Campbell Biology, 12th edition- Chapter 1-6 study guide

What is biology

the study of living things

What is science?

An organized way of using evidence to learn about the natural world via experimentation, observation, and so on.

What are some characteristics of life?

reproduction; homeostasis; stimuli response; made of cells; based on universal code (DNA); able to develop and grow; be able to change over time; able to metabolize

Compare inductive to deductive reasoning.

Inductive: collecting and analyzing observations can lead to important conclusions, specific to general

Deductive: Used after a hypothesis has been developed, general to specific

What is a hypothesis?

A hypothesis is a statement that can be tested; an educated guess

What does it mean to control for variables?

Controlling for a variable' means measuring extraneous variables and accounting for them statistically to remove their effects on other variables.

What is the difference between an independent variable and a dependent variable? Be able to identify variables.

An independent variable is the input or factor manipulated to observe its effect, whereas a dependent variable is the output or response that is measured.

What is a theory?

a well-tested explanation for a broad set of observations

How is a theory different from a hypothesis?

a hypothesis is constructed before any applicable research has been done. A theory, on the other hand, is supported by evidence

What is a Chi-Square analysis? What questions can it answer?

The observed and expected values are compared using the chi-square statistic. This test statistic is utilized to determine whether there is a statistically significant discrepancy between the observed and expected values.

What is an element?

A pure substance that consists entirely of one type of atom

What are the key elements?

Carbon, Hydrogen Oxygen, and Nitrogen. (CHON)

What determines the properties of an element?

The number of electrons in its atom

What is an atom?

The smallest particle of an element.

What is atomic structure? List and describe the subatomic particles.

An extremely small, positively charged nucleus surrounded by a cloud of negatively charged electrons.

what are the subatomic particles?

protons, neutrons, electrons

What is valence?

The number of electrons in the outer shell

What is the expected result of a full valence shell?

Atoms are the most stable, least reactive

What are isotopes?

Atoms of the same element that have the same number of protons (atomic number) but a different number of neutrons,

What are chemical bonds?

An attraction between two or more atoms, and is what forms a chemical

How do chemical bonds form?

(chemical bonds form) by the attraction between the positive nucleus of one atom and the negative electrons of another atom

What is an ionic bond?

A chemical bond that's formed when an atom transfers an electron to another Atom (Weak)

What is a covalent bond?

Electrons are shared between two atoms. (Strong)

What is a non-polar bond?

a covalent bond in which electrons are shared equally

What is a polar bond?

a covalent bond in which electrons are shared unequally

What does it mean to be electronegative?

A measure of an atom's ability to attract shared electrons to itself. It makes bonding between atoms possible

What are hydrogen bonds?

An attraction between two atoms that already participate in other chemical bonds (Weak)

What is the difference between a strong bond and a weak bond?

Weak Bonds have less of a force of attraction between the atoms or molecules

While Strong Bonds, bond together very strongly they do so via either a covalent bond or an ionic bond.

What determines the shape of a molecule?

where the electrons and nuclei are located

What happens to matter as chemical reactions occur?

breaking chemical bonds between reactant molecules and forming new bonds between atoms in product particles.

What is chemical equilibrium?

a state in which the rate of the forward reaction equals the rate of the backward reaction

Describe the chemical structure of water

two hydrogen atoms and one oxygen atom

What kinds of bonds does water have internally?

hydrogen bonds

What kinds of bonds does one water molecule form with another water molecule?

hydrogen bonds

How does the ability of water to form hydrogen bonds affect its properties?

Hydrogen bonds cause water to be exceptionally attracted to each other. Therefore, water is very cohesive. We see evidence of water's cohesiveness every day - in water drops and in streams of water.

What emergent properties result due to the polarity of the water molecule?

the ability to stick to itself (cohesion), stick to other substances (adhesion), and have surface tension. All of this is due to Hydrogen bonding.

How does a high specific heat and high heat of vaporization impact cells? Organisms? The entire planet?

It helps prevent organisms from overheating due to the thermal energy released by chemical reactions inside cells. It helps organisms maintain a relatively stable internal temperature when the external temperature rises or falls.

Why does ice float on water? What does this mean for the planet?

