bio final Flashcards
(233 cards)
1
Q
definition of science
A
the study of the structure and behavior of the physical and natural world through the scientific method
2
Q
a suggested explanation for an event is called
A
a hypothesis
3
Q
a tested and confirmed explanation for observed phenomena is called
A
a theory
4
Q
The scientific method
A
observation, question, hypothesis, prediction, experiment, result
5
Q
inductive reasoning
A
drawing general conclusions from specific observations or data
6
Q
deductive reasoning
A
reasoning that starts with a general premise or hypothesis and uses it to draw specific conclusions
7
Q
independent variable
A
The variable you change
8
Q
controlled variables
A
variables that are set for the experiment to allow for a repeatable, correct experiment
9
Q
dependent variable
A
Depends on the IV. Subject to change based on the IV. Don’t touch this variable
10
Q
Characteristics of life
A
Cellular organization, reproduction, heredity, metabolism, homeostasis, response to stimuli, growth and development, adaptation through evolution
11
Q
Describe homeostasis
A
The human body maintains internal balance and when something is out of balance the body finds way to return to balance
12
Q
what are set points (homeostasis)
A
a specific value or range of a physiological variable that the body aims to maintain
13
Q
negative feedback loop (homeostasis)
A
A loop that acts to oppose the stimulus that triggers them and return the body to homeostasis
14
Q
positive feedback loop (homeostasis)
A
this loop amplifies an initial change leading to further deviation from a set point
15
Q
Order the levels of the biosphere from largest to smallest
A
Biosphere –> biome –> ecosystem –> community –> population –> organism
16
Q
biodiversity
A
differences of biological species or organisms in a certain area
17
Q
what is a control group?
A
a group where the tested variable is not applied to test the base answer of the experiment in order to compare data from the tested group
18
Q
define homeostasis
A
same state
19
Q
example of a system that needs to maintain homeostasis?
A
humans with body temperature
20
Q
Define exothermic
A
a reaction or process accompanied by the release of heat
21
Q
Define endothermic
A
a reaction or process accompanied by the absorption of heat
22
Q
what is the pH scale (what does it show)?
A
it measures how acidic or basic a liquid is.
23
Q
List one acid, one normal, and one base (with their numbers)
A
Stomach acid (1 - acidic) Water (7 - normal) Drain cleaner (14 - basic)
24
Q
Describe covalent bonds
A
a chemical bond that involves the sharing of electrons
25
describe ionic bonds
a chemical bond formed by the complete transfer of valence electrons between atoms
26
describe hydrogen bonds
a weak bond between a hydrogen atom covalently bonded to a highly electromotive atom
27
what is the element that makes up all organic matter?
carbon
28
why is the atom of Carbon able to bond so effective?
it has 4 valence electrons
29
Carbon can make large structures, name the 3 types of structures
Straight, branched, ring
30
Define a monomer
a molecule that can be bonded to other identical molecules
31
What are the four major types of carbon based macro molecules?
lipids, proteins, carbohydrates, nucleic acids
32
what are enzymes?
A substance produced by a living organism that brings out a specific reaction
33
why are enzymes important?
they accelerate chemical reactions within living organisms.
34
what happens to an enzyme when there is a pH and/or temperature change?
Denatures it, causing it to not be as potent
35
Enzyme found in the human body
Lactase
36
why are enzymes important to the survival of an organism?
they speed up biochemical reactions that are vital for survival
37
What are peptide bonds?
bonds that connect amino acids in proteins
38
how do carbohydrate monomers bond together to form polysaccharides?
by dehydration synthesis (removing water)
39
describe polarity of a molecule
uneven sharing of electrons causing partial charges
40
explain cohesion
Attraction between molecules of the same kind
41
explain adhesion
attraction between different types of molecules
42
explain high specific heat (property of water)
water resists temperature change (helps keep earth's climate stable)
43
explain density of solid H2O
Ice is less dense than liquid because water molecules spread out when frozen
44
Explain universal solvent
a substance that can dissolve a wide range of other substances, commonly associated with water
45
if we didn't have hydrogen bonds what would happen?
the properties of water would no longer exist causing the death of species and changes in the environment
46
what is the basic unit of life?
The cell
47
What are the 3 parts of cell theory?
All living things are made of cells; cells are the basic unit of life; all cells come from other cells
48
where does energy production happen in the cell?
Mitochondria
49
What organelle makes protiens?
Ribosome
50
what is the function of the cell membrane?
controls what goes in and out of the cell
51
what structure gives plant cells shape?
