Bio 101 AOL Material Flashcards
(108 cards)
1
Q
The five biological themes are:
A
Evolution
Cooperation
Homeostasis
The flow of energy
Structure determines function
2
Q
What are the domains that the six kingdoms are grouped in?
A
Eukarya, Archaea, Bacteria
3
Q
Which is true of evolution?
A
It is the genetic change over time
Can occur within a single species or can lead to formation of many new species
Natural Selection
4
Q
What is the next level of organization directly after tissues?
A
Organs
5
Q
The flow of energy is responsible for shaping the ecosystem
A
True
6
Q
The scientific method is an iterative (ongoing) process
A
True
7
Q
What is the smallest unit of life?
A
A cell
8
Q
Geckos have the ability to walk up the walls due to weak temporary molecular attractions known as
A
Van der Waals forces
9
Q
What are atoms when they gain and lose electrons?
A
Cations and anions
10
Q
What is the trend of electronegativity on the period table?
A
Increasing electronegatively from left to right
11
Q
What is the name of a process where a water molecule spontaneously splits into a positively charged hydrogen ion (H+) and a negatively charged hydroxide ion (OH-)?
A
Ionization
12
Q
What are the unique properties of water?
A
Heat storage
Ice formation
High heat vaporization
Cohesion and adhesion
High polarity
13
Q
What are amino acids an example of?
A
Monomers
14
Q
Lipids (fats) are used for long-term storage
A
True
15
Q
How does the complementary structure of DNA help its function?
A
Each strand of DNA mirror each other so the DNA contain two copies of information that can be passed to the next generation
16
Q
What is the monomer of proteins?
A
Amino acids
17
Q
Enzymes are examples of what kind of macromolecules?
A
Proteins
18
Q
Which of these are true regarding DNA and RNA?
A
RNA is single-stranded and contains a ribose-sugar phosphate backbone; DNA is double stranded and contains a deoxyribose-sugar phosphate backbone.
19
Q
All of the following are basic features of a cell except
A
Mitochondria
20
Q
What properties of molecules influence how well they are able to cross the lipid portion of the membrane?
A
Size
Polarity
Charge
21
Q
The nucleus is not the only organelle which contains DNA. Which other organelle(s) contain(s) DNA?
A
Both mitochondria and chloroplasts
22
Q
The left side of the beaker in the diagram is ______ to the right side of the beaker
A
Hypertonic
23
Q
Osmosis is the net (overall) movement of water molecules across a membrane from an area of high concentration to an area of low concentration.
A
True
24
Q
What is the difference between active and passive transport?
A
Active transport requires an input of energy, passive transport does not
25
What are life's most abundant atoms?
Carbon, Nitrogen ,Hydrogen, Oxygen
26
Hierarchy of Life
Atoms
Molecule
Macromolecule
Organelle
Cell
Tissue
Organ
Organ System
Organism
27
Osmosis
When water moves from high water concentration to low water concentration, and crosses a membrane
28
Scientific Method
Make observation
Think of a question
Formulate hypothesis
Develop testable prediction
Gather data to test predictions
Develop general theories
29
Six kingdoms of diversity of life
Archea
Bacteria
Protista
Fungi
Plantae
Animalia
30
Basic structure of atoms: Carbon atom
The innermost shell can hold up to 2 electrons
The other shells can hold up to 8 electrons
31
Giving up electron or accepting electrons
= formation of iconic bonds
32
Sharing electrons
= formation of covalent bonds
33
Ions are atoms or
molecules that have full positive or negative
charges
True
34
Neutral Atom
Loses electrons = cation
Gains electrons = anion
True
35
Bond Strength:
Covalent bonds > Ionic Bonds > Hydrogen bonds
True
36
Ionic Bonds
involve the attraction of opposite electrical charges
37
Covalent bonds
form when atoms share electrons with each other
38
Electronegativity
a measure of how much an atom attracts
electrons.
39
Nonpolar covalent bond
equal sharing of electrons between 2 atoms
40
Polar covalent bond
unequal sharing of electrons between 2 atoms
41
Examples of polar molecules
Water (H2O)
Glucose sugar (C6H12O6)
42
Is water a polar molecule?
