Midterm study guide Flashcards
1
Q
study of life
A
biology
2
Q
pseudoscience
A
claims, arguments, or method that are presented as science but do not follow scientific principles
3
Q
most/least inclusive level of matter
A
biosphere/atoms
4
Q
population
A
group of interbreeding individuals of the same species living in a given area
5
Q
Community
A
Consists of all populations of all species in a given area
6
Q
Ecosystem
A
A community interacting with its physical and chemical environment through the transfer of energy and materials
7
Q
producers
A
make their own food using energy and nonbiological raw materials from the environment
8
Q
consumers
A
obtain energy and nutrients from organisms or their remains
9
Q
What is homeostasis?
A
Process in which cells and multi-celled organisms keeps their internal conditions within tolerable ranges by sensing and responding appropriately to change
10
Q
How does energy move within an ecosystem?
A
Energy moves from producers through to consumer to predators. Also - from environment, through organisms, and to environment.
11
Q
Is heat a usable energy source?
A
no
12
Q
How do nutrients move within an ecosystem?
A
Producer makes food, consumers eat organisms, decomposers feed on remains, nutrients release from decomposing consumers and return to environment back to the producers
13
Q
What is the purpose of DNA?
A
To guide ongoing cellular activities that sustain life.
-Growth, reproduction, development
14
Q
characteristics of bacteria and archaea
A
dna not in nucleus, single celled
15
Q
characteristics of eukarya
A
dna within nucleus, single or multi celled
16
Q
components found in both proks and euks
A
plasma membrane, cytoplasm, ribosomes, dna
17
Q
four main groups of euks
A
protists, plants, animals, fungi
18
Q
the linnaean system
A
created by carl linnaeus, gives every species a unique two part scientific name
19
Q
how are species classified
A
taxon/taxonomy
20
Q
what techniques do biologists use to determine the species of living things?
A
compare traits, compare dna
21
Q
components of the scientific name
A
genus and specific epithet
22
Q
biological species concept
A
a species as one or more groups of individuals that potentially can interbreed, produce fertile offspring, and do not interbreed with other groups
23
Q
hypothesis
A
testable explanation for a natural phenomenon
24
Q
scientific theory
A
A hypothesis that stands after many years of systematic testing, is consistent with existing evidence, and is useful for making predictions about a wide range of phenomena
25
What is a control group?
Identical to the experimental group except for one variable: the characteristic or treatment being tested
26
What is an experimental group?
A set of individuals that have a certain characteristic or receive a certain treatment
27
What are variables?
Experimental factor that varies: a characteristic that differs among individuals or an event that differs over time
28
What is sampling error and how do scientists avoid this when developing an experiment?
A difference between results obtained from a suspect, and results from the whole.
-use a large subset/increase sample size
29
What is critical thinking?
the deliberate process of judging the quality of information before accepting it
30
Why should a scientist design experiments that will yield quantitative results?
To avoid bias
31
How do scientists avoid bias?
Blinding, systematic random sampling, quality control, control group
32
What is an element?
Pure substances consisting only of atoms with the same number of protons in their nucleus
33
What is an atom?
Smallest unit of matter
34
What are the components of an atom?
nucleus, protons, neutrons, electrons
35
atomic number represents
number of protons in an atom's nucleus
36
atomic mass represents
total number of neutrons and protons in the nucleus of an isotope
37
subatomic particles location and properties
protons: positive in nucleus, neutrons: uncharged in nucleus, electrons: negative move around nucleus
38
what is the shell model
conceptual diagram of how electrons populate an atom
39
what are vacancies
when an atom's outermost shell has room for another electron
40
How many electrons can be held within each shell of an atom?
First: 2 electrons
Second: 8 electrons
Third: 8 electrons
41
How does the Octet Rule help to determine bonding?
states that electron transfer or electron sharing proceeds until an atom has acquired an octet of electrons
42
Why are noble gases stable?
Full valence electron shells
43
How can we calculate the atomic mass (mass number) of a particular atom?
Total number of neutrons and protons in the nucleus of an isotope
44
How can we calculate the number of protons in an atom? neutrons?
protons: atomic number
neutrons: mass number - atomic number
45
What does it mean when an atom is neutral? What does it mean when an atom is positively or negatively charged?
