Exam 1 Study Guide Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What is Biology?

A

Biology is the scientific study of life

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

List and describe the characteristics of life.

A

1) Presence of cells
2) Order: biological hierarchy
3) Response to the physical environment
4) Energy processing
5) Evolution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Describe how energy flows through an ecosystem. Where does the energy come from, how is it processed, and how in what form does it leave?

A

Energy flows through an ecosystem, usually entering as light and exiting as heat

  • The “light” mentioned here is sunlight
  • When you move, some of that energy is released as heat, thats how we regulate our body temperature
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What characteristics do eukaryotic and prokaryotic cells have in common? How do they differ?

A

All cells have a plasma membrane, ribosomes, cytoplasm, and DNA. The primary distinction between these two types of organisms is that eukaryotic cells have a membrane-bound nucleus and prokaryotic cells do not.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the taxonomic groups that we use to classify living organisms? Which group is more general? Which is least general?

A

(most general to more specific): Domain, Kingdom, Phylum, Class, Order, Family, Genus, species

For help: Dumb Kings Play Chess On Fine Glass Squares

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How is taxonomy used in the study of evolution?

A

It helps identify biological specimens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

State the three domains of life.

A

1) Bacteria
2) Archaea
3) Eukarya

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe the role that DNA plays in the growth, development, and reproduction.

A

DNA contains the instructions needed for an organism to develop, survive and reproduce.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Compare positive and negative feedback.

A

Negative feedback: as more of a product accumulates, the process that creates it slows, and less of the product is produced

Positive feedback: as more of a product accumulates, the process that creates it speeds up and more of the product is produced

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

State and describe the steps of the scientific method.

A

The scientific process includes:

  • Making observations
  • Forming logical hypotheses
  • Testing hypotheses through experimentation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What does it mean that a hypothesis must be testable and falsifiable?

A

A hypothesis is called falsifiable if it is possible to conceive of an experimental observation that disproves the idea in question.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe what Darwin meant by “descent with modification” and “natural selection.”

A

Descent with modification: Organisms are modified descendants of common ancestors

Natural selection:

  • Individuals in a population vary in their traits, many of which are heritable
  • More offspring are produced than survive, and competition is inevitable
  • Species generally suit their environment
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Can traits acquired over the course of an organism’s life be passed on to its offspring?

A

Acquired traits are not coded in the DNA of an individual and therefore most scientists believe they cannot be passed down to offspring during reproduction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How are evolutionary trees used to describe the evolutionary history of organisms?

A

The branches themselves connect up in a way that represents the evolutionary history of the species—that is, how we think they evolved from a common ancestor through a series of divergence (splitting-in-two) events.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Nutrient cycling

A

a cyclic process that encompasses the movement of nutrients from the physical environment to living organisms and back to the environment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

chromosome

A

A carrier of genetic information that is found inside the nucleus of a cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

gene

A

the basic physical and functional unit of heredity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

theory

A
  • Broader and more general in scope than a hypothesis

- Supported by a large body of evidence in comparison to a hypothesis and can lead to new testable hypotheses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

hypothesis

A

A hypothesis is a tentative answer to a well-framed question

- A scientific hypothesis leads to predictions that can be tested by observation or experimentation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is matter?

A

anything that takes up space and has mass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is an atom?

A

the smallest unit of matter that still has chemical characteristics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is an element?

A

a pure substance that cannot be broken down to other substances by chemical reactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Which four elements make up 96% of human body mass?

A

carbon (C), hydrogen (H), oxygen (O), and nitrogen (N)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is a compound?

A

A material made up of two or more parts or elements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is a molecule?

A

a group of atoms that form the smallest identifiable unit into which a pure substance can be divided and still retain the composition and chemical properties of that substance.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Describe these subatomic particles of the atom: proton; neutron, electron.

A

Proton: a positively charged particle that resides in the nucleus of an atom

Neutron: an uncharged elementary particle that has a mass nearly equal to that of the proton

Electron: a stable atomic particle that has a negative charge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

If a normal atom of an element has 6 protons: a) which element is it? b) how many electrons will it usually have? c) how many neutrons will it usually have?

A

a) carbon
b) 6 electrons
c) 6 electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is a Dalton?

A

unit used to express molecular mass

  • Neutron mass and proton mass are measured in daltons
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

How are an element’s atomic number and atomic mass determined?

A

An element’s atomic number = # of protons in its nucleus

An element’s mass number = protons + neutrons in the nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

If Cl has 17 electrons, 17 protons, and 18 neutrons, what is its mass number?

A

mass number = 35

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What are valence electrons? How do they affect the bonding potential of an element?

A

Valence electrons are those in the outermost shell, or valence shell.

Atoms with incomplete valence shells can share or transfer valence electrons with certain other atoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Calculate the valence of the following elements: C, O, H, N.

A

carbon: 4
oxygen: 6
hydrogen: 1
nitrogen: 5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What are isotopes? Describe how scientists can use radioactive isotopes.

A

Isotopes are two atoms of an element that differ in the number of neutrons.

Radioactive isotopes decay spontaneously, giving off particles and energy; have applications in biological research

  • Dating fossils
  • Diagnosing medical disorders
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Describe covalent bonds. What do you call compounds that form from covalent bonds?

A

A covalent bond is the sharing of a pair of valence electrons by two atoms

Molecular compounds form from covalent bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is electronegativity?

A

a measure of an atom’s ability to attract shared electrons to itself.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Are the shared electrons distributed evenly between the atoms in a covalent bond?

A

In pure covalent bonds, the electrons are shared equally.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What is a polar versus nonpolar covalent bond? How do the properties of polar and nonpolar molecules differ?

A

nonpolar: electrons are shared equally. polar: electron sharing is unequal.

Polar molecules have positive and negative ends which nonpolar do not.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What is an ionic compound? How do ionic bonds form?

A

An ionic bond is formed by the complete transfer of some electrons from one atom to another.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What is an ion? What do you call an ion with a positive charge? What do you call an ion with a negative charge?

A

A charged atom (or molecule) is called an ion.

Negative ion: anion; positive ion: cation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What is a hydrogen bond? How does it form? Is it weaker or stronger than a covalent bond?

A

A hydrogen bond forms when a hydrogen atom covalently bonded to one electronegative atom is also attracted to another electronegative atom.

It is weaker than a covalent bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What is a chemical reaction? Describe a reversible reaction? What happens when the relative amounts of product and reactants stabilize?

A

Chemical reactions make or break chemical bonds
- Chemical reactions start with materials called reactants and produce materials called products

All chemical reactions are theoretically reversible
The products of the forward reaction become the reactants for the reverse reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

trace elements

A

Trace elements are those required by an organism in minute quantities

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

orbital

A

Electron orbitals are three-dimensional representations of the space in which an electron is likely to be found.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

single bond

A

single bond: shares one pair of valence electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

double bond

A

Double bond: shares two pairs of valence electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Describe the four emergent properties of water that contribute to Earth’s fitness for life.

A

1) Cohesive behavior
- water sticks to itself

2) ability to moderate temperature
- keeps things from becoming too cold or too hot

3) expansion upon freezing

4) versatility as a solvent
- universal solvent of life

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What properties of water do plants use to move water against gravity?

A

adhesion and cohesion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What type of energy is temperature used to measure? How do fluctuations of temperature affect the movement of molecules?

A

heat energy

Temperature change in water will first break hydrogen bonds before heat is absorbed by the water molecules, leading to evaporation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What is specific heat? What is the specific heat of water?

A

Specific heat is the amount of heat one gram of a substance must absorb or lose to change its temperature by one degree Celsius.

For water, this amount is one calorie.

50
Q

What is the heat of vaporization?

A

the amount of heat needed to turn 1g of a liquid into a vapor.

51
Q

How do the properties of solid water differ from those of liquid water?

A

water’s solid form (ice) is less dense than its liquid form.

52
Q

What are the differences between hydrophobic and hydrophilic molecules?

A

A hydrophilic substance is one that has an affinity of water

A hydrophobic substance is one that does not have an affinity for water

53
Q

mole

A

One mole = number of daltons per molecule.

54
Q

molarity

A

the number of moles per liter of solution

55
Q

Define acids and bases

A

An acid is any substance that increases the H+ concentration of a solution

A base is any substance that reduces the H+ concentration of a solution

56
Q

What effect does H+ ion concentration have on the pH of a solution?

A

High concentrations of hydrogen ions yield a low pH (acidic substances), whereas low levels of hydrogen ions result in a high pH (basic substances).

57
Q

What is the pH scale? How is it used to determine how acidic or basic a solution is?

A

Neutral solution = 7
acidic solution = less than 7
basic solution = greater than 7

58
Q

How does a buffer regulate pH in a living organism?

A

substances that minimize changes in concentrations of H+ and OH- in a solution

59
Q

cohesion

A

the attraction of molecules for other molecules of the same kind

60
Q

adhesion

A

an attraction between different substances

61
Q

aqueous

A

one in which water is the solvent

62
Q

hydration shell

A

The sphere of water molecules around each dissolved Ion.

63
Q

hydrogen ion

A

created when a hydrogen atom loses or gains an electron. (Hydrogen ion symbol: H+)

64
Q

hydroxide ion

A

a polyatomic ion consisting of oxygen and hydrogen (OH-)

65
Q

hydronium ion

A

water molecules that have gained an extra positive hydrogen ion.

66
Q

What is an organic compound?

A

carbon-based compounds (covalently bonded to carbon)

67
Q

What is the valence of carbon? How many single, covalent bonds can carbon form? How does carbon’s valence give it the ability to form large, complex molecules?

A

the valence of carbon is 4 so it can form 4 covalent bonds.

Carbon has a strong tendency to form covalent bonds with other atoms in order to complete its octet.

68
Q

What are hydrocarbons? Are they polar or non-polar?

A

any of a class of organic chemicals made up of only the elements carbon (C) and hydrogen (H). They are non-polar

69
Q

structural isomer

A

molecules with the same molecular formula, but their atoms have different arrangements or bonds.

70
Q

Cis-Trans isomer

A

Cis-trans isomers have the same covalent bonds but differ in spatial arrangements

71
Q

Enantiomer

A

Enantiomers are isomers that are mirror images images of each other

72
Q

Hydroxyl group

A

attaches to molecules containing an oxygen and hydrogen atom, bonded together.

73
Q

carbonyl group

A

A carbon atom double-bonded to an oxygen

74
Q

carboxyl group

A

a carbon atom that’s double-bonded to an oxygen atom and singly bonded to a hydroxyl group

75
Q

amino group

A

nitrogen atom connected by single bonds to hydrogen or carbon.

76
Q

sulfhydryl group

A

An R group bound to a sulfur atom and a hydrogen atom

77
Q

phosphate group

A

phosphorus attached to four oxygen

78
Q

methyl group

A

made of one carbon and three hydrogen atoms.

79
Q

Describe dehydration synthesis and hydrolysis.

A

A dehydration reaction occurs when two monomers bond together through the loss of a water molecule

Polymers are disassembled to monomers by hydrolysis, a reaction that is essentially the reverse of the dehydration reaction
- Lyse: to break apart

80
Q

Which macromolecules always contains N?

A

proteins and nucleic acids

81
Q

Which functional groups are found in all proteins?

A

amino group

82
Q

What are carbohydrates used for in the body?

A

help in producing energy

83
Q

What is the name of the covalent bond between monosaccharides?

A

glycosidic linkage

84
Q

Describe monosaccharides, disaccharides, and polysaccharides.

A

monosaccharides are monomers of sugars and disaccharides are composed of two monomers whereas polysaccharides are composed of a large number of monomers.

85
Q

What is glucose? How many carbon atoms are in a molecule of glucose? What is glucose used for in the cell?

A

Glucose is the main type of sugar in the blood and is the major source of energy for the body’s cells. Glucose has 6 carbon atoms.

86
Q

What is starch? What do plants use starch for? What monosaccharide do we obtain from hydrolysis of starch?

A

Starch is found in plants and used to store energy. It serves the plant as a reserve food supply.

Maltose is produced by the enzymatic hydrolysis of starch.

87
Q

What is cellulose? Which organisms produce cellulose? How is it different from starch? What is its function: a) in plants, b) in animals?

A

Cellulose is a molecule consisting of carbon, hydrogen, and oxygen atoms.

Cellulose is used for structural support whereas starch is used for energy storage.

Cellulose is the main substance in the walls of plant cells. Humans cannot digest cellulose, but it is important in the diet as a fiber.

88
Q

What characteristic is used to group lipids?

A

hydrophobic molecules

89
Q

Describe the three types of lipids.

A

1) fats: store energy
2) Phospholipids: cell membranes
3) Steroids: cholesterol, testosterone, estradiol

90
Q

What is glycerol? What is a fatty acid?

A

Glycerol is a three-carbon alcohol with a hydroxyl group attached to each carbon

A fatty acid consists of a carboxyl group attached to a long carbon skeleton

91
Q

What is the name of the covalent bond is used to attach fatty acids to glycerol in triglycerides? What are fats used for in the body? Compare and contrast saturated and unsaturated fats.

A

ester linkage

Fat is a source of essential fatty acids, which the body cannot make itself.

Saturated fats are solid at room temperature. Unsaturated fats are liquid at room temperature.

92
Q

Describe the structure and function of phospholipids. How do phospholipids behave in an aqueous solution? What are phospholipids used for in the body?

A

The structure results in a bilayer arrangement found in cell membranes.

in an aqueous solution, they self-assemble into a bilayer, with the hydrophobic tails pointing toward the interior.

Phospholipids are structural components of cell surface membranes

93
Q

Describe the structure and function of steroids. What are some purposes of cholesterol?

A

Steroids are lipids characterized by a carbon skeleton consisting of four fused rings

Cholesterol is used to produce estradiol and testosterone

94
Q

What are some major functions of proteins?

A

They do most of the work in cells and are required for the structure, function, and regulation of the body’s tissues and organs.

95
Q

Describe the structure of amino acids. What does the ‘R’ group on an amino acid determine?

A

made up of a basic amino group, an acidic carboxyl group, and an organic R group

The R group determines the characteristics for each type of amino acid.

96
Q

How do polymers of amino acids form or break apart? What is the name of the covalent bond between amino acids?

A

Polymers are broken down into monomers in a process known as hydrolysis.

Peptide bonds

97
Q

Describe the 4 levels of protein organization.

A

1) primary structure
2) secondary structure
3) tertiary structure
4) quaternary structure

98
Q

What types of proteins catalyze chemical reactions?

A

enzymes

99
Q

State the two types of nucleic acids.

A

Deoxyribonucleic acid (DNA)

Ribonucleic acid (RNA)

100
Q

How do DNA and RNA interact to produce proteins?

A

DNA makes RNA and RNA makes Protein.

101
Q

Describe the 3 components of a nucleotide.

A

phosphate, sugar molecule, and one of four bases.

102
Q

What are the 5 nitrogenous bases?

A

adenine (A), thymine (T), cytosine (C), and guanine (G).

103
Q

Which bases are complementary between DNA strands, DNA and RNA strands?

A

bases for RNA — adenine (A), thymine (T) cytosine (C), and guanine (G) — are also found in DNA. In RNA, uracil (U) replaces thymine (T)

104
Q

Macromolecule

A

large biological molecules

105
Q

monomer

A

small building-block molecules

106
Q

polymer

A

a long molecule consisting of many similar building blocks

107
Q

glycosidic linkage

A

when a dehydration reaction joins two monosaccharides

108
Q

fatty acid

A

the building blocks of the fat in our bodies and in the food we eat.

109
Q

ester bond

A

The bond between the glycerol and fatty acids in lipids between an oxygen molecule and a carbon molecule.

110
Q

phosphate

A

a salt or ester of phosphoric acid.

111
Q

triglyceride

A

consists of a glycerol backbone esterified with three fatty acids.

112
Q

enzyme

A

a biological catalyst

113
Q

catalyst

A

any substance that increases the rate of a reaction without itself being consumed.

114
Q

polypeptide

A

a polymer of amino acids joined together by peptide bonds

115
Q

polynucleotides

A

a compound comprised of several nucleotides

116
Q

purine and pyrimidine

A

the two chemical compounds that cells use to make the building blocks of DNA and RNA

117
Q

nucleoside

A

the structural subunit of nucleic acids such as DNA and RNA.

118
Q

peptide bond

A

when the carboxyl group of one molecule reacts with the amino group of the other molecule, releasing a molecule of water

119
Q

denaturation

A

the breaking of many of the weak linkages, or bonds within a protein molecule

120
Q

double helix

A

a description of the molecular shape of a double-stranded DNA molecule