Because ice is less dense than water, this top layer of ice floats on the liquid water below it.

What kinds of molecules can water dissolve?

Water is good at dissolving ions and polar molecules, but poor at dissolving nonpolar molecules.

Adhesion

the tendency of dissimilar particles or the ability of one thing to stick firmly to another

Cohesion

the sticking together of particles of the same substance.

Solvent

Any substance, usually liquid, which is capable of dissolving one or several substances, thus creating a solution.

Solute

A (Minor) substance that is dissolved in a solution.

Hydrophilic

A tendency to mix with, dissolve in, or be "wetted" by water.

Hydrophobic

Tending to repel or fail to mix with water an example being vegetable oil.

List three characteristics of the dissociation of water.

reversible- water dissociates and then re-associates

rare- at any given moment most molecules are H2O (99.999999999999999999% but it does happen all the time)

reactive- the ions WILL participate in a reaction, if it is pure water all they can do is re-form water but if it isn't pure water......

What are acids and bases?

An acid is any hydrogen-containing substance that is capable of donating a proton (hydrogen ion) to another substance. A base is a molecule or ion able to accept a hydrogen ion from an acid.

What is a pH scale? How does it work?

A measure of how acidic/basic water is.

What do the words strong and weak mean regarding acids and bases?

Strong acids and strong bases are entities that totally dissociate and produce ions in solution. In contrast, weak acids and bases ionize only partially, and the ionization reaction is reversible. As a result, weak acid and base solutions contain a mix of charged and uncharged species that are in dynamic equilibrium.

What are buffers? How do they work?

A solution that can resist pH change upon the addition of an acidic or basic components.

How does carbon bond?

Carbon can form single, double, or even triple bonds with other carbon atoms.

How does molecular diversity result?

Variations in the carbon skeleton

What are isomers?

one of two or more chemical compounds or groups that have the same numbers of atoms of the same elements but differ in structure

What is a Structural isomer?

One in which two or more organic compounds have the same molecular formulas but different structures

What is a Cis-trans isomer?

Molecules with the same connectivity of atoms. They feature same side groups placed on the same side of a double bond. Trans isomers feature molecules with same side groups placed on opposite sides of a double bond.

What is an Enantiomers isomer?

Enantiomers are pairs of compounds with exactly the same connectivity but opposite three-dimensional shapes.

What are the properties of Hydroxyl?

Hydroxyl groups are polar, and the oxygen side is always negative, while the hydrogen side is always positive. The hydroxyl group is an integral component of organic chemistry.

What are the properties of Carbonyl?

They exhibit both positive and negative charges in slight form. Hence, these are said to be polar molecules. These compounds are reported to be insoluble in water but sometimes they dissolve other forms of polar molecules.

What are the properties of Carboxyl?

A high melting point, hydrophilic centres, and boiling point

What are the properties of Amino?

They have a very high melting and boiling point.

What are the properties of Sulfhydryl?

low boiling point and moderate polarity.

What are the properties of Phosphate?

It has four hydrogen bond acceptors in the oxygen atoms. It is slightly soluble in water. Negatively charged

What are the properties of Methyl?

The ability to form non-polar covalent bonds and hydrophobicity.

What is Adenosine triphosphate (ATP) and what does it do?

The source of energy for use and storage at the cellular level.

What are macromolecules?

A molecule containing a very large number of atoms, such as a protein, nucleic acid, or synthetic polymer.

How are macromolecules formed? How are they disassembled?

Dehydration synthesis reactions build molecules up and generally require energy, while hydrolysis reactions break molecules down and generally release energy.

What are enzymes?

Proteins that help speed up metabolism, or the chemical reactions in our bodies

What are carbohydrates?

Any of a large group of organic compounds that includes sugars, starch, and cellulose, containing hydrogen and oxygen in the same ratio as water (2:1) and used as structural materials and for energy storage within living tissues.

How are Starch, Cellulose, and Glycogen the same?

Starch, cellulose, and glycogen are all forms of polysaccharides that consist of glucose subunits. However, they differ in their structures and functions. Starch and glycogen are composed of 𝜶-glucose subunits, while cellulose is made up of 𝛃-glucose subunits.

How are Starch, Cellulose, and Glycogen different?

It is made of monomers of beta glucose rather than alpha glucose. This seemingly small variation produces fundamental differences in the structure and function of this polysaccharide.

What are Starch, Cellulose, and Glycogen roles in an organism?

Storing energy in both animals and plants

What are lipids?

Any of a class of organic compounds that are fatty acids or their derivatives and are insoluble in water but soluble in organic solvents. They include many natural oils, waxes, and steroids.

Why are lipids hydrophobic?

Because all three substituents on the glycerol backbone are long hydrocarbon chains, these compounds are nonpolar and not significantly attracted to polar water molecules.

Fats (lipids)

Waxy, or oily compounds that are soluble in organic solvents and insoluble in polar solvents such as water

Phospholipids

major membrane lipids that consist of lipid bilayers.

Steroids

A man-made version of hormones normally produced by the adrenal glands

What is the difference between unsaturated and saturated fat?

Saturated fatty acids lack double bonds between the individual carbon atoms, while in unsaturated fatty acids there is at least one double bond in the fatty acid chain.

What are proteins?

large, complex molecules that play many critical roles in the body.

Describe an amino acid monomer

monomers that make up proteins

What determines the properties of an amino acid monomer?

The chemical composition of the side chain

What determines the properties of a protein?

the analogous properties of the amino acids in it.

Primary level of protein structure.

simply the sequence of amino acids in a polypeptide chain

Secondary level of protein structure.

regular, local structure of the protein backbone, stabilised by intramolecular and sometimes intermolecular hydrogen bonding of amide groups.

Tertiary level of protein structure.

the overall three-dimensional arrangement of its polypeptide chain in space.

Quaternary level of protein structure

the association of several protein chains or subunits into a closely packed arrangement.

What happens to a protein when it denatures?

The protein breaks down to monomers

What are nucleic acids?

large biomolecules that play essential roles in all cells and viruses

Describe the structure of nucleotide.

A nucleotide consists of a sugar molecule attached to a phosphate group and a nitrogen-containing base

Compare RNA and DNA

DNA is double-stranded, forming a double helix, while RNA is usually single-stranded.

What determines protein primary structure?

The sequence of amino acids linked together to form a polypeptide chain.

What is a cell?

The smallest unit that can live on its own and that makes up all living organisms and the tissues of the body.

What are the characteristics that all cells share?

A plasma membrane, cytoplasm, ribosomes, and DNA.

Why are cells limited in size?

Cell size is limited by the surface area to volume ratio of the cell. As the volume of a cell increases, it becomes harder to efficiently transport materials in and out of the cell.

Compare light microscopes to electron microscopes.

Electron microscopes differ from light microscopes in that they produce an image of a specimen by using a beam of electrons rather than a beam of light.

Compare eukaryotic to prokaryotic cells.

Prokaryotes are always unicellular, while eukaryotes are often multi-celled organisms. Additionally, eukaryotic cells are more than 100 to 10,000 times larger than prokaryotic cells and are much more complex. The DNA in eukaryotes is stored within the nucleus, while DNA is stored in the cytoplasm of prokaryotes.

What is a membrane? What is its role?

Provides protection for a cell. It also provides a fixed environment inside the cell, and that membrane has several different functions. One is to transport nutrients into the cell and also to transport toxic substances out of the cell.

Describe the nucleus and its functions.

serves both as the repository of genetic information and as the cell's control center. also responsible for DNA replication, transcription, and RNA processing, with only the final stage of gene expression localized to the cytoplasm.

Describe the nucleolus and its functions.

A spherical structure found in the cell's nucleus whose primary function is to produce and assemble the cell's ribosomes. Also where ribosomal RNA genes are transcribed.

Describe the nucleoid and its functions.

Essential for controlling the activity and reproduction of the prokaryotic cell. In this place transcription and replication of DNA take place. Binding proteins are abundant and have a lower molecular mass, binding proteins bind DNA and alter its shape.

Describe the ribosome and its functions.

An intercellular structure made of both RNA and protein, and it is the site of protein synthesis in the cell. It reads the messenger RNA (mRNA) sequence and translates that genetic code into a specified string of amino acids, which grow into long chains that fold to form proteins.