Neutral: An atom with exactly the same number of electrons and protons
Positive: More protons than electrons
Negative: More electrons than protons
46
isotopes
atoms of the same element that have different numbers of neutrons and same number of protons
47
ions
Atoms or molecules that carry a net charge
48
How does an atom become an ion?
By gaining or losing electrons
49
What type of bonding occurs from oppositely charged atoms
Ionic bond
50
What type of bonding occurs when the atoms share electrons?
Covalent bond
51
Why would an atom give, receive or share electrons?
To achieve stability
52
What makes H2O a polar molecule?
it has two polar covalent bonds. Oxygen atom carries a slight negative charge and each of the hydrogen atoms carries slight positive charge.
53
What are the major components of a solution?
solvent and solute
54
What is the pH of a solution?
a measure of its hydrogen ion concentration
55
What would cause the pH of a solution to become more acidic or basic?
more basic: fewer H+ ions than OH- ions
more acidic: more H+ ions than OH- ions
56
How does the H+ ion concentration affect the pH of a solution?
higher the H+, lower the pH
57
What are the pH ranges for an acidic, basic, or neutral solution?
Neutral: pH7
Acidic: below 7
Basic: above 7
58
What are the purposes of hydrolysis and dehydration reactions?
Dehydration: to build molecules up
Hydrolysis: to break molecules down
59
structure of carbohydrates
carbon, hydrogen, and oxygen in a ratio of 1:2:1
60
function of carbohydrates
Used for fuel, as structural materials, and for storing energy
61
monosaccharide examples
glucose, galactose, fructose (simple sugars)
62
polysaccharide examples
starch and glycogen
63
characteristics of glycogen
storage form of glucose, ready form of energy. sugars are formed in this form
64
characteristics of cellulose
most abundant organic molecule on Earth, forms tough fibers, insoluble in water, not easily broken down
65
characteristics of starch
does not dissolve easily in water - however, easier than others
66
What are the general properties of fatty acids?
small organic molecule, consists of a long hydrocarbon tail with a carboxyl group head. attract oily dirt, dissolve dirt in water
67
structure of saturated fats
Lack double bonds between individual carbon atoms, tend to be solid and from animal sources. Triglyceride with 3 saturated fatty acid tails that are flexible and can pack together tightly.
68
structure of unsaturated fats
At least one double bond in the fatty acid chain, tend to be liquid and from plant sources. Triglyceride with one or more fatty acid tails that are kinky and cannot pack together tightly.
69
saturated fats food sources
meats, dairy, butter/lard
70
unsaturated fats food sources
oils, nuts, fish
71
structure of a triglyceride
3 fatty acids bonded to the same glycerol
72
function of a triglyceride
long term storage of energy/source of energy
73
structure of a phospholipid
two long hydrocarbon tails and a head with phosphate group
74
function of a phospholipid
make up cell membranes
75
What are the monomers of proteins
amino acids
76
polymers of proteins
polypeptides
77
components of an amino acid
carbon group, nitrogen group, single hydrogen atom, r group
78
what determines amino acid type
r group
79
what bonds are found between the amino acids within a polypeptide
peptide bonds
80
function of enzymes
speed up metabolism or chemical reactions in our bodies. build up or break down
81
monomers of nucleic acids
nucleotides
82
function of nucleic acids
store and transmit genetic information
83
components of cell theory
all living things are composed of cells, cells are the basic units of structure and function in living things, new cells are produced from existing cells
84
What kind of aspects will limit the size of the cell?
Rates of protein synthesis, folding rates of it slowest proteins and the rates of its protein diffusion
85
How is the surface area and volume of the cell related?
Volume increases more rapidly than the surface area so the amount of surface area available to pass materials to a unit volume of the cell steadily decreases
86
How did the microscope contribute to the development of the cell theory
allowed us to see different aspects of cell structure
87
What components are found in all cell types?
plasma membrane, cytoplasm, DNA, ribosomes
88
What are some cellular structures found in eukaryotic cells but not bacteria?
Endoplasmic reticulum, microtubules, and the Golgi apparatus
89
What are some cellular structures found in plant cells but not animals cells?
