Biology Test 1 Flashcards
1
Q
What is the scientific method?
A
A method of research with defined steps: experiments and careful observation.
2
Q
What are the steps of the scientific method?
A
- Identify a problem
- Hypothesis
- Prediction
- Experiment
- Result
- Conclusion
3
Q
What is a hypothesis?
A
A suggested explanation for an event that can be tested.
4
Q
What does it mean for something to be falsifiable?
A
Able to be disproved by experimentation.
5
Q
What is a scientific theory?
A
A thoroughly tested and confirmed explanation for observations or phenomena.
6
Q
What is a scientific law?
A
A description, often in the form of a mathematical formula, for the behavior of some aspect of nature under certain conditions.
7
Q
What is inductive reasoning?
A
Logical thinking that uses related observations to arrive at a general conclusion.
8
Q
What is deductive reasoning?
A
A form of logical thinking that uses a general statement to predict specific results.
9
Q
What is descriptive science?
A
Science that aims to observe, explore, and find things without tests, such as anatomy, art, or history.
10
Q
What is hypothesis-based science?
A
Science that starts with a specific explanation that is then tested.
11
Q
What is a variable in an experiment?
A
Part of an experiment that is subject to change by the tester.
12
Q
What is a control in an experiment?
A
Part of an experiment that does not change.
13
Q
What is a peer-reviewed article?
A
A scientific report that is reviewed by a scientist’s colleagues before publication.
14
Q
What are the properties of life?
A
- Order
- Sensitivity or response to stimuli
- Reproduction
- Adaptation
- Growth and development
- Homeostasis
- Energy processing
- Evolution
15
Q
What does ‘order’ mean in the properties of life?
A
To be able to be put in categories.
16
Q
What is sensitivity to stimuli?
A
Responding to the world and outside forces, allowing for survival through attraction and avoidance.
17
Q
What is reproduction?
A
Recreation of organisms: life creates life.
18
Q
What is adaptation?
A
Organisms respond and reflect conditions that they’re in.
19
Q
What is growth and development?
A
Change/cycle is the process of maturation.
20
Q
What is homeostasis?
A
Self-regulating process for organisms to maintain stability and adjust to conditions that are best for its stability.
21
Q
What is energy processing?
A
Needs and uses energy to achieve needs like plants with photosynthesis and mammals with mitochondria.
22
Q
What is evolution?
A
Breeding and developing by adapting new strengths for survival.
23
Q
What are the organizations of life?
A
- Atom
- Molecule
- Organelle
- Cell
- Tissue
- Organ
- Organ system
- Organism
- Population
- Community
- Ecosystem
- Biosphere
24
Q
What is an atom?
A
Smallest unit of an element/matter with a dense nucleus surrounded by negative electrons.
25
What is a molecule?
Chemical structure of at least 2 atoms held together by a chemical bond.
26
What is a macromolecule?
Large molecule formed by joining smaller organic molecules together.
27
What is an organelle?
A membrane-bound compartment or sac within a cell.
28
What is a cell?
Smallest fundamental unit of structure and function in living things.
29
What is a prokaryote?
A unicellular organism that has no nucleus or membrane-bound organelles.
30
What is a eukaryote?
A cell that contains a nucleus and membrane-bound organelles.
31
What is tissue?
Groups of similar cells with the same function.
32
What is an organ?
Structure formed by tissues operating to perform common functions.
33
What is an organ system?
Group of functionally related organs that work together to perform their specific function.
34
What is an organism?
An individual living entity made of one or more cells.
35
What is a population?
All of the individuals of a species that live in the same area.
36
What is a community?
A set of populations inhabiting a particular area.
37
What is an ecosystem?
All living things in a particular area together with the abiotic, nonliving parts of that environment.
38
What is a biosphere?
Collection of all ecosystems on earth, both living and non-living.
39
What is the difference between a prokaryote and a eukaryote?
A prokaryote is unicellular and has no membrane-bound organelles, while a eukaryote is made of one or more cells that do have membrane-bound organelles.
40
What is an element?
A substance that cannot be broken down into simpler substances or chemically transformed.
41
What does an atom contain?
Nucleus, protons, neutrons, electrons.
42
What is the nucleus of an atom?
Dense center of an atom made of protons and neutrons.
43
What are neutrons?
A particle with no charge in an atom's nucleus with a mass of 1.
44
What are protons?
A positively charged particle in the nucleus of an atom with a mass of 1 and a charge of 1.
45
What are electrons?
Negatively charged particles outside an atom's nucleus in orbit with no mass and only charge.
46
What is atomic number?
The number of protons in an atom, determining what the element is.
47
What is mass number?
The sum of the number of neutrons and protons in an atomic nucleus.
48
What is a chemical bond?
Interactions between two or more atoms that form molecules.
49
What is an ion?
An atom that does not contain an equal number of protons and electrons and has a net charge.
50
What is a cation?
Positive ion formed by losing electrons.
51
What is an anion?
Negative ion formed by gaining electrons.
52
What is an ionic bond?
Chemical bond formed by ions of opposite charges.
53
What is a covalent bond?
Strong bond between two or more of the same or different elements that share electrons.
54
What is a polar covalent bond?
Where electrons are pulled back and forth creating a slightly positive charge on one side and a negative charge on the other.
55
What is a non-polar covalent bond?
Where electrons are equally shared between atoms, meaning no partial charges.
56
What is a hydrogen bond?
A weak bond between partially positively charged hydrogen atoms and partially negatively charged elements or molecules.
57
What is a van der Waals interaction?
A weak attraction or interaction between molecules caused by slightly charged atoms.
58
What are the types of chemical bonds?
Ionic, covalent (polar and non-polar), hydrogen, van der Waals interaction.
59
What are the properties of water?
Hydrophilic, hydrophobic, solvent, cohesion, surface tension, adhesion.
60
What does hydrophilic mean?
Substances that dissolve in water or are water loving.
61
What does hydrophobic mean?
Substances that do not dissolve in water or are water fearing.
62
What is a solvent?
Substances capable of dissolving another substance, such as water.
63
Why is water a good solvent?
Its polar-covalent bond takes over other ions, causing dissolving.
64
What is cohesion?
Intermolecular forces between water molecules caused by the polar nature of water.
65
What is surface tension?
The cohesive force at the surface of a body of liquid that prevents the molecules from separating.
66
What is adhesion?
When water molecules are attracted to molecules of different substances.
67
What is an acid?
A substance that donates hydrogen ions, which lowers its pH.
68
What is a base?
A substance that absorbs hydrogen ions, which raises its pH.
69
What is the pH scale?
A 0-14 scale with 0 to 7 being acidic and 8 to 14 being basic.
70
What are carbohydrates?
Biological macromolecules with a carbon-hydrogen-oxygen ratio of 1:2:1, serving as energy sources and structural support in cells.
71
What are the types of carbohydrates?
Monosaccharides, disaccharides, polysaccharides.
72
What are monosaccharides?
A single unit or monomer of carbohydrates.
73
What are disaccharides?
Two monosaccharides linked by a glycosidic bond to form a carbohydrate.
74
What are polysaccharides?
A long chain of monosaccharides connected by glycosidic bonds that can be branched, unbranched, or complex carbs.
75
What are the types of polysaccharides?
Starch, glycogen, cellulose, chitin.
76
Which polysaccharides are for storage and which are for structure?
Storage: starch and glycogen
Structure: cellulose and chitin.
77
What are lipids?
A class of macromolecules that are non-polar and insoluble in water.
78
What are the types of lipids?
Fats, phospholipids, steroids.
79
What is fat?
A lipid molecule composed of 3 fatty acids and a glycerol, typically existing in a solid form at room temperature.
80
What are the types of fats?
Saturated and unsaturated fatty acids.
81
What is another name for fat?
Triglycerides.
82
What are saturated fatty acids?
A long chain of hydrocarbons with a single covalent bond in the carbon chain.
83
What are unsaturated fatty acids?
A long-chain hydrocarbon that has one or more double bonds in the hydrocarbon chain.
84
What are steroids?
A type of lipid composed of four fused hydrocarbon rings with various functional groups attached.
85
What are phospholipids?
A major constituent of the cell membrane comprised of two fatty acids and a phosphate group attached to a glycerol backbone.
86
What are proteins?
Biological macromolecules composed of one or more amino acid chains.
87
What are the types of proteins?
Enzymes, hormones, amino acids, polypeptides.
88
What are enzymes?
A catalyst in a biochemical reaction that is usually a complex or conjugated protein.
89
What are hormones?
Chemical signaling molecules, usually a protein or steroid secreted by an endocrine gland or group of cells.
90
What are amino acids?
Monomers of proteins that contain nitrogen.
91
What are polypeptides?
Long chains of amino acids that make proteins.
92
What are organic molecules?
Molecules that contain carbon bound to hydrogen, typically found in living or previously living things.
93
What are nucleic acids?
Macromolecules containing hydrogen, oxygen, nitrogen, carbon, and phosphorus.
94
What is deoxyribonucleic acid (DNA)?
A double-stranded polymer of nucleotides that carries the hereditary information of cells.
95
What are nucleotides?
Monomers of nucleic acids that contain one pentose sugar, a phosphate group, and a nitrogenous base.
96
What are the two main types of cells?
Prokaryotes and eukaryotes.
97
Which part of the phospholipid is hydrophobic and which part is hydrophilic?
The head is hydrophilic and the tails are hydrophobic.
98
What is cytoplasm?
The substance inside the cell that contains everything but the nucleus and nuclear envelope.
99
What is cytosol?
Gel-like material of the cytoplasm in which cell structures are suspended.
100
What is the cytoskeleton?
A network of protein fibers that holds the cell together, helps the cell keep its shape, and aids in movement.
101
What comprises the cytoskeleton?
Microfilaments, intermediate filaments, microtubules.
102
What are flagella?
Whiplike tails found in one-celled organisms to aid in movement.
103
What are cilia?
Short, hair-like structures that extend from the plasma membrane in large numbers and are used to move an entire cell or substances along a cell's outer surface.
104
What is the endomembrane system?
The group of organelles and membranes in eukaryotic cells that work together to modify, package, and transport lipids and proteins.
105
What makes up the endomembrane system?
Nucleus, endoplasmic reticulum, Golgi apparatus, lysosomes, vesicles, and vacuoles.
106
What is the nucleus?
The cell organelle that houses the cell's DNA and directs the making of ribosomes and proteins.
107
What is the nuclear envelope?
The double membrane structure that makes the outside of the nucleus.
108
What are chromosomes?
Structures inside the nucleus that comprise chromatin containing DNA.
109
What is chromatin?
Protein-DNA complex that serves as chromosomes' building material.
110
What is the nucleolus?
Dark body inside a nucleus that makes ribosomes and ribosomal subunits.
111
What is the endoplasmic reticulum?
A series of interconnected membranes that modify proteins and synthesize lipids.
112
What is rough ER?
Ribosome-studded endoplasmic reticulum that modifies proteins.
113
What is smooth ER?
Endoplasmic reticulum with no ribosomes on the surface that synthesizes lipids, carbohydrates, and steroid hormones.
114
What is the Golgi apparatus?
The eukaryotic organelle that acts as the postal system of the cell, sorting, tagging, and packaging lipids and proteins.
115
What are lysosomes?
Organelles in animal cells that are the digestive component, breaking down proteins, polysaccharides, lipids, nucleic acids, and worn-out organelles.
116
What is a vesicle?
A small membrane-bound sack that is storage and transport in cells.
117
What is a vacuole?
Larger membrane-bound organelle used for storage of food, water, or waste that can't fuse with other organelles.
118
What are ribosomes?
Cellular structures that synthesize proteins.
119
What are mitochondria?
Organelles responsible for cellular respiration that produce ATP, the cell's main energy source.
120
What are peroxisomes?
Small, round organelles that contain hydrogen peroxide and oxidize and break down fatty and amino acids, detoxifying poisons.
121
What is a cell wall?
A rigid layer of nonliving material that surrounds the cells of plants and some other organisms, protecting the cell and maintaining its shape.
122
What are chloroplasts?
Organelles that synthesize photosynthesis and are the site of plant cell's carbon fixation, containing chlorophyll.
123
What is the central vacuole?
A water reservoir, storage compartment, and site for macromolecule degradation in plant cells.
124
What is the extracellular matrix?
Material, primarily collagen, glycoproteins, and proteoglycans, secreted from animal cells that holds cells together as a tissue.
125
What is the plasma membrane?
A phospholipid wall found in both prokaryotes and eukaryotes that regulates the passage of molecules, ions, and water.
126
What is the fluid mosaic model?
Model of plasma membrane structure made up of phospholipids, cholesterol, proteins, and glycolipids.
127
What is selective permeability?
Characteristics of a membrane that allows some substances through but not others.
128
What is passive transport?
The simplest method of transport in cells that does not require energy.
129
What is a concentration gradient?
A difference in the concentration of a substance from high concentration to low across a distance.
130
What are the processes of passive transport?
Diffusion and osmosis.
131
What is diffusion?
Passive transport process of low molecular weight material down its concentration gradient.
132
What is facilitated transport?
A process by which material moves down a concentration gradient using integral membrane proteins.
133
What is osmosis?
The transport of water through a semipermeable bilayer membrane from high water concentration to low water concentration.
134
What is a solvent?
A substance capable of dissolving.
135
What is a solute?
A substance that is dissolved in a solution.
136
What is tonicity?
The amount of solute in a solution.
137
What is osmolarity?
The total amount of substances dissolved in a specific amount of solution.
138
What is isotonic?
When the extracellular fluid has the same osmolarity as the fluid inside the cell.
139
What is hypotonic?
Extracellular fluid with lower osmolarity than inside the cell.
140
What is hypertonic?
Extracellular fluid with higher osmolarity than inside the cell.
141
What is active transport?
Method of transporting material that does require energy.
142
What is an electrochemical gradient?
The required gradient produced by the combined forces of the electrical gradient and chemical gradient.
143
What are the types of active transport?
Endocytosis and exocytosis.
144
What is endocytosis?
Active transport process that moves substances, including fluids and particles into cells.
145
What is exocytosis?
Active transport process that passes material out of a cell.
146
What is metabolism?
All the chemical reactions that take place inside cells, including those that use energy and those that release energy.
147
What is anabolic metabolism?
Describes the pathway that requires a net energy input to synthesize complex molecules from simpler ones.
148
What is catabolic metabolism?
Describes the pathway in which complex molecules are broken down into simpler ones, yielding energy as an additional product.
149
What is thermodynamics?
Energy can be transferred or transformed, but it cannot be created or destroyed.
150
What is heat energy?
The energy transferred from one system to another that does not work.
151
What is light energy?
A type of kinetic energy that comes from electromagnetic radiation.
152
What is chemical energy?
Energy stored in the bonds of chemical compounds, which may be released during a chemical reaction.
153
What is kinetic energy?
The type of energy associated with objects in motion.
154
What is potential energy?
The type of energy that refers to the potential to do work.
155
What is glycolysis?
Covalent bond between carbons that hold potential energy, broken during cellular respiration to release energy.
156
What is an exergonic reaction?
Describes a chemical reaction that results in products with lower energy than the reactants.
157
What is chemical energy?
Energy stored in the bonds of chemical compounds, which may be released during a chemical reaction, often in the form of heat.
158
What is potential energy?
The type of energy that refers to the potential to do work, such as an unused battery or a ball at the top of a hill.
159
What is glycolysis?
Covalent bond between carbons that hold potential energy that are then broken during cellular respiration and release energy through kinetic energy.
160
What does exergonic describe?
A chemical reaction that results in products with less chemical potential energy than the reactants, plus the release of free energy.
161
What does endergonic describe?
A chemical reaction that results in products that store more chemical potential energy than the reactants.
162
What is an enzyme?
A molecule that catalyzes a biochemical reaction.
163
What is a substrate?
A molecule on which the enzyme acts.
164
What is an active site?
A specific region on the enzyme where the substrate binds.
165
What is competitive inhibition?
A mechanism of enzyme activity regulation in which a molecule other than the enzyme's substrate is able to bind the active site and prevent the substrate itself from binding.
166
What is non-competitive inhibition?
A mechanism of enzyme activity regulation in which a regulatory molecule binds to a site other than the active site and prevents the active site from binding the substrate.
167
What is allosteric inhibition?
The mechanism for inhibiting enzyme action in which a regulatory molecule binds to a second site (not the active site) and initiates a conformational change in the active site, preventing binding with the substrate.
168
What is feedback inhibition?
A mechanism of enzyme activity regulation in which the product of a reaction or the final product of a series of sequential reactions inhibits an enzyme for an earlier step in the reaction series.
169
What is adenosine triphosphate (ATP)?
The cell's energy currency. Triphosphate means three phosphates. So, has an Adenine, nucleic acid, and 3 triphosphates.
170
What is glycolysis?
The process of breaking glucose into two three-carbon molecules with the production of ATP and NADH.
171
What is aerobic respiration?
Oxygen is the final electron acceptor (Kreb's Cycle).
172
What is anaerobic respiration?
The use of electron acceptor other than oxygen to complete metabolism using electronic transport-based chemiosmosis.
173
What is the citric acid cycle (Kreb's Cycle)?
Second step of cellular respiration in the mitochondrial matrix where carbon dioxide is released, producing 3 NADH, 1 FADH2, and 1 ATP.
174
What is oxidative phosphorylation?
Final step of cellular respiration marked by the production of ATP by the transfer of electrons down the electron transport chain.
175
What is ATP synthase?
A membrane-embedded protein complex that regenerates ATP from ADP with energy from protons diffusing through it.
176
What is the electron transport chain?
A series of four large, multi-protein complexes embedded in the inner mitochondrial membrane that accepts electrons from donor compounds.
177
What is chemiosmosis?
The movement of hydrogen ions down their electrochemical gradient across a membrane through ATP synthase to generate ATP.
178
What is the glycolysis equation?
Glucose + 2ATP + 2NAD + 4ADP → 2Pyruvate + 4ATP + 2NADH (2 Net ATP)
179
What is the citric acid cycle equation?
Pyruvate + CoA → Acetyl CoA + 3NAD + FAD + ADP + 3CO2 + 3NADH + 1 FADH2 + 1ATP → X2 because of the two pyruvate molecules (2 Net ATP)
180
What is the oxidative phosphorylation equation?
NADH + FADH2 + O2 + ADP → NAD+ + FAD + H2O + 28-34 ATP
181
What is the equation for photosynthesis?
6CO2 + 6H2O + sun light --> C6H12O6 + 6O2
182
What is the equation for cellular respiration?
C6H12O6 + 6O2 --> 6CO2 + 6H2O + ATP
183
What is a heterotroph?
An organism that cannot make its own food so it consumes other organisms.
184
What is an autotroph?
An organism capable of producing its own food.
185
What is a photoautotroph?
An organism capable of synthesizing its own food molecules (storing energy), using the energy of light.
186
Where does photosynthesis predominantly occur?
Leaves.
187
What is mesophyll?
The middle layer of cells in a leaf.
188
What is a stoma?
The opening that regulates gas exchange and water regulation between leaves and the environment.
189
What is a chloroplast?
The organelle where photosynthesis takes place and the site for carbon fixation in plants.
190
What are thylakoids?
A disc-shaped membranous structure inside a chloroplast where the light-dependent reactions of photosynthesis take place using chlorophyll embedded in the membranes.
191
What is chlorophyll?
The green pigment that captures the light energy that drives the reactions of photosynthesis.
192
What is chlorophyll A?
The form of chlorophyll that absorbs violet-blue and red light.
193
What is chlorophyll B?
The form of chlorophyll that absorbs blue and red-orange light.
194
What is a granum?
A stack of thylakoids located inside a chloroplast.
195
What is stroma?
The fluid-filled space surrounding the granum inside a chloroplast where the Calvin cycle reactions of photosynthesis take place.
196
What is the Calvin cycle?
Reactions of photosynthesis in which energy from ATP and NADPH is used to build high-energy compounds such as sugars.
