Bio 120 Final Exam Review Flashcards

Flashcards for Bio 120 Final Exam Review covering Meiosis, Mendel's Genetics, DNA Synthesis, Gene Function, Transcription, Translation, and General Biochemistry and Cell Biology.

What is a karyotype?

The number and appearance of chromosomes in the nucleus of a eukaryotic cell.

What does haploid mean?

Having a single set of unpaired chromosomes.

What does diploid mean?

Containing two complete sets of chromosomes, one from each parent.

What does tetraploid mean?

Having four sets of chromosomes.

What does polyploidy mean?

Containing more than two paired (homologous) sets of chromosomes.

What are autosomes?

Any chromosome that is not a sex chromosome.

What are gametes?

A mature haploid male or female germ cell that is able to unite with another of the opposite sex in sexual reproduction to form a zygote.

What are homologous chromosomes?

Chromosomes that have the same genes in the same positions and structural features.

What are sister chromatids?

Two identical copies of a single replicated chromosome that are connected by a centromere.

What is a loci?

Specific location or position of a gene on a chromosome.

What is a phenotype?

The observable physical or biochemical characteristics of an organism, as determined by both genetic makeup and environmental influences.

What is a genotype?

The genetic constitution of an individual organism.

What does it mean that DNA synthesis is semiconservative?

DNA replication in which each new molecule consists of one original and one newly synthesized strand.

What is topoisomerase?

Enzymes that help to relieve the strain on DNA when unwinding by causing breaks and then resealing the DNA.

What is primase?

Synthesizes short RNA sequences called primers to provide a 3'-OH group for DNA polymerase to initiate DNA synthesis.

What is helicase?

An enzyme that separates double-stranded DNA into single strands allowing each strand to be copied.

What is ligase?

An enzyme that catalyzes the joining of Okazaki fragments during DNA replication and connects new DNA fragments to existing DNA.

What is RNA polymerase?

An enzyme that is responsible for making RNA from a DNA template.

How do nitrogenous bases bind?

In RNA, adenine binds to uracil, while guanine binds to cytosine. In DNA, adenine binds to thymine, guanine binds to cytosine.

What does it mean that DNA is always written 5’ to 3’?

It refers to the convention of numbering the carbon atoms in a nucleotide's deoxyribose or ribose sugar ring. DNA is synthesized by adding new nucleotides to the 3' end of the growing strand.

What is the central dogma of biology?

DNA -> mRNA -> tRNA -> protein.

What is transcription?

The synthesis of RNA from a DNA template where the code in the DNA is converted into a complementary RNA code.

What is translation?

The synthesis of a polypeptide using the genetic information encoded in an mRNA molecule. There is a change in the language from nucleotides to amino acids.

What are introns?

Noncoding segments of nucleic acid that lie between coding sequences and are removed by RNA splicing.

What are exons?

A coding region of eukaryotic genes that are expressed/translated into proteins.

What is the wobble effect?

Multiple codons can code for the same amino acid.

What are snRNPs (small nuclear ribonucleoproteins)?

Enzymes that catalyze the removal of introns from pre-mRNA.

What is the sigma factor?

A protein needed for initiation of transcription in bacteria. It enables specific binding of RNA polymerase to gene promoters.

What is aminoacyl-tRNA synthetase?

An enzyme that catalyzes the attachment of a tRNA to its specific amino acid.

What is splicing mRNA transcripts?

The process of changing the pre-mRNA to mature mRNA by excising introns and joining exons.

What are the APE sites of ribosomes during translation?

The A site binds to the tRNA carrying the next amino acid to be added to the chain. The P site holds the tRNA carrying the growing polypeptide chain. The E site is the exit site, where discharged tRNAs leave the ribosome.

What are covalent bonds?

Chemical bonds characterized by the sharing of one or more pairs of electrons between atoms.

What are ionic bonds?

Chemical bond resulting from the attraction between oppositely charged ions.

What are hydrogen bonds?

A weak chemical bond formed by the attraction of a slightly positive hydrogen atom to a slightly negative atom.

What are isotopes?

forms or varieties of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei

What is the octet rule?

States that in chemical bonds, atoms tend to gain, lose, or share electrons in order to achieve a full outer electron shell containing eight electrons.

What is dehydration synthesis or condensation reaction?

Reaction where molecules are connected by the removal of a water molecule .

What is the primary structure of a protein?

The sequence of amino acids in a polypeptide chain.

What is the secondary structure of a protein?

Regions of repetitive coiling or folding of the polypeptide backbone of a protein due to hydrogen bonding between constituents of the backbone (not the side chains).

What is the tertiary structure of a protein?

The overall shape of a protein molecule due to interactions of amino acid side chains, including hydrophobic interactions, ionic bonds, hydrogen bonds, and disulfide bridges.

What is the quaternary structure of a protein?

The particular shape of a complex, aggregate protein, defined by the characteristic three-dimensional arrangement of its constituent subunits, each a polypeptide.

What is an active site?

A region on an enzyme that binds to a protein or other substance during a reaction.

What is the role of kinase?

Adds phosphate groups to other proteins.

What is catabolism?

Metabolic pathways that break down molecules, releasing energy.

What is anabolism?

Metabolic pathways that construct molecules, requiring energy.

What is oxidation?

Loss of electrons from a substance during a redox reaction.

What is reduction?

Addition of electrons to a substance during a redox reaction.

What is metabolism?

The totality of an organism's chemical reactions, consisting of catabolic and anabolic pathways.

What is cell respiration?

A set of metabolic reactions and processes that take place in the cells of organisms to convert chemical energy from oxygen molecules or nutrients into adenosine triphosphate (ATP), and then release waste products

What does it mean for a phospholipid to be amphipathic?

Having both a hydrophilic region and a hydrophobic region.

What is a centromere?

The structure that joins sister chromatids.

What is a kinetochore?

A structure of proteins attached to the centromere that links each sister chromatid to the mitotic spindle.

What is phagocytosis?

A type of endocytosis in which large particulate substances or small organisms are taken up by a cell.

What do viruses do?

A way that viruses replicate, by invading host cells and using their transcription/translation machinery to replicate more viruses.

What is substrate-level phosphorylation?

The enzyme-catalyzed formation of ATP by direct transfer of a phosphate group to ADP from an intermediate substrate in catabolism.

What is oxidative phosphorylation?

The production of ATP using energy derived from the redox reactions of an electron transport chain.

What is aerobic respiration?

Respiration that requires oxygen.

What is anaerobic respiration?

Respiration that does not require oxygen.

What is chromatin?

Complex of DNA and proteins that makes up eukaryotic chromosomes.

What are histones?

A small protein with a high proportion of positively charged amino acids that binds to the negatively charged DNA and plays a key role in chromatin structure.

What is a nonsense mutation?

A stop codon mutation that results in a premature termination of protein translation.

What is a missense mutation?

A point mutation in which a single nucleotide change results in a codon that codes for a different amino acid.

What is a frameshift mutation?

A mutation occurring when the number of nucleotides inserted or deleted is not a multiple of three, resulting in the improper grouping of the subsequent nucleotides into codons.

What is the net input of glycolysis?

1 moleucle of glucose (the starting substrate), 2 ATP

What is the net output of glycolysis?

2 pyruvate, 2 NADH, 2 ATP

What is the net input of the Krebs cycle?

2 Acetyl-CoA, 6 NAD+, 2 FAD, 2 ADP (or GDP) + Pi, 2 H2O

net output of Krebs cycle?

6 NADH, 2 FADH2, 2 ATP (or GTP), 4 CO2(as waste)

net input of ETC?

10 NADH, 2 FADH2, O2, ADP + Pi

net output of ETC?

H2O, 30-38 ATP