Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Bio Ch 2 > Bio Ch 3 > Flashcards

Bio Ch 3 Flashcards

(77 cards)

Start Studying
1
Q

What are the three main subatomic particles of an atom?

A

Protons, neutrons, electrons

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

What gives an atom its identity?

A

The number of protons

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

What does the atomic number represent?

A

The number of protons in an atom

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

What are the three states of matter?

A

Solid, liquid, gas

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

What is an element?

A

A substance that cannot be broken down to simpler substances by ordinary chemical means

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

How many naturally occurring elements are there?

A

92

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

What are isotopes?

A

Atoms of the same element that differ in the number of neutrons

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

What is the mass number of an atom?

A

The sum of protons and neutrons

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

Fill in the blank: The atomic mass unit (AMU) of electrons is _______.

A

Considered zero

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

True or False: The chemical behavior of a radioactive isotope is the same as that of stable isotopes of the same element.

A

True

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

What are the six elements that make up about 95% of the body weight of organisms?

A
  • Carbon
  • Hydrogen
  • Nitrogen
  • Oxygen
  • Phosphorus
  • Sulfur
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What does the acronym CHOPS help remember?

A

The six elements essential to life: Carbon, Hydrogen, Oxygen, Phosphorus, Sulfur

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

What can radiation from radioactive isotopes be used for in medicine?

A

Sterilizing medical and dental products

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

What does PET stand for in medical imaging?

A

Positron Emission Tomography

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

What is the charge and location of protons?

A

+1 charge, located in the nucleus

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

What is the charge and location of neutrons?

A

No charge, located in the nucleus

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

What is the charge and location of electrons?

A

-1 charge, located in the electron shell

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

What type of radiation can harm cells and cause cancer?

A

High levels of radiation

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

Fill in the blank: The atomic symbol for sodium is _______.

A

Na

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

What are the beneficial uses of radiation in biology?

A

Imaging and tracing the movement of substances through the human body

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

What is the significance of John Dalton in chemistry?

A

He championed the atomic theory in the early 1800s

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

What happens to carbon-14 over time?

A

It decays and releases radiation

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

What is the relationship between atomic mass and atomic weight?