Yes, with 2 polar covalent bonds
43
Hydrogen Bonds
weak electrical attractions between the partially positive end of one polar molecule and the partially negative end of another
44
Hydrogen is the partially positive
end of each polar molecule
True
45
Hydrogen bonds are weaker and
more flexible than covalent bonds
True
46
van der Waals’ forces
Electrostatic interactions between atoms that have a TEMPORARY PARTIAL charge
(very weak)
47
Water H2O
-The chemistry of life is the water chemistry
-Water (H2O) is a polar covalent molecule
-Water can form hydrogen bonds
48
Cohesion and adhesion
Cohesion – when one water molecules is attracted to another
water molecule
Adhesion – When polar molecules other than water stick to water molecule
49
In a liquid state, water molecules tend to form the maximum number of hydrogen bonds.
True
50
Hydrogen bonding = water molecule & polar molecule
True
51
Hydrophilic molecules
molecules are
attracted to water, and water molecules cluster around hydrophilic molecules using
hydrogen bonds
Ex: polar molecules, molecules w ionic bonds
52
Hydrophobic molecules
Molecules are
repelled by water and do not dissolve in it
These molecules are
nonpolar and do not form hydrogen bonds
Ex: lipids (oils, fats)
53
pH stands for
“potential hydrogen”
The amount of hydrogen ions (H+) from water in a liquid solution can be measure as pH
54
Acidic solutions
have pH values
below 7
contain more
hydrogen ion (H+) than hydroxide
ions (OH- )
55
Basic solutions
have pH values above
7
Basic solutions contain more hydroxide ion (OH- ) than hydrogen
ions (H+)
56
The pH of most living cells
and their environments is
close to 7
True
57
Proteins involved in metabolism are sensitive to any pH changes and can
denature (unfold)
True
58
Buffers
(Organisms use buffers to minimize pH disturbances)
A buffer is a chemical substance that takes up or releases hydrogen ions
* Buffers help to maintain homeostasis (stable internal conditions).
59
Four types of macromolecules:
*Proteins (Enzyme): enzymes, structural support, other roles
* Nucleic acids (DNA): genetic storage of information
* Carbohydrates (Starch): energy storage, structural support
* Lipids (Fats/Triaglycerol): energy storage, structural support, other roles
60
Polymers Are Built of Monomers
True
Macromolecules (polymers) <-monomers
61
Protein (polymer) macromolecule
are polymers of many
subunits called amino acids (monomer)
62
The functional group gives amino acids their
chemical identity.
* There are 20 different types of amino acids
R- Group
True
63
R groups differ
between amino acids, and that these
difference will influence the shape
and function of a protein
True
64
Amino Acids linked together by Peptide Bond
The covalent bond
linking two amino
acids together is
called a peptide
bond.
The assembled
polymer is a called
polypeptide
65
The order of amino acids affects
how the polypeptide chain fold
together.
* The way that a polypeptide folds
together determines the protein’s
function.
True
66
Primary structure
the sequence of amino
acids in the polypeptide
chain
67
Secondary structure:
the initial folding
of the polypeptide chain
Hydrogen bonds form between different parts of the polypeptide
chain
68
Tertiary Structure
the final 3-D shape of the polypeptide
69
Quaternary Structure
the spatial arrangement of
component polypeptides
in proteins composed of more than one
polypeptide chain
70
Monomer: Nucleotide
Polymer: Nucleic acid (DNA)
71
DNA Double Helix
The structure of DNA
deoxyribonucleic
acid) is a double
helix
Two strands of DNA are held together by hydrogen bonds
between bases on opposite strands
Adenine (A) pairs with thymine
(T)
* Cytosine (C) pairs with
Guanine (G)
72
Structure of DNA
The hydrogen bonds of the base pairs can
be broken to unzip the DNA so that
information can be copied.
* Each strand of DNA is mirror image so the
DNA contains two copies of the
information.
* Having two copies means that the
information can be accurately replicated
and passed the next generation
73
There are two types of nucleic acids.
-Deoxyribonucleic acid (DNA)
-Ribonucleic acid (RNA)
* uses uracil instead of thymine.
* usually composed just one strand
* has a ribose sugar instead of
deoxyribose sugar.
74
RNA is an important participant during
protein synthesis and DNA replication
True
75
Monomer: Monosaccharide
Polymer: Carbohydrate (starch)
used for energy or
sometimes act as structural molecules
76
Simple carbohydrates are made up of
one (monosaccharides) or two
(disaccharides) sugars (monomers)
* Complex carbohydrates are
polysaccharides (long polymers)
true
77
Lipids
fats and other
molecules that do not dissolve
in water (Insoluble)
-Lipids are nonpolar molecules.
