radioactive isotopes of an element into their molecules just as they do the nonradioactive isotopes, and researchers can detect the presence of the radioactive isotopes.
29
A sulfur atom has 6 electrons in its third (outermost) shell, which can hold 8 electrons. As a result, it forms _____ covalent bonds with other atoms.
2
30
What is chemically nonsensical about this structure?
| H-C=C-H
Each carbon atom has only three covalent bonds instead of the required four.
31
Is this a chemical reaction?
| Ice melts to form liquid water
NO
32
A polar molecule is...
Slightly negative at one end and slightly positive at the other end.
33
Explain how the unique properties of water result from the fact that water is a polar molecule.
The positive and negative poles cause adjacent water molecules to become attracted to each other forming hydrogen bonds. The properties of water such as cohesion, temperature regulation, and water's ability to act as a solvent.
34
A can of cola consists mostly of sugar dissolved in water, with some carbon dioxide gas that makes it fizzy and makes the pH less than 7. Describe the cola using the following terms: solute, solvent, acidic, aqueous solution.
The cola is an aqueous solution, with water as the solvent, sugar as the main solute, and CO2 making the solution acidic.
35
The smallest unit of matter that retains the properties of an element.
Atom
36
The smallest structural and functional unit of an organism
Cell
37
All the organisms inhabiting and potentially interacting in a particular area
Community
38
The global ecosystem; the entire portion of Earth inhabited by life; all of life and where it lives.
Biosphere
39
All the organisms in a given area
Ecosystem
40
List properties common to all living things
they are complex and organized
they grow and produce
they respond to stimuli
the acquire materials and use energy (metabolism)
they use DNA to store hereditary information
they have adaptations to their environment
41
The process of keeping internal conditions such as temperature constant in an organism
homeostasis
42
A substance that can't be broken down into another substance by ordinary means
Element
43
The three components of an atom
Protons +
Neutrons are neutral
Electrons -
44
These orbit around the protons and neutrons in the nucleus of the atom
Electrons
45
Equals the number of protons or electron in the element
Atomic number
46
Equals the number of protons plus its number of neutrons
Atomic mass
47
____ can donate an electron to another ____ or accept an electron from another ____ to become an ion
Atom
48
An attraction between two ions with opposite electrical charges. The electrical attraction of the opposite charges holds the ions together.
Ionic bond
49
An attraction between atoms that share one or more pairs of outershell electrons
Covalent bond
50
_____ make and break chemical bonds to form new substances.
Chemical bondS
51
A molecule containing polar covalent bonds
Polar molecule
52
The shared electrons that form the bond are shared unequally, creating partial positive and partial negative charges at opposite ends of the molecule
Polar covalent bond
53
A polar molecule composed of two hydrogen atoms and one oxygen atom
water
54
A weak chemical bond formed when a partially positive hydrogen atom from one polar molecule is attracted to the partially negative atom in another molecule
Hydrogen bond
55
What are water's unique properties?
```
high specific heat
good solvent
cohesive and adhesive
polar
ice floats
```
56
Water-loving; pertaining to polar or charged, molecules, which are soluble in water
hydrophilic
57
Water-fearing; pertaining to nonpolar molecules which do not dissolve in water
hydrophobic
58
What makes a molecule hydrophilic or hydrophobic?
Whether the compound is polar(uneven distribution of charge) or nonpolar (even distribution of charge).
59
Any solution in which water (H2O) is the solvent
Aqueous
60
Any aqueous solution which has a pH < 7.0
Acidic solution
61
An aqueous solution with a pH greater than 7.
basic solution
62
A measure of the relative acidity of a solution ranging in value from 0 to 14.
pH scare
63
______ are molecules that minimize changes in pH in an organism.
Buffers
64
What are the four major classes of large molecules?
Carbohydrates
lipids
proteins
nucleic acids
65
______ are composed of smaller subunits (monomers)
Large molecules (polymers)
66
Two subunits covalently bond to each other through the loss of a water molecule in a_______
dehydration reaction
67
The opposite of a dehydration reaction where a molecule of water is added to break the covalent bond
hydrolysis
68
______ contain both carbon and hydrogen while _____ do not
Organic molecules
| inorganic molecules
69
Include single sugars (monosaccharides) and molecules made of two or more sugar subunits (disaccharides, polysaccharides)
Carbohydrates
70
The function of _____ is to store energy
disaccharides
71
A carb polymer consisting of many monosaccharides linked by covalent bonds
polysaccharide
72
What are the two main types of polysaccharides?
storage and structural
73
A large polysaccharide composed of many glucose monomers linked into cable-like fibrils that provide structural support in plant cell walls. Cellulose cannot be digested by animals.
cellulose
74
A tough, protective, semitransparent substance, primarily a nitrogen-containing polysaccharide, forming the principal component of arthropod exoskeletons and the cell walls of certain fungi.
Chitin
75
Describe the “anatomy” of an atom
an atom consists of subatomic particles including protons, electrons, and neutrons. The atom has a central core called the nucleus – I have always thought of the nucleus as the “brain” or “heart” of an atom. The reaction between protons and electrons causes levels of electrical charge and, in my mind, I picture them moving around as if in a lighting and thunder storm.
76
the number of protons in an atom which determines the element
atomic number
77
a subatomic particle with a single unit of positive electrical charge
proton
78
is electrically neutral or has no electrical charge
neutron
79
a subatomic particle with a single unit of negative electrical charge
electron
80
forms of an element that differ in mass
isotope
81
What are four differences between prokaryotic and eukaryotic cells?
The four differences between prokaryotic and eukaryotic cells are: Prokaryotes are older, usually smaller and simpler in structure. The biggest difference is that eukaryotic cells have organelles.
82
Name three differences between animal and plant cells.
Three differences between animal and plant cells are: Plant cells have chloroplasts, a protective cell wall outside the plasma membrane, and plant cells have a central vacuole.
83
The ________ of a cell separates the cell from its environment, is composed of phospholipids and proteins. Phospholipids spontaneously form a double layer because the head is hydrophilic and the tail is hydrophobic.
plasma membrane
84
The function of the ________ is to separate the living cell from its nonliving environment.
plasma membrane
85
An ________ is a membrane-enclosed structure with a specialized function within the eukaryotic cell.
organelle
86
provides protein synthesis
ribosomes
87
responsible for cellular respiration
mitochondria
88
helps form the endomembrane system and produces proteins and lipids
Endoplasmic reticulum
89
stacks of membranous sacs that modify, store, and ship products of the endoplasmic reticulum
Golgi apparatus
90
promote movement by a coordinated back and forth motion
cilia
91
membrane-enclosed sac that contains digestive enzymes and breaks down food so that the cell can use it
Lyosomes
92
The functions of the _________ are to provide mechanical support and maintain shell shape and help the cells change shape.
cytoskeleton
93
The _________ contains several types of fibers made from different types of protein.
cytoskeleton
94
What is the difference between kinetic energy and potential energy?
Kinetic energy is created by movement and potential energy is energy that is stored but not being used.
95
Is chemical energy considered kinetic or potential energy?
Chemical energy is considered potential energy because it is stored.
96
What is ATP
adenosine triphosphate.
97
The function of ATP
act as an energy source for cells.
98
speeds up the chemical reaction
Enzymes
99
factors that affect enzyme activity include ____ and ____
temperature and pH
100
the enzyme choosing which molecules it wants to select
Substrate
101
embraces the substrate and catalyzes the reaction
Active site
102
What is diffusion
Diffusion is the random movement of molecules spreading out into open space. An example of diffusion would be removing a cap from any type of container allowing the molecules to escape. Another example would be “diffusers” that you can buy in the store to help your house smell nice. They use the same concept.
103
is the diffusion of water across a permeable membrane
osmosis
104
If an animal cell is in a hypotonic solution, what happens to the cell?
The cell fills with water, swells, and could burst.
105
What is the difference between endocytosis and exocytosis?
Endocytosis is when cells expel proteins and endocytosis is when the cell takes material in.
106
Monomers are joined together to form larger polymers through _____ reactions
dehydration
107
Polymers are broken down into the monomers that make them up through the chemical reaction called _______
hydrolysis
108
_______ includes polysaccharides, monosaccharides, and disaccharides
carbohydrates
109
One molecule of dietary fat is made by joining three molecules of _____to one molecule of ______
fatty acid
| glycerol
110
____ contains the maximum number of hydrogens along hydrocarbon tails
saturated fats
111
humans and other animals cannot digest wood because they _____
lack the enzyme needed to break down cellulose
112
changing one amino acid within a protein could change what about a protein
the primary structure
the shape of the protein
the function of the protein
113
Where within the overall three-dimensional shape of a protein would you most likely find hydrophobic amino acids
the interior of a protein, far from the watery environment
114
a shortage of phosphorus in the soil would make it especially difficult for a plant to manufacture
DNA
115
A glucose molecule is to ____ as a ______ is to a nucleic acid
starch
| nucleotide
116
three similarities between DNA and RNA
both are polynucleotides
both have the same phosphate group along the backbone
both use A, C, and G bases
117
three differences between DNA and RNA
DNA uses T while RNA uses U as a base
the sugar differs between them
DNA is usually double-stranded while RNA is usually single-stranded
118
if you wanted to film the movement of chromosomes during cell division, the best choice for a microscope would be a ______
light microscope because the specimen must be kept alive
119
if a section of a large spherical cell is 0.3 mm in diameter, the nucleus is about one-fourth as wide. what is the diameter of the nucleus in micrometers
about 0.075 mm
120
if you are looking at an unknown cell what might you see that would tell you whether the cell is prokaryotic or eukaryotic
a nucleus
121
how do the words fluid mosaic decribe the structure of a membrane
a membrane is fluid because its components are not locked into place. It's mosaic because it contains a variety of embedded proteins
122
Includes rough ER, smooth ER and the Golgi apparatus
endomembrane system
123
The ER has two distinct regions that differ in structure and function. Lipids are synthesized within the ______, and proteins are synthesized within the _______
smooth ER
| rough ER
124
two similarities in the structure or function of chloroplasts and mitochondria
both organelles use membranes to organize enzymes
