biology class normal lecture exams

A human heart cell contains ________ chromosomes.

46

Hemophilia is an X-linked recessive condition. If a female is a carrier for hemophilia, what percentage of her sons will be affected by the condition?

50%

If you conduct a monohybrid cross of two heterozygous Yy pea plants, what percentage of the offspring will be heterozygous?

50%

If you cross RrYy and RRyy pea plants, what percentage of the offspring will have round yellow peas? R = round, r = wrinkled, Y = yellow, y = green.

50%

The reactions of photosynthesis may be summarized as

6CO2 + 6H2O → C6H12O6 + 6O2

Meiosis is a process that produces

All of the answer choices are correct

A theory differs from a hypothesis in that a theory

All of the answer choices are correct.

Active transport is different from simple diffusion in that active transport

All of the answer choices are correct.

Alcoholic fermentation

All of the answer choices are correct.

Cells need increased surface area for diffusion of nutrients and wastes. Cells increase their surface area by

All of the answer choices are correct.

RNA differs from DNA in that

All of the answer choices are correct.

The process of phosphorylation

All of the answer choices are correct.

Which organism depends on photosynthesis for its life?

All of the answer choices are correct.

Which of the following is not true about a hypothesis?

It can be proven to be true.

Which of the following is not a description of the cell membrane?

It is a rigid structure.

Which of the following is not an example of a defining characteristic of life?

Organisms require oxygen

The four kingdoms included in the domain Eukarya are

Protista, Fungi, Plantae, and Animalia.

The property of water demonstrated by a water strider, as it remains on top of the water, is that water molecules are held together by ionic bonds.

false

A eukaryotic cell

has membrane-bounded organelles.

During DNA replication, the enzyme that unwinds and separates the DNA double-helical molecule is

helicase

If the two alleles for a particular gene are identical the gene pair is

homozygous

In living cells, a process by which cells break polymers down into monomers with the addition of water is

hydrolysis.

During fermentation, ________ ATP can be produced per glucose, compared with theoretical a yield of ________ by aerobic respiration.

2; 36

Which of the following RNA strands is complementary to the DNA sequence 5'-ATCGATCG-3'?

3'-UAGCUAGC-5'

If the DNA in a cell consists of 20% A, it will be ________ G.

30%

Which statement is not part of the first law of thermodynamics?

Any energy transformation loses some energy to its surroundings as heat.

The kingdom is the most all-inclusive taxonomic category.

False

If a pea plant is heterozygous for yellow seeds (Gg), the gametes will have which of the following allele(s)?

G or g

Why does sexual reproduction produce more genetic variability in a population than asexual reproduction?

Sexually reproducing organisms mix parental genetics in addition to crossing-over and random alignment.

Why is there a wide variation in skin color in humans?

Skin color is a polygenic trait.

Identify the largest distinction between the theory of spontaneous generation and the cell theory.

Spontaneous generation proposes life can form from available molecule components, while the cell theory explains how all cells are formed from preexisting cells.

All carbohydrate molecules

are composed of atoms of C, H, and the functional group -OH.

A healthy, young couple are both carriers of cystic fibrosis; the chance that each of their future children will inherit this serious illness is

25%.

Given this information from one element in the periodic table of elements, the number of neutrons and protons is 7 ; Nitrogen;N; 14.0067

14, which is also the atomic mass.

Having the typical ratio of carbon, hydrogen, and oxygen of carbohydrates, the chemical formula for glucose is

C6H12O6.

Referring to the ionic bond formation between sodium and chlorine, which of the following is not a true statement?

Chlorine donates an electron.

Of the following statements, which does not correlate a type of RNA with its function?

Complementary RNA reorders the amino acids to insure their correct sequence.

The enzyme that adds nucleotides to the 3' end of a growing DNA strand is called

DNA polymerase.

The process by which DNA is reproduced, with the use of associated enzymes, is

DNA replication.

"Life" is defined for any particle, substance, or object as anything which is not dead.

False

A somatic mutation is a mutation that occurs in cells that give rise to gametes.

False

A substance in which other substances dissolve is called a solute.

False

A theory is an advanced hypothesis that has been proven to be true.

False

The person who made a lasting impression in the science of genetics with his study of traits in pea plants was

Gregor Mendel.

Blood is closely maintained at a pH of 7.4. A patient whose blood pH drops below 7.35 is suffering from metabolic acidosis and can go into a coma. What happens to the concentration of H+ ions in a patient with a blood pH of 6.4?

H+ concentration is increased 10-fold.

Water molecules exhibit cohesive and adhesive properties. What is the chemical bond characteristic that contributes to these and other numerous important properties of water molecules?

Hydrogen bonds form between water molecules, not requiring gain, loss, or sharing of electrons.

A man with type A blood and a woman with type B blood have a child with type O blood. What are the genotypes of the man and woman?

IAi and IBi

Of the following, which statement is false regarding the characteristics of mitochondria?

Mitochondria carry out photosynthesis.

Which statement summarizes the distinction between nonpolar and polar covalent bonds?

The electrons are more evenly and symmetrically distributed in orbit among atoms in a nonpolar covalent bond.

In an experiment, which of the following is not generally a true statement?

The smaller the sample size the more reliable the results.

Cohesion is a property of water in which water molecules tend to stick together.

True

If a protein is denatured, its structure has been changed enough to make the protein nonfunctional.

True

The cell is the basic unit of life.

True

Vegetable oil is an unsaturated fat from multiple plant sources. Because it is unsaturated, it is composed of at least one pair of double-bonded carbons.

True

Whenever ATP is produced by a chemical reaction, some energy is lost into the surroundings as heat.

True

Your biology instructor has assigned you a lab exercise to test a hypothesis regarding the inheritance of stem length in pea plants. If your assignment is specifically to conduct a monohybrid cross for stem length from available genotypes growing in the lab, which of the following crosses should be performed?

Tt with Tt

The sex chromosomal combination for a human male is

XY

Refer to this diagram with common examples of substances and their pH. Our normal blood pH should be in a fairly narrow range. Imagine you sit down to eat a large meal with cola, tomato-based sauce, and a salad with many citrus fruit slices. Identify the one statement that does not apply as one of the likely outcomes of your meal.

Your blood and body fluids will likely become more basic, with a higher pH than the normal range.

The bond that builds amino acid monomers into protein polymers is

a covalent bond also known as a peptide bond.

If a carbohydrate polymer is limited to two monomer units, such as sucrose made from glucose and fructose, it is called

a disaccharide.

A phospholipid molecule has

a hydrophilic head that is attracted to water.

A change in a cell's DNA sequence is

a mutation.

An ion is an atom that has

a net negative or positive charge, with the number of electrons different from the number of protons.

The three major components in a nucleotide are

a nitrogen base, a five-carbon sugar, and a phosphate group.

Carbon and hydrogen make up many biologically important molecules. Carbon has an electronegativity of 2.55, whereas hydrogen has an electronegativity of 2.2. Based on the electronegativity difference between the atoms, the carbon and hydrogens shown here have just formed

a nonpolar covalent bond.

Using the genetic code shown here, predict what type of mutation has occurred in the hemoglobin sickle-cell anemia allele.Normal allele 5'-GGAAUGAAACAGGAACCC-3'Mutant allele 5'-GGAAUGAAACAGGUACCC-3'

a point mutation, Glu to Val

Which is not a lipid?

a starch

The four nitrogen bases found in RNA are

adenine, cytosine, guanine, and uracil.

Trees are able to transport water from the roots to the top branches because

adhesion bonds water molecules to the inside of the plant conducting tubes.

If you, like Mendel, grow plants in the lab, and cross short (tt) pea plants with short pea plants, the offspring will be

all short

The primary building block (monomer) of proteins is

an amino acid.

Which of the following would not be a "control" in an experimental procedure?

an experimental group

You perform an experiment in which you take 16 pots of strawberry plants and give half of them 1 gram of ammonium nitrate per liter of water and the other half just gets water. Each group is then split in half again, and exposed to either 8 or 16 hours of light each day. You monitor the height of the plants for four weeks. You observe that increasing ammonium nitrate and light both increase plant height. The leaf of a plant is

an organ

An enzyme is

an organic molecule that catalyzes a cellular reaction.

In pedigree charts, autosomal dominant disorders are expressed in heterozygotes. Therefore, the disorders are typically

appear in every generation.

The original three components of the cell theory are that all organisms

are made of one or more cells, the cell is the fundamental unit of life, and all cells come from preexisting cells.

Thinking about life's organizational hierarchy in a biological system, which of the following is the correct sequence from the smallest unit to the largest unit?

atom - molecule - organelle - cell - tissue

In an ionic bond,

atoms, having gained or lost electrons, attract one another with opposite charges.

During glycolysis molecules of glucose are

broken down by enzymes to form two molecules of pyruvate.

In eukaryotic cells, how can a single gene encode for more than one protein?

by removing different combinations of introns

Once ATP donates its phosphate to a coupled reaction it becomes ADP. The ADP

can be recharged in an endergonic reaction to form ATP.

You are in biology lab examining plant root cells. You can still see chromosome strands, as they are in compact bundles. You conclude the cells are undergoing cytokinesis because you also observe the formation of the

cell plate.

This diagram shows how DNA is packaged and folded with its associated protective and regulatory proteins. A part of a chromosome that attaches sister chromatids to each other is the

centromere.

An example (or examples) of potential energy is/are

chemical bonds and concentration gradients.

In an oxygen element, each oxygen atom contains eight electrons in its valence shell. The atoms will be

chemically stable.

An organelle found in plant cells and some members of the kingdom Protista but not in animal cells is a

chloroplast.

Homeostasis means that

conditions inside a cell or organism remain within a constant range.

Organisms that obtain energy and nutrients by eating either living or dead organisms are called

consumers.

Among enzymes required for DNA replication, ligases are needed to form ________ bonds between nucleotides to join DNA segments.

covalent

Within a single molecule of water, as shown, ________ bonds are formed between oxygen and hydrogen.

covalent

Which of the following may occur in meiosis but not in mitosis?

crossing-over

Gametes may carry different combinations of alleles because of

crossing-over and random alignment of chromosomes.

Cyanide and carbon monoxide block the final step in the electron transport chain. Consequently, ATP production in the mitochondria would

decrease, because electrons would not move through the electron transport chain and reduce oxygen.

In an experimental procedure, the researcher measures changes, such as cell growth rates, numbers of patients with a disease, etc. in response to factors manipulated at the beginning of the experiment. This measure of change in response to the initial conditions is the

dependent variable.

By ignoring a checkpoint in the cell cycle, a cancer cell may

divide before its DNA is completely replicated.

A major difference between prokaryotes and eukaryotes is that although prokaryotes

do not have a nucleus, eukaryotes have a nucleus in their cells.

A prokaryotic cell

does not have a nucleus.

Mendel observed that some genetic traits seemed to mask others in the pea plants. The masking trait is referred to as the

dominant trait.

The six carbons that form glucose in your food are effectively lost from the cell as CO2

during the oxidation of pyruvate to acetyl CoA, and in the Krebs cycle.

Phagocytosis of an infective bacterium by a white blood cell is a subset type of

endocytosis.

The process by which a sperm cell combines with an egg cell is

fertilization.

The three main biochemical pathways of cellular respiration are

glycolysis, Krebs cycle, and electron transport.

In an experimental procedure, the researcher has established multiple levels of a chemical, or amounts of light, or some other factor at the beginning of the experiment, in order to determine if and how much the biological system responds. The manipulated factor at varying levels is the

independent variable

In eukaryotic cells, transcription and replication occur during ________ of the cell cycle.

interphase

A base

is a chemical that absorbs hydrogen ions from a solution.

An acid

is a chemical that adds hydrogen ions to a solution.

The Calvin cycle

is a cyclic reactive pathway that produces three-carbon molecules from CO2.

If a cell has a greater concentration of solute than its environment, the cell

is hypertonic to the environment.

Which of Mendel's laws described the separation of two alleles during the formation of gametes?

law of segregation

Enzymes speed chemical reactions by

lowering the energy required to start a chemical reaction.

In the 1700s, a French scientist, Antoine Lavoisier, gained new experimental information by reacting a metal and an acid. His observation of the results seemed to show that much of the metal had been lost in the chemical reaction. Upon weighing the products, the total amounts of materials had not changed during the reaction. This research resulted in the law of conservation of mass. This law also applies to biology, because the materials we are made of are ________ that change forms, but aren't truly lost through biochemical reactions.

matter

In meiosis, chromosomes containing sister chromatids (not homologous chromosomes) align along the center of the cell during

metaphase II.

In animal, plant, fungal, and algal cells, the primary organelle that generates molecules of ATP is the

mitochondrion.

In an asexual life cycle, cells reproduce by

mitosis.

Which of these is not a required characteristic of life?

movement

Which is the correct sequence of steps in the scientific method?

observation - form hypothesis - design an experiment - collect data - analyze results

To be considered living, an organism must minimally consist of

one or more cells.