* Lipids include fats,
phospholipids, and many other molecules
78
Fats have two types of subunits
-Fatty Acids
-Glycerol
78
If the maximum number of
hydrogens are attached, then the
fat is called saturated.
* If there are fewer than the
maximum attached, then the fat is
called unsaturated.
fewer hydrogens= unsaturated
79
what make up the
two layers of the cell
membrane
Phospholipids
80
Cholesterol
is embedded
within the membrane and provides flexibility
81
Hydrophilic (“water-loving) heads face the outside and inside of cell.
* Hydrophobic (“water-fearing’”) tails cluster within the core of the cell membrane.
True
82
Lipids also include:
Steroid hormones
* Testosterone, estrogen
* Rubber
* Waxes
* Pigments
* Ex. Chlorophyll in plants
* Makes leaves green and photosynthetic
83
The Cell Theory
-All organisms are composed of one or more cells.
-Cells are the smallest living things.
-Cells arise only by division of previously existing cells
84
All Cells have:
-Cell membrane (plasma membrane)
-Cytoplasm
-Genetic material (DNA)
-Ribosomes
85
Phospholipids
polar head
nonpolar tail
86
Prokaryotes vs. Eukaryotes
Eukaryotic cell
* Has a nucleus and other membrane-
bound organelles
* All other kingdoms (Animalia, Plantae,
Fungi, and Protista) have this cell type
Prokaryotic cell
* Lacks a nucleus and does not have an
extensive system membrane-bound
organelles.
* All bacteria and archaea have this cell
type
87
Cholesterol acts like a
“buffer” for membrane
fluidity
True
Temperature decrease = decreasing fluidity
88
Prokaryotes are the simplest cellular
organism
True
89
Organelle:
a structure that performs a
particular process
* Mitochondria, chloroplast, Golgi complex,
lysosomes, endoplasmic reticulum
90
The cytoplasm is semi-fluid and contains
a network of protein fibers that form a
scaffold called cytoskeleton
True
91
* The cells of plants, fungi, and many protists have a cell wall
external to the cell membrane.
* Cells of plants and protists contain chloroplasts.
* Plant cells contain a central vacuole.
* Plant cells also have a plasmodesmata (connective openings in the cell wall)
True
92
Endosymbiotic Theory:
These energy-harvesting organelles were derived from
ancient bacteria that were taken up by precursor
eukaryotic cells
93
Why does a cell need a membrane?
* To distinguish
itself from its
surroundings
* To be
selective
about what
gets in and
out
94
Selectively permeable
some substances are able to pass through the membrane, while other substances are not able to pass through
lipid bilayers
95
What properties of
molecules
influence how well
they are able to
cross through the
lipid portion of the
membrane?
hydrophobic
small uncharged polar molecules
large uncharged polar molecules
ions
96
Direct diffusion (passive) through the lipid bilayer
Energy NOT
required
97
Active transport (using carrier proteins)
Membrane folding: bulk passage of materials in and out of cells (active)
Energy required
98
Concentration gradient:
the concentration
difference across the membrane (C1 – C2)
99
Hydrophobic molecules can diffuse
freely through a lipid bilayer
True
100
The net (overall) movement of molecules from an area of higher concentration
to an area of lower concentration is called diffusion.
* Molecules diffuse down their concentration gradient.
* Equilibrium is reached when molecules are evenly dispersed within a
confined space.
* Diffusion is a passive process that requires no input of energy.
True
101
Osmosis does not require
an input of energy
True
102
the solution with the
higher solute concentration is said to
be hypertonic,
True
103
and the solution with
the lower solute concentration is
said to be hypotonic
True
104
Free water molecules move toward
a hypertonic solution.
If the amount of solutes (dissolved
molecules) in two solutions is equal,
the solutions are isotonic to each
other.
True
105
Active transport utilizes protein carriers that open
only when energy (ATP) is supplied.
True
106
Endocytosis
is the engulfing of substances outside of the cell in order to form a vesicle that is brought
inside the cel
107
Exocytosis
is the discharge of substances from vesicles at the inner surface of the cell.