197
What are light-dependent reactions and their purpose?
Convert light energy into chemical energy via photosystems.
198
What happens in Photosystem II?
Light excites chlorophyll, which will release an electron. To replace the electron, a molecule of water is broken. Oxygen and H+ are released into the thylakoid.
199
How does photosynthesis occur in prokaryotes?
Because prokaryotes lack membrane-bound organelles, photosynthesis happens within the plasma membrane, specifically in specialized inholdings containing photosynthetic pigments that act like thylakoids in plant chloroplasts.
200
What do plants do during the day?
Photosynthesis.
201
What do plants do at night?
Cellular respiration.
202
Which of the following is not a function of lipids?
- Insulates against cold
- cushions against physical damage
- catalyzes enzymatic reactions
- a source of energy
Catalyzes enzymatic reactions.
203
Which of the following are examples of carbohydrates?
Chitin
Hormones
Triglycerides
glycogen
cellulose
starch
Chitin, glycogen, cellulose, starch.
204
What is the problem in the hypothesis example?
I need to go to class but my car will not start when I turn the key.
205
What is the hypothesis in the example?
I think the car will not turn on because it is out of gas.
206
What is the prediction in the example?
If I add gas to the gas tank, the car will start.
207
What is the experiment in the example?
My friend takes me to the gas station and we buy gas, then fill the gas tank of my car.
208
What is the result in the example?
The car still did not start after I filled the tank.
209
What is the conclusion in the example?
An empty tank is not why my car would not start.
210
What are the tails of the phospholipids of the plasma membrane composed of?
Fatty acid groups; hydrophobic.
211
Which of the following is an example of an endergonic reaction?
- Glucose metabolism via glycolysis
- a hen incubating an egg that develops into a chick
- wood burning in a fireplace
- rolling a ball down a hill
A hen incubating an egg that develops into a chick.
212
Which of the following is not a product of glucose catabolism?
- water
- ATP
- oxygen
- carbon dioxide
Oxygen.
213
What are the primary functions of proteins?
- catalyze chemical reactions
- store biological information
- store energy
- form structural components of cells
Catalyze chemical reactions, form structural components of cells.
214
What is the basic unit of a molecule?
Atom.
215
What is the main substrate cells use for glycolysis?
Glucose.
216
Does aerobic respiration require the presence of oxygen?
yes
217
Which type of chemical bond stores potential energy for cells to use?
Covalent.
218
Which of the following are true?
- bacteria do not have membrane-bound organelles and are therefore prokaryotes
- eukaryotes do contain membrane-bound organelles
- plants are both prokaryotes and eukaryotes
- eukaryotes do not contain membrane-bound organelles
- eukaryotes include plants and animals
1. Bacteria do not have membrane-bound organelles and are therefore prokaryotes. 2. Eukaryotes do contain membrane-bound organelles. 5. Eukaryotes include plants and animals.
219
The cell membrane is composed of all of the following except:
- lipids
- nucleic acids
- proteins
- carbohydrates
Nucleic acids.
220
Where is the location of carbon fixation in plants?
Chloroplasts.
221
Which of the following are true about enzymes?
- are proteins that catalyze a chemical reaction
- are lipids that catalyze a chemical reaction
- decrease the activation energy of a reaction
- increase the activation energy of a reaction
1. Are proteins that catalyze a chemical reaction. 3. Decrease the activation energy of a reaction.
222
Oxidative phosphorylation occurs as part of ____ respiration?
Aerobic.
223
Water moves via osmosis ____
- throughout the cytoplasm
- from an area with a high concentration of other solutes to a lower one
- from an area with a low concentration of solutes to an area with a higher one
- from an area with a low concentration of water to one of a higher concentration
From an area with a low concentration of solutes to an area with a higher one.
224
Which of the following are part of the endomembrane system?
- endoplasmic reticulum
- nucleus
- lysosomes
- mitochondria
1. Endoplasmic reticulum. 2. Nucleus.
225
What is a process whereby molecules move from a region of low concentration to a region of a higher one?
- diffusion
- evaporation
- active transport
- passive transport
Active transport.