A

Atomic mass is used rather than atomic weight due to variations with gravity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
True or False: The atomic symbol for carbon is C.
True
26
What does a PET scan help diagnose?
Brain tumors, Alzheimer's disease, epilepsy, strokes
27
What is the role of radiation in medical therapy?
Radiation therapy is used to kill cancer cells with little risk to the rest of the body.
28
What is a compound?
A compound is formed when atoms bond together. For example, water (H₂O) is a compound made of hydrogen and oxygen atoms.
29
What are the two types of radiation mentioned?
High-energy radiation and X-rays.
30
What happens to electrons during a chemical reaction?
Electrons shift in relation to one another, and energy may be given off or absorbed.
31
What is the difference between ionic and covalent bonding?
Ionic bonding involves the transfer of electrons, while covalent bonding involves sharing electrons.
32
What are ions?
Ions are charged particles formed when electrons are transferred between atoms.
33
What is the charge of a sodium ion?
A sodium ion (Na⁺) has a net charge of +1.
34
What is the charge of a chloride ion?
A chloride ion (Cl⁻) has a net charge of -1.
35
What are some examples of biologically important ions?
Sodium (Na⁺), chloride (Cl⁻), and potassium (K⁺) are examples of biologically important ions.
36
What is the significance of the thyroid scan?
A thyroid scan can indicate the presence of a tumor that does not take up radioactive iodine.
37
What does a PET scan reveal?
A PET scan reveals which portions of the brain are most active.
38
How do atoms achieve stability?
Atoms achieve stability by forming bonds with other atoms, resulting in molecules or compounds.
39
What causes the hydrogen atoms in one water molecule to be attracted to the oxygen atoms in other water molecules?
Polarity within a water molecule causes this attraction. ## Footnote This attraction is called a hydrogen bond.
40
How does water's heat capacity compare to other covalently bonded liquids?
Water has a high heat capacity, requiring a significant amount of energy to raise its temperature compared to other liquids.
41
What is the energy required to convert 1 g of liquid water to gas?
Converting 1 g of the hottest water to gas requires an input of 540 calories of heat energy.
42
What is the effect of hydrogen bonds on the temperature of water?
Hydrogen bonds help water absorb heat without a great change in temperature, allowing it to maintain a stable temperature.
43
How do hydrogen bonds contribute to the stability of DNA?
Hydrogen bonds hold the two strands of DNA together, adding stability to the DNA molecule.
44
What happens to body heat when an animal sweats?
Body heat is used to vaporize the water, thus cooling the animal.
45
Why are coastal temperatures moderate?
Coastal temperatures are moderate due to water's high heat capacity and high heat of vaporization.
46
What is a solution?
A solution contains dissolved substances called solutes.
47
What happens when ionic salts are put into water?
The negative ends of the water molecules are attracted to the sodium ions, and the positive ends are attracted to the chloride ions, causing them to dissociate.
48
What percentage of organisms is composed of water?
Organisms are composed of 70 to 90% water.
49
What would happen to water without hydrogen bonding?
Water would change from a solid to liquid state at -100°C and from a liquid to gaseous state at -91°C.
50
What are the melting and boiling points of water?
Water melts at 0°C and boils at 100°C.
51
What is a hydrophilic molecule?
Molecules that can attract water are said to be hydrophilic.
52
What is a hydrophobic molecule?
Nonionized and non-polar molecules, such as oil, that cannot attract water are said to be hydrophobic.
53
What is cohesion in water?
Cohesion is the property that allows water molecules to cling together due to hydrogen bonding.
54
What is adhesion in water?
Adhesion is the property that allows water to adhere to polar surfaces.
55
How does water function in living organisms?
Water serves as an excellent transport system for nutrients and waste molecules in both unicellular and multicellular organisms.
56
What role does water play in plants?
Water is absorbed by the roots and transported to the leaves, where it is lost through evaporation.
57
What happens to water when it freezes?
Water expands when it freezes because the water molecules in ice form a lattice that is less dense than liquid water.
58
What is the pH scale?
The pH scale is used to indicate the acidity or basicity of solutions, ranging from 0 to 14.
59
What is a strong acid?
A strong acid is one that dissociates almost completely in water, such as hydrochloric acid (HCl).
60
What is a strong base?
A strong base is one that dissociates almost completely in water, such as sodium hydroxide (NaOH).
61
What is the relationship between pH and hydrogen ion concentration?
As pH decreases, the concentration of hydrogen ions (H+) increases.
62
What is the significance of ice floating on water?
Ice floats on water because it is less dense than liquid water, which prevents bodies of water from freezing solid.
63
What is the role of hydrogen bonding in water's properties?
Hydrogen bonding contributes to water's high surface tension and cohesive properties.
64
What is the formula for a hydrogen ion?
A hydrogen ion is often simply called a proton (H+).
65
What is the pH scale range?
The pH scale ranges from 0 to 14, with 0 being the most acidic and 14 being the most basic.
66
What pH value represents a neutral solution?
A pH of 7 represents a neutral state where hydrogen ion (H+) and hydroxide ion (OH-) concentrations are equal.
67
What indicates an acidic solution on the pH scale?
A pH below 7 indicates an acidic solution because the hydrogen ion concentration [H+] is greater than the hydroxide concentration [OH-].
68
What indicates a basic solution on the pH scale?
A pH above 7 indicates a basic solution because the hydroxide concentration [OH-] is greater than the hydrogen ion concentration [H+].
69
What is the relationship between pH values and hydrogen ion concentration?
As we move down the pH scale from pH 14 to pH 0, each unit has ten times the H+ concentration of the previous unit.
70
What is a buffer?
A buffer is a substance that keeps pH within normal limits by taking up excess hydrogen ions (H+) or hydroxide ions (OH-).
71
What is the pH of healthy blood?
The pH of healthy blood is always about 7.4, which is slightly basic (alkaline).
72
What happens if blood pH drops to about 7?
If the blood pH drops to about 7, acidosis results.
73
What is the definition of pH?
pH is defined as the negative log of the hydrogen ion concentration [H+].
74
What is an example of a common basic solution?
Baking soda and antacids are common basic solutions familiar to most people.
75
What is sodium hydroxide (NaOH)?
Sodium hydroxide (NaOH) is an important base that dissociates into Na+ and OH- in solution.
76
What is the significance of sodium hydroxide's dissociation?
Because dissociation is almost complete, sodium hydroxide is called a strong base.
77
How does ice behave compared to water?
Ice floats on water because water expands when it freezes, forming a lattice with hydrogen bonds farther apart than in liquid water.

Bio Ch 2 (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions