BIO112 (copy)

EXAM 1 STUDY GUIDE

The five fundamental characteristics of life?

cellular organization, replication/reproduction, information, metabolism/energy, adaptation through evolution

Pasteur’s experiment proved that

preexisting cells in the air can grow in sterilized nutrient broth/supporting cell theory/ disproving spontaneous generation

Recall Pasteur's experiment on spontaneous generation. If he had just warmed the nutrient- rich broth, rather than boiled it, what would have been the likely outcome of his experiment? Cells would

have appeared in both flasks

The discovery of the structure of DNA was use because

it suggested a mechanism for copying and preserving the genetic material

What are some evidence of the common ancestry of all life?

molecular and genetic similarities like the universal DNA/genetic code, anatomical similarities (homologous structures), the fossil record showing transitional forms and changes over time, biogeographical patterns of species distribution, and observations from embryology and comparative anatomy

What features describes the logic of scientific inquiry?

if my hypothesis is correct, I can expect certain test results

What is the difference between scientific hypotheses and scientific theories? 

hypotheses usually are relatively narrow in scope; theories have broad explanatory power/ hypotheses are untested while theories are tested

A friend of yours calls to say that his car would not start this morning. He asks for your help. You say that you think the battery must be dead. If so, then jump starting the car from a good battery will solve the problem. In doing so, you are

stating a hypothesis and using that hypothesis to make a testable prediction

Recall the experiment on ant navigation. To run a controlled experiment, what parameters were held constant for the test group of 75 ants?

All variables except leg length

In an attempt to examine the idea of spontaneous generation, Pasteur conducted experiments utilizing different shaped flasks. Upon designing the study, he noted "that if cells come only from preexisting cells, then the different shapes of flasks would produce different growth observation," which served as the _______ of the study

hypothesis

Some differences between eukaryotes and prokaryotes

prokaryotes lack a membrane-bound nucleus and organelles, with their DNA located in a central region called the nucleoid, while eukaryotes have a true nucleus that houses their DNA and possess various membrane-bound organelles like mitochondria and the Golgi apparatus

What are the qualities of a good scientific hypothesis

testable, meaning it can be investigated through experiments or observation, and falsifiable, meaning there's a possible way to prove it wrong. It is also specific, clearly defining the variables and expected outcome, and grounded in existing knowledge or theory, providing a clear prediction of a relationship between variables

The cell theory states that all cells come from preexisting cells. If this is the case, why are the cells in a multicellular organism so different from one another?

The genetic information of each cell is copied and passed on to the daughter cells and the molecular machinery that reads that genetic information is different in each cell.

Double helical DNA

used to synthesize messenger RNA

How does energy acquisition vary among organisms? (define autotroph, heterotroph)

Autotrophs create their own energy, while heterotrophs must consume other organisms for sustenance

List the classic Linnaean ranks for animals, from largest and most inclusive to smallest and least inclusive

domain, kingdom, phylum, class, order, family, genus, species

About 25 of the 92 natural elements are known to be essential to life. Which 4 of these 25 elements make up approximately 96 percent of living matter?

carbon, hydrogen, nitrogen, and oxygen

Why is each element unique with respect to its chemical properties? Each element has a distinctive ________.

number of protons

carbon-12 is the most common isotope of carbon and has a mass number of 12. however, the average atomic mass of carbon found a periodic table is slightly more than 12 daltons. why?

Some carbon atoms in nature have more neutrons.

From its atomic number of 15, it is possible to predict that the phosphorus atom has

15 protons and 15 electrons

A covalent chemical bond is one in which

Outer shell electrons are shared by two atoms so as to satisfactorily fill the outer electron shells of both.

Nitrogen (N) is more electronegative than hydrogen (H). Which of the following is a correct statement about the atoms in ammonia (NH3)?

Each hydrogen atom has a partial positive charge; the nitrogen atom has a partial negative charge.

Bonds between two atoms that are equally electronegative are _____.

nonpolar covalent bonds

how many electrons are involved in a single covalent bond

Two

Elements found on the left side of the periodic table contain outer shells that are _____; these elements tend to form _____ in solution.

almost empty; cations

An atom has four electrons in its valence shell. What types of covalent bonds is it capable of forming?

single, double, or triple

You need to write down information about a molecule, but need to indicate only the type and number of atoms it contains. Which representation would work best?

A molecular formula

You need to represent a molecule to best illustrate the relative sizes of the atoms involved and their interrelationships. Which representation would work best?

space-filling model

The complexity and variety of organic molecules is due to

the chemical versatility of carbon atoms

which functional group acts most like an acid in water

carboxyl

compounds containing which functional groups would be most likely to behave in a polar manner

Both hydroxyl and carboxyl

Stanley Miller's 1953 experiments supported the hypothesis that:

organic molecules can be synthesized abiotically under conditions that may have existed on early Earth.

Which of the following is a property of liquid water? Liquid water _____.

has a heat of vaporization that is higher than that for most other substances

A solution with a pH of 5 has how many more protons in it than a solution with a pH of 7?

100 times

A solution contains 0.0000001 (10-7) moles of hydroxyl ions [OH-] per liter. Which of the following best describes this solution?

neutral

the unique property of water that allows ice to float and prevents lakes from freezing solid is

Ice floats in liquid water because it has a lower density due to the stable hydrogen bonds forming a lattice structure/ anomalous expansion

what are some conditions that tends to make chemical reactions spontaneous

A chemical reaction is spontaneous when the reactants have lower potential energy than the products, aligning with the principle that a system tends to move from a state of higher to lower potential energy. The reactants are more ordered than the products.

what type of bond must be broken for water to vaporize?

Hydrogen bonds

a water strider can walk on the surface of a pond because of

high surface tension of the waters surface

the ability of water to absorb a lot of heat before the temperature rises significantly is known as its

high specific heat capacity

what are the components of each monomer used to make proteins

central carbon atom, an amino group (–NH₂), a carboxyl group (–COOH), a hydrogen atom, and a unique side chain known as an R-group

what component of amino acid structure varies among different amino acids?

the R group, also known as the side chain

at about ph 7 in most cells what happens to the amino group on an amino acid

acts as a base and gains a proton, acquiring a positive charge

At about pH 7 in most cells, what happens to the carboxyl group on an amino acid?

acts as an acid and loses a proton, giving it a negative charge

A peptide bond _____

forms the primary structure of proteins

The bonding of two amino acid molecules to form a larger molecule requires the _____.

release of a water molecule

there are 20 different amino acids. what makes one amino acid different from another?

different side chains (R groups) attached to carbon

Which two functional groups are always found in amino acids?

the amino group (-NH₂) and the carboxyl group (-COOH)

which type of interaction stabilizes the alpha helix and the beta pleated sheet structures of proteins

Hydrogen bonds

You are studying a protein that is shaped like a doughnut. The shape is a function of which level(s) of protein structure?

primary, secondary, and tertiary

a series of hydrophobic side chains will congregate together as protein folds in an aqueous solution and be stabilized by

van der Waals interactions

the tertiary structure of a protein is the _____

unique three-dimensional shape of the fully folded polypeptide

At which level of protein structure are interactions between the side chains (R groups) most important?

tertiary

the structural level of a protein least affected by a disruption in hydrogen bonding is the

primary

Which level of protein structure do the α helix and the β pleated sheet represent?

the α helix and the β pleated sheet represent the SECONDARY level of protein structure

suppose you discover a new amino acid. its r group contains only hydrogen and carbon atoms. predict the behavior of this atom

it is nonpolar hydrophobic

why does a fever become dangerous to body functions if it continues to rise

Proteins become denatured and are unable to complete their jobs.

Some functions of proteins in biological systems

enzymes, provide structural support, act as signaling molecules and receptors, transport materials, facilitate movement, serve as a defense mechanism, and store nutrients

amino acid side chain characteristic

nonpolar, polar uncharged, acidic (negatively charged), and basic (positively charged)

What is a peptide bond

The covalent chemical bond that forms between the carboxyl group of one amino acid and the amino group of another amino acid.

Nucleic acids are polymers made up of which of the following monomers?

Nucleotides

What is the difference between a ribonucleotide and a deoxyribonucleotide?

Ribonucleotides have a hydroxyl group on the 2 carbon of their sugar subunit.

What is/are the variable structure(s) of a nucleotide?

the sugar and the base

Which of the following includes all of the pyrimidines found in RNA and DNA?

cytosine, uracil, and thymine

Which of the following are purine nitrogenous bases?

guanine and adenine

What feature of single nucleotides provides the energy needed for polymerization when
nucleic acids are formed?

Their phosphate groups

Which of the following best describes DNA's secondary structure?

double antiparallel helical strands

A double-stranded DNA molecule contains a total of 120 purines and 120 pyrimidines. This
DNA molecule could be composed of ________.

120 adenine & 120 thymine or 120 cytosine & 120 guanine

Large amounts of DNA typically wrap around large proteins called ______________; this forms the ______________ structure of DNA.

histones;tertiary

Which of the following descriptions best fits the class of molecules known as nucleotides?

a nitrogenous base, a phosphate group, and a sugar

if the guanine content of a certain segment of DNA is 28% what is the adenine content

22%

The sequence of one strand of DNA is shown below. What is the sequence of its complementary strand? 5' - GGCCAAAT - 3'

3'-CCGGTTTA-5'