Chloroplasts, cell wall, central vacuole
90
describe the overall structure of the lipid bilayer
two layers of phospholipids, with a hydrophobic interior and a hydrophilic exterior
91
Properties of phospholipid?
They anchor proteins within the cell membranes, they are the major constituent of the cell membrane.
92
Which components of phospholipids are hydrophilic/hydrophobic
Interior is hydrophobic, exterior is hydrophilic
93
What is the fluid mosaic model?
describes the structure of the plasma membrane - phospholipids, cholesterol, proteins, carbohydrates
94
Function of the nucleus
Directs all the cells activities; contains the cells DNA
95
Function of cytosol
contains many metabolic pathways; protein synthesis; the cytoskeleton
96
Function of cytoplasm
responsible for cell shape, material transport like genetic material and products for cellular respiration, and storage
97
function of cell membrane (plasma membrane)
regulates what goes in and out of the cell
98
function of mitochondria
produces ATP
99
function of chloroplast
photosynthesis
100
function of ribosomes
make proteins
101
function of flagella
movement
102
function of cilia
move liquid past the surface of the cell
103
function of rough endoplasmic reticulum
makes and modifies proteins
104
function of smooth endoplasmic reticulum
makes phospholipids, stores calcium, and has additional functions in some cells
105
function of golgi body
modifying, sorting and packaging of proteins for secretion
106
Function of transport vesicles
help move materials, such as proteins and other molecules, from one part of a cell to another
107
what does it mean to be a "membrane bound" organelle?
completely surrounded by a plasma membrane, or even a double membrane
108
What cell types would have a flagellum?
Bacteria, archaea, and eukaryota
109
How do cilia and flagella allow for movement in different cells?
Flagella and cilia help propel/ move a cell through liquid
110
What organelles are involved in the endomembrane systems?
Nuclear envelope, lysosomes, vesicles, endoplasmic reticulum, Golgi apparatus, and plasma membrane
111
What is a biofilm? Give an example
refers to a living microbial ecosystem that grows and adheres to a solid surface.
(Plaque that grows on teeth)
112
What are reactants and products within a reaction?
reactants are the molecules that are needed to create a product and the product is the end result of the reaction
113
What is activation energy
minimum energy required for a reaction to occur.
114
how do cells store a retrieve energy from organic molecules?
cells store energy by running reactions that assemble organic molecules
115
What is the first law of thermodynamics? Give an example
energy cannot be created or destroyed. ex: human metabolism with conversion of food into energy
116
What is the second law of thermodynamics? Give an example
energy tends to disperse spontaneously. ex: sweating, dispersing of energy to cool down the human body
117
What is the definition of work?
transfer of energy
118
What is ATP?
adenosine triphosphate
-an energy-carrying cell found in all life
119
potential energy
energy that is stored
120
kinetic energy
energy in motion
121
function of enzymes
speed up chemical reactions
122
What is enzyme specificity?
when the enzyme works best in a particular range of conditions
123
What is the active site?
the region on the enzyme where the substrate binds
124
Describe some of the effects that can cause enzymes to not work properly
temperature, pH, and salt concentration
125
What is the purpose of enzymes in a metabolic pathway?
Make reactions happen faster - by building together or breaking apart
126
passive transpot
doesn't require energy
127
active transport
requires energy
128
Describe the movement of a solute via diffusion
the spontaneous spreading of molecules or atoms through a fluid or gas
129
facilitated diffusion
movement of molecules can occur both in direction and opposite of the concentration gradient
130
simple diffusion
movement particles occurs along the direction of the concentration gradient
131
What is osmosis?
diffusion of water through a selectively permeable membrane from area of high water potential (low solute concentration) to an area of low water potential (high solute concentration)
132
What determines the movement of water across the cell membrane?
depends on the relative solute of the concentration of the two fluids
133
When a cell interacts with a hypertonic solution what kind of movement occurs across the membrane
the water diffuses in the cell, causing them to shrivel up
134
When a cell interacts with a hypotonic solution what kind of movement occurs across the membrane
the water diffuses in the cell, causing them to swell
135
What does it mean when solutions are isotonic? Describe the water/solute movement.
Isotonic: the fluid has the same overall solute concentration
-when no concentration gradient so no large movement of water in or out