Cell wall
52
what do chloroplasts do?
perform photosynthesis
53
What is the main function of carbohydrates?
provide energy
54
what do proteins do?
build and repair cells
55
what is DNA made of?
nucleotides
56
What is DNA
genetic material
57
what is a gene
a section of DNA that codes for a trait
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what is a chromosome?
coiled DNA found in the nucleus
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Dominant (gene)
A trait that shows even if only one allele is present
60
recessive (gene)
a trait that only shows if 2 alleles are present
61
what is a genotype?
The genetic makeup
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what is a phenotype?
the physical trait
63
what is mitosis
cell division that makes identical cells
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what is meiosis
cell division that makes sex cells
65
what is photosynthesis?
plants making food using sunlight
66
what is the formula for photosynthesis?
CO₂ + H₂O + sunlight → glucose + O₂.
67
What is cellular respiration?
breaking down food for energy
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what is the formula for cellular respiration?
Glucose + O₂ → CO₂ + H₂O + energy.
69
what is an ecosystem
all living and nonliving things in an area
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what is a producer?
an organism that makes it's own food
71
what is a consumer?
an organism that eats other organisms
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what is a decomposer?
an organism that breaks down dead matter
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what is a food chain
a series of organisms showing who eats whom
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what system pumps blood?
circulatory sysytem
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what system controls body activities
nervous system
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why is polarity important in molecules?
it allows molecules like water to dissolve things and stick together
77
what part of the cell contain the DNA?
Nucleus
78
Lysosomes contain enzymes used for which process?
breaking down hazardous stuff in the body
79
where are ribosomes produced?
the nucleus
80
what organelle packages and distributes proteins?
the golgi-body
81
Which organelle acts as a storage container?
Vacuole
82
What do vacuole store?
water, nutrients, waste
83
What 3 organelles are found in plant cells but not in animal cells?
chloroplasts, cell walls, central vacuole
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What is passive transport?
transport that doesn't require energy
85
Name 3 types of passive transport
Diffusion, osmosis, and facilitated diffusion
86
What is diffusion
movement of molecules from high to low concentration
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what is osmosis?
diffusion of water across a membrane
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what is facilitated diffusion
movement of molecules through a protein channel
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what is active transport?
transport that requires ATP to happen
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how does active transport occur?
molecules move from low to high concentration using energy and transport proteins
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what are the functions of the cell membrane?
controls what enters and leaves the cell, protects the cell, provides cell structure, and helps communicate with other cells
92
what are the components of the cell membrane?
gate proteins, signal proteins, channel proteins, phospholipids, cholesterol, carbs
93
explain the cycle that ATP goes through
ATP releases energy by losing a phosphate to become ADP, then regains a phosphate to become ATP again
94
How is the cycle of ATP important for the cell to function?
it provides a constant supply of energy needed for all cell activities
95
Define hypotonic
water moves into the cell (lower solute concentration than the cell)
96
Define hypertonic
water moves out of the cell (higher solute concentration than the cell)
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define isotonic
water moves in and out equally
98
define photosynthesis
the process plants use to make food (glucose) using sunlight, CO2, and water
99
what enzyme is used in photosynthesis
ATP synthase
100
define the granum
a stack of thylakoids inside a chloroplast
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define the thylakoid
a single disk where the light reactions happen
102
define the stroma
fluid inside a chloroplast where the Calvin cycle occurs
103
describe what chlorophyll is
a green pigment in chloroplasts
104
what does chlorophyll do?
it absorbs sunlight to help plants make food during photosynthesis
105
what are stomata?
small openings on a leaf's surface
106
what do stomata do?
they allow CO2 to enter and O2 and water vapor to leave
107
describe how the light dependent reactions work
they use sunlight to split water, release oxygen, and make energy molecules (ATP and NADPH) for the Calvin cycle
108
explain how the H+ concentration is built up on the inside of the membrane
water is split, releasing H+ ions inside the thylakoids. Electron transport also drops H+ ions into the thylakoid space
109
explain what the H+ ions are used for once the concentration is built up
they flow through ATP synthase to make ATP from ADP and phosphate (chemiosmosis)
110
explain the Calvin cycle
a process in the stroma that uses ATP and NADPH to convert CO2 into glucose (dark reaction)
111
how can the Calvin cycle continue to produce glucose even though 6 carbons are leaving the cycle?
Other than regenerating RuBP, other reactions in the thylakoid produce extra carbon compounds that feed back into the cycle
112
the movement of water across a semipermeable membrane is called
osmosis
113
what is the term for the process by which large molecules or particles are taken into a cell
endocytosis
114
define equilibrium
when particles are evenly spread out and move equally in both directions
115
why is it important that the phospholipid bilayer has hydrophobic and hydrophilic parts?
Hydrophilic (polar) heads face water, and hydrophobic (nonpolar) tails face inward, creating a stable barrier
116
what is the basic structural unit of DNA
Nucleotide
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what are the parts of a nucleotide?
phosphate, sugar, nitrogenous base
118
what is the shape of DNA?
double helix
119
for the following nitrogenous base, pair it correctly with the complementary DNA nucleotide: A
T/U
120
for the following nitrogenous base, pair it correctly with the complementary DNA nucleotide: C
G
121
for the following nitrogenous base, pair it correctly with the complementary DNA nucleotide: T
A
122
for the following nitrogenous base, pair it correctly with the complementary DNA nucleotide: G
C
123
what is the primary function of DNA replication?
to make an exact copy of DNA before a cell divides
124
in which phase of the cell cycle does DNA replication occur
S (synthesis) phase of interphase
125
during DNA replication, which enzyme is responsible for unwinding the double helix?
Helicase
126
during DNA replication, which enzyme creates the replicated stands?
Polymerase
127
Okazaki fragments are associated with DNA replication. Explain what they are?
Short DNA pieces made on the lagging strand during DNA replication
128
How are okazaki fragments used?
DNA ligase joins them together to form a complete strand
129
describe the purpose of transcription
to copy a gene from DNA into mRNA
130
which enzyme is responsible for transcription?
RNA polymerase
131
in which organelle does transcription occur in cells?
Nucleus (where the DNA is stored)
132
what's the purpose of translation?
To use mRNA to build a protein
133
in which organelle does translation occur in?
the ribosomes of a cell
134
what is a codon?
A 3 letter sequence of mRNA that codes for one amino acid
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which molecule carries amino acids to the ribosomes during translation?
tRNA (transfer RNA)
136
what is an anticodon?
a 3 letter sequence on tRNA that pairs with a codon on mRNA
137
what is the function of ribosomes in translation?
ribosomes read the mRNA and link amino acids together to make a protein
138
what is the function of mRNA
mRNA carries the genetic code from DNA to the ribosome
139
what is the function of rRNA?
it makes up the ribosome and read the mRNA and build the protein
140
what do polysaccharides store?
energy
141
what are cell walls made of
cellulose
142
what makes up exoskeletons
chitin
143
what's an example of a monosaccharide?
glucose
144
what's an example of a disaccharide?
sucrose
145
what's an example of a polysaccharide?
starch
146
what are lipids used for?
insulation and long term energy storage
147
what's the difference between saturated and unsaturated fats?
saturated fats have no double bonds between carbon atoms - solid at room temp. Saturated fats have one or more double bonds - liquid at room temp
148
what does a steroid look like?
4 fused rings
149
what are the base pairs
adenine - thymine and guanine - cytosine
150
what is the backbone of DNA made out of?
Sugar phosphate
151
what are nucleic acids?
information storing molecules
152
Is DNA a nucleic acid?
Yes
153
is RNA a nucleic acid?
Yes
154
what does each nucleotide consist of?
A sugar (deoxyribose or ribose), A phosphate, a nitrogen base (adenine, thymine, guanine, cytosine, uracil (in RNA)
155
what are the functions of proteins?
support, transport, hormones, enzymes, defense, motion
156
what are proteins made up of?
amino acids joined by peptide bonds
157
How is the structure of the
cell related to function?
each organelle has a shape and structure that helps it do its job
158
Why are cells so small?
So they can move materials in and out quickly
159
What do all cells have?
Cytosol, plasma membrane, ribosomes, and DNA
160
What do prokaryotic cells NOT have?
a membrane bound nucleus (bacteria)
161
What DO eukaryotic cells have
membrane bound nucleus, various organelles, cytoplasm
162
where are ribosomes creates?
inside the nucleolus which is inside the nucleus
163
what are the squiggly lines inside the nucleus?
chromatin
164
what happens w/ ribosomes?
protein synthesis
165
structures in eukaryotic cells
centrioles, lysosomes, nucleolus, chromatin, ribosomes, rough ER, nucleus, Golgi body, vesicles, smooth ER, microtubules, cell membrane, mitochondria
166
what is the mitochondria
powerhouse of the cell, provides energy in form of ATP, responsible for cellular respiration
167
what are lysosomes?
"garbage disposal" because they break down substances
168
what are vacuoles
used for storage and transport
169
are plant cells vacuoles larger or smaller than animal cell
larger, they have one central large vacuole
170
what are centrosomes? (centrioles)
they move chromosomes during cell division, they also build the cytoskeleton
171
what are chloroplasts?