| both provide energy to the cell
125
two differences in the structure or function of chloroplasts and mitochondria
chloroplasts us pigments to capture energy from sunlight in photosynthesis - mitochondria release energy from glucose using oxygen in cellular resperation
chloroplasts are only in photosynthetic plants and protists whereas mitochondria are in almost all eukaryotic cells
126
the function of ribosomes
protein synthesis
127
the function of microtubules
movement
128
the function of mitochondria
cellular respiration
129
the function of chloroplasts
photosynthesis
130
lysosomes
digestions
131
what order represents the flow of genetic information from the DNA through the cell
```
nucleus
nuclear pores
ribosomes
rough ER
Golgi apparatus
```
132
the bonds that join fatty acids to glycerol are ______ bonds and they are formed by ________ reactions
covalent
| dehydration
133
steriods are _____
lipids
134
_____ is made of chains of amino acids
protein
135
______ form proteins by joining covalent bonds call peptide bonds, in dehydration reactions
amino acids
136
a protein's _______ determines how it will function
conformation (3-D shape)
137
_____ is when a protein unravels and loses its normal conformation
denaturation
138
______ can happen in response to changes in the physical and chemical conditions in the environment like temperature or pH
denaturation
139
what are the two types of nucleic acids
DNA (deoxyribonucleic acid) and RNA (ribonucleic Acid)
140
______ are made from subunits called nucleotides
nucleic acids
141
____ is made of two strands of nucleotides
DNA
142
_____ is made of only one strand of nucleotides
RNA
143
what is the molecular structure of nucleotides
they have a phosphate group
a base
and a sugar
144
All ______ are composed of one or more cells
organisms
145
all ______ are surrounded by a plasma membrane, use DNA to store genetic material, contain cytoplasm, and obtain energy and nutrients from their environment
cells
146
______ have hydrophilic "heads' and hydrophobic "tails" and they arrange into a double layer when surrounded by water
phospholipid molecules
147
The proteins embedded in the phospholipid bilayer can have various functions depending on their structure, including _______
transport proteins, receptor proteins, and recognition proteins
148
_____ exhibit selective permeability, allowing certain molecules to pass but not others.
Plasma membranes
149
_____ cells are smaller, simpler and lack a nucleus, lack all organelles besides ribosomes
prokaryotic
150
_____ cells are larger, more complex, have a nucleus and membrane-bound organelles
eukaryotic
151
bacteria and archaea are _____ cells
prokaryotic
152
plants, animals, fungi, and protists are _____ cells
eukaryotic
153
____ are protein factories of the cell, manufacturing proteins according to the instructions in DNA
ribosomes
154
________ manufactures and processes lipids and detoxifies waste products
endoplasmic reticulum
155
The ______ is the "shipping and receiving" center of the cell, sorting, altering, and packaging molecules
Golgi apparatus
156
_____ and ____ convert energy from one form to another
chloroplasts and mitochondria
157
_____ are vesicles filled with digestive enzymes that break down old organelles or extra molecules for recycling
lysosomes
158
_____ regulate water and store substances
vacuoles
159
_____ is a network of protein fibers that helps maintain cell shape and plays a role in cell movement, organelle movement, and cell division
cytoskeleton
160
_____ is the capacity to perform work, or to move matter in a direction it would not move if left alone
energy
161
_____ and ____ are the two main forms of energy
kinetic and potential
162
first law of thermodynamics
Energy can be changed from one form to another, but it cannot be created or destroyed.
163
second law of termodynamics
in all energy exchanges, if no energy enters or leaves the system, the potential energy of the state will always be less than that of the initial state.
164
______ is a measure of disorder, or randomness. One form of disorder is heat, which is random molecular motion.
entropy
165
____ is an ending material in a chemical reaction
product
166
____ is a starting material in a chemical reaction
reactants
167
all reactions require an initial input of energy called the energy of _____
activation
168
_____ is the total of all the chemical reactions in an organism
metabolism
169
____ is the part of an enzyme molecule where a substrate molecule attaches typically a pocket or groove on the enzyme's surface
active site
170
____ is a protein that serves as a biological catalyst, changing the rate of a chemical reaction without itself being changed in the process
enzyme
171
____ a specific substance on which an enzyme acts or a surface in which an organism lives
substrate
172
enzymes speed up reactions by _______
lowering the energy of activation
173
___ is a substance that dissolved in a solution
solute
174
____ is a liquid consisting of a homogeneous mixture of two or more substances
solution
175
____ is the dissolving agent in a solution
solvent
176
____ an increase or decrease in the density of a chemical substance within a given region
concentration gradient
177
diffusion, osmosis, and facilitated diffusion are all type of _______
passive transport
178
A _____ solution has the greater concentration of solutes
hypertonic
179
A ___ solution is the one with the lower concentration of solutes
hypotonic
180
_____ solution has the same solute concentration as another solution
isotonic
181
____ is the spontaneous movement of particles of any kind down a concentration gradient
diffusion
182
_____ is the passage of a substance across a biological membrane down its concentration gradient aided by specific transport proteins
facilitated diffusion
183
___ is the diffusion of water across a selectively permeable membrane
osmosis