Gametes contain

one set of chromosomes.

A structure, such as a flower in plants, or a liver in animals, consisting of tissues organized to carry out a specific function is a(n)

organ.

Water has unique properties which include its strength as a solvent; its three environmental stages of solid, liquid, and gas; and its temperature regulation. These properties are due to polar covalent bonds between oxygen and hydrogen. The polar covalent bonds are a result of

oxygen being more electronegative and therefore attracting more electrons than hydrogen.

The "spent" electrons from electron transport in aerobic cellular respiration are transferred to

oxygen, thereby reducing it to form water.

The primary structural molecule composing a cell membrane is a(n)

phospholipid molecule.

Which of these organism(s) photosynthesizes?

plants, algae, and cyanobacteria

Plant growth and flowering are strongly controlled by root and stem signal chemicals. Which of the following cell connection transports these molecules between adjacent cells?

plasmodesmata

The hierarchy of life extends past individual organisms. Which of the following is the correct sequence, from least inclusive to most inclusive, following an individual organism?

population - community - ecosystem - biosphere

Organisms that make their own nutrients by capturing energy from nonliving resources (solar energy) are called

producers.

Meiosis is a process used for

production of gametes.

Apoptosis is the process of

programmed cell death.

The starting point of a gene on the DNA where the RNA polymerase binds is called the

promoter.

The mass number is defined as the total number of ________ of an atom.

protons and neutrons

The atomic number of an element is the number of

protons in the nucleus.

In a chemical equation, which components of a chemical reaction are found on the left side of the arrows?

reactants

At chemical equilibrium

reaction rates are in balance.

A person who has just experienced a painful sunburn has a large number of cells undergoing mitosis for the purpose of

repairing and replacing the damaged cells, in the healing process of the skin.

A structure found in cells of all three domains, prokaryotes and eukaryotes, is the

ribosome.

Before biologists discovered the role of DNA and chromosomes, Gregor Mendel, a scientific researcher, studied the genetics of pea plants related to flower colors, pea colors, pea pod shapes, and other features of the plant. He numerically modeled the results he observed and published results, which eventually led to our basic understanding of how biological traits are passed to new generations of organisms. His work, however, was largely rejected for over 30 years, partly for minor record-keeping errors, and partly for the new approach of defining reproduction of organisms in terms of numerical probabilities. This demonstrates that

scientific evidence is harder to accept because of cultural biases and misunderstandings on the topic.

In a covalent bond, atoms

share electrons.

After replication, in eukaryotic cells, both the original and its replicated copy chromosome are each called a

sister chromatid.

Thinking about taxonomy, the basic unit of naming, that includes members with the ability to reproduce with each other, is

species

Genotype refers to

the combination of alleles in an individual.

Oxidation and reduction reactions are typically linked within a cell. They are part of most matter and energy transformations necessary for vital life functions.

the loss of electrons from a molecule.

In humans, alleles for each gene are inherited from

the mother and the father (one allele from each parent).

Algal phytoplankton are single-celled water organisms that perform photosynthesis like plants. In a lake, summer growth of phytoplankton can change the water pH from pH 7.2 to 6.2. This change indicates all of the following except

the water at pH 6.2 has twice the hydrogen (H+) concentration than before the phytoplankton growth.

A diploid cell only has two copies of most genes, but can make hundreds of copies of a protein from those genes per second because

transcription can repeat and make multiple mRNA copies of genes, and multiple ribosomes can translate the same mRNA.

Oxidation and reduction reactions are typically linked within a cell. They are part of most matter and energy transformations necessary for vital life functions. Oxidation-reduction reactions

transfer electrons from one molecule to another.

The process used by cells to convert the mRNA "message" into a sequence of amino acids is

translation.

The first energy shell of an atom has one orbital. Therefore, it can contain a maximum of ________ electron(s).

two

This diagram summarizes energy transfers and molecule exchanges among plants and animals, as you will later learn we call producers and consumers. The molecular reactants for photosynthesis are

water and carbon dioxide.

Examine this image, showing an electron transport chain in photosynthesis. The electrons flowing through the electron transport chains in photosynthesis come from ________ and end up being carried by ________.

water; NADPH

Competitive inhibition of enzymes occurs

when a substance other than the substrate binds at the active site of an enzyme.

If you cross two pea plants, one with green peas and the other with yellow peas, you find all of the offspring have yellow peas. You conclude

yellow is dominant over green.