(plant cells only) the site of photosynthesis
172
what is the cell wall
(plant cells only) rigid structure made of cellulose
173
what are vesicles
helps transport materials out of the cell
174
what is ER
endoplasmic reticulum transports proteins
175
what is the golgi apparatus
it packages and exports things
176
what is the cytoskeleton?
network of fibers that give support and structure to the cell
177
what is the fluid part of cytoplasm?
cytosol
178
what happens inside the nucleolus?
the nucleolus makes ribosomes which move to the rough ER where they participate in protein synthesis
179
what is inside the nucleus?
DNA, nucleolus, cytoplasm
180
what happens in the rough ER
proteins are made and processed
181
what happens in the smooth ER
it makes lipids and steroid hormones and breaks down toxins
182
what are ribosomes used for?
they read mRNA and link amino acids together to build proteins
183
what does the golgi body do?
it packages and delivers enzymes + hormones within the cell
184
what do lysosomes do?
they break down waste and old cell parts
185
what do peroxisomes do?
they break down acids and detox harmful chemicals
186
what do vesicles do?
they transport materials around the cell
187
what do vacuoles do?
they store water, nutrients, and waste
188
what is the cytoskeleton made up of?
microtubules and microfilaments
189
what do centrosome(s) do?
they organize microtubules and help during cell division
190
what are the stages of cellular respiration?
glycolysis, Kreb's cycle, ETC (electron transport chain)
191
what happens during glycolysis?
Glucose is broken down into 2 pyruvate molecules.
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what happens during the Kreb's cycle?
Pyruvate is broken down to release energy.
193
What happens in the ETC?
Energy carriers (NADH & FADH₂) drop off electrons to make lots of ATP.
194
why do we need oxygen?
Oxygen is the final electron acceptor in the electron transport chain.
195
where does cellular respiration occur within the cell?
In the cytoplasm and mitochondria.
196
what is the waste product of cellular respiration?
Carbon dioxide (CO₂) and water (H₂O).
197
why do you need to breathe?
to bring in oxygen which Is needed for cellular respiration to make ATP
198
What are the different types of evidence for evolution
Fossils, homologous structures, vestigial organs, DNA, embryos, direct observation
199
what does fossil evidence show?
similarities between past animals and living animals / transitional species
200
what are homologous structures
same bones, different functions
201
what are vestigial structures?
organs or parts that seem to have no function
202
how can DNA be used to prove evolution?
when comparing DNA, more similarities are found in species that are more closely related
203
how can you use embryos to prove evolution?
different species embryos develop in almost identical ways
204
example of direct observation of evolution?
bacteria become resistant to antibiotics
205
what does mRNA do?
carries DNA instructions to the ribosomes
206
what does rRNA do?
subunits of ribosomes
207
what does tRNA do?
carries amino acids to ribosome
208
the process of turning DNA into RNA is called
transcription
209
the process of turning RNA into protein is called
translation
210
what is a codon?
a 3 letter mRNA sequence that codes for an amino acid
211
what is an anti codon?
a 3 letter tRNA sequences that matches the codon
212
what are the four nitrogen bases?
Purines: Adenosine + Guanine // Pyrimidines: Thymine + Cytosine
213
Nucleotides contain...
a sugar (deoxyribose), phosphate, and a nitrogen base
214
what direction does DNA polymerase travel?
3 prime to 5 prime
215
what is the job of DNA polymerase?
it ads nucleotides and binds the sugars and phosphates
216
what is the job of DNA Helicase?
to unzip the DNA
217
what is the purpose of the leading strand?
it's made continuously (5' to 3')
218
what is the purpose of the lagging strand?
it's made in short pieces because it runs in the opposite direction
219
what is the purpose of the replication fork?
it's the area where DNA is unwound and copied
220
what is the purpose of ligase?
Joins DNA fragments together (seals gaps between Okazaki fragments on the lagging strand)
221
what are telomeres?
the caps at the end of each strand of DNA that protect our chromosomes (get shorter each time a cell copies itself)
222
what happens when telomeres get too short?
they can't do their job causing our cells to age and stop functioning properly
223
what are the stages of the cell cycle
Interphase, mitosis, cytokinesis
224
what happens in Interphase?
the cells grows and copies its DNA
225
what happens in mitosis?
the nucleus divides
226
what happens in cytokinesis?
the cell splits into two
227
what are the steps of cell division that happen in mitosis?
Interphase (before mitosis) Prophase, metaphase, anaphase, telophase (IPMAT)
228
what happens in Interphase?
G1, S, G2 phases
229
what happens in prophase?
Chromosomes visible, spindle forms as centrioles move
230
What happens in metaphase?
Chromosomes line up along equator
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what happens during anaphase?
chromatids separate
232
what happens during telophase?
nuclear membrane forms, cytokinesis begins
233
what happens if any of the checks fail during the cell cycle?
Apoptosis (programmed death)
