Senior Comps

Exergonic reactions

Products have less free energy than reactants.

Substrate in an enzyme-mediated reaction

The reactant on which an enzyme acts.

Location of the Krebs (citric acid) cycle

Mitochondrial matrix.

Electromagnetic energy

Travels as waves and occurs in discrete packets called photons.

Action spectrum of photosynthesis

Wavelengths of light utilized in photosynthesis.

Cycles in cellular respiration and photosynthesis

Cellular respiration uses the Krebs cycle; photosynthesis uses the Calvin cycle.

Germ layer that forms skeleton and circulatory system

Mesoderm.

A substance that completely dissolves in water

May be an ionic or polar compound.

Rough endoplasmic reticulum surface

Covered with ribosomes.

Common feature of facilitated diffusion and active transport

Both use membrane transport proteins.

Processes requiring membrane carrier proteins

Active transport and facilitated diffusion.

Hydrolysis of triglycerides

Breaks triglycerides into glycerol and fatty acids.

Four most common elements in living things

Carbon, hydrogen, oxygen, and nitrogen (CHON).

Chemical bond

Force of attraction between atoms.

Separation of sister chromatids

Occurs in mitosis and meiosis II.

Interphase and mitosis

Interphase is not a formal stage of mitosis.

Stratified squamous epithelium

Epithelial tissue with several layers of flat cells.

Muscle type attached to bones

Skeletal muscle.

Plant water and sugar transport

Xylem transports water; phloem transports sugars.

Relative size of egg, zygote, morula, and blastula

All are approximately the same overall size during early cleavage.

Phenotype

Observable expression of a trait.

GATTACA changing to CATTACA

Point mutation by base substitution.

Plasma

Liquid portion of blood.

Hemolymph

Circulatory fluid found in arthropods.

Countercurrent flow in the human kidney

Occurs in the loop of Henle.

Genotype of a Mendelian F1 hybrid

Heterozygous.

Daughters of a colorblind woman and a man with normal color vision

0% colorblind daughters, assuming X-linked recessive inheritance; all daughters are carriers.

Locus

Physical position of a gene on a chromosome.

Expression of regulatory genes in operons

Typically constitutive (continuous).

RNA transcribed from template DNA AATGCACGT

UUACGUGCA.

When the trp operon is off

When the tryptophan-bound repressor binds the operator.

Contents of synaptic vesicles

Neurotransmitters.

Elevated intraocular pressure from aqueous humor

Can cause glaucoma.

Sarcomere

Standard contractile unit of skeletal muscle.

Cephalization

Evolutionary concentration of nervous-system regulation in the head.

Two senses that detect similar stimulus types

Touch and hearing; both detect mechanical stimuli.

Ion released from sarcoplasmic reticulum for contraction

Calcium ions (Ca2+).

Enzymes for protein digestion

Pepsin, trypsin, and peptidases.

Antibody-specific immunological memory

Feature of the humoral immune response.

Invaginated respiratory structures

Lungs and tracheal tubes.

Biological species concept

Members of the same species can interbreed and produce fertile offspring.

Common descent and humans versus chimpanzees

Humans did not descend from modern chimpanzees; they share a common ancestor.

Principal mechanism of evolution according to Darwin

Natural selection.

Role of individuals in natural selection

Survive and reproduce.

Traits that can undergo natural selection

Heritable traits.

Taxonomic ranks from largest to smallest

Kingdom, phylum, class, order, family, genus.

Paraphyletic group

Contains a common ancestor and some, but not all, of its descendants.

Phylogeny

Evolutionary history of a group of organisms.

Basic fungal body plan

Mycelium and spore-producing structures.

Closest major eukaryotic group to animals

Fungi.

Carbon returned to atmosphere in carbon cycle

Fossil fuel combustion and plant/animal respiration release carbon dioxide.

Gross primary production (GPP)

Total sunlight energy converted to chemical energy by photosynthesis.

Mycorrhizal association

Mutualism: fungi supply minerals to plants; plants supply carbohydrates to fungi.

Energy flow through trophic levels

Producers → primary consumers → secondary consumers.

Carrying capacity

Maximum population size an environment can support.

Phylum of sea urchins

Echinodermata.

Adaptive advantage of seeds over spores

Seeds contain a protected embryonic plant and stored resources; spores generally consist of a single cell.

Floral structure not part of the pistil

Filament (part of the stamen).

Plant cuticle

Nonliving waxy deposit that reduces water loss.

Oldest terrestrial fungal phylum in traditional classification

Zygomycota (as framed by the practice exam).

Lysogenic bacteriophage

Bacterial virus whose genome can be maintained long-term in a host, often integrated into its chromosome.

Koch's postulates

Guidelines for determining which microorganism causes a particular disease.

Bacterial structures that resist phagocytosis

Capsules.

Gram-positive aerotolerant fermenting bacteria

Lactic acid bacteria.

Resolving power in microscopy

Ability to distinguish closely spaced objects as separate.

Components of Gram-negative cell envelope

Peptidoglycan, Braun lipoprotein, and lipopolysaccharide.

Lysogeny

Long-term maintenance of bacteriophage genetic material in a bacterial host without immediate lysis.

Feature shared by all viruses

Contain nucleic acid (DNA or RNA).

Zygospores

Sexual spores produced by zygomycete fungi.

Antiseptics versus disinfectants

Antiseptics are formulated for living surfaces.

Peptidoglycan in Gram-negative bacteria

Present as a thin layer.

Viroids

Short infectious single-stranded RNA molecules.

Endotoxin associations

Lipopolysaccharide (LPS) of Gram-negative bacteria, including E. coli and Salmonella; can cause severe illness.

Why viral infections are difficult to treat selectively

Viruses rely on host-cell metabolic machinery, limiting virus-specific drug targets.

Cellular structures containing nucleic acids

Chromosomes, ribosomes, and plasmids.

Component unique to Gram-negative outer membrane

Lipopolysaccharide (LPS).

Peptide interbridges in bacterial cell walls

Characteristic of Gram-positive peptidoglycan.

Spirochetes

Flexible helical bacteria.

Functions of bacterial capsules

Help evade phagocytosis, block some phages, and retain water to prevent desiccation.

Bacterial plasmids

Usually nonessential extrachromosomal DNA that replicates independently and may carry survival or resistance genes.

Purpose of X-chromosome inactivation

Dosage compensation.

Messenger RNA (mRNA)

RNA template used for polypeptide synthesis.

Lac operon induction conditions

Lactose present and glucose low favor expression of lac structural genes.

Final step of gene expression in the central dogma

Translation.

Enzyme that synthesizes RNA from a DNA template

RNA polymerase.

DNA polymerase I proofreading

Uses exonuclease activity to remove incorrectly incorporated nucleotides.

DNA molecules at metaphase II if haploid number is n

2n DNA molecules per cell.

DNA with 23% adenine and 35% thymine

Single-stranded DNA; the exam identifies viral single-stranded DNA.

Transposons

DNA sequences capable of moving to new positions in the genome.

Species most closely related by DNA reannealing

Species 2, with the highest DNA hybridization value (6.1%).

Product rule in probability

Multiply probabilities of independent events occurring together.

OriC in Escherichia coli

Origin where chromosomal DNA replication begins.

Eight unreplicated chromosomes in two groups of four at opposite poles (n=4)

Late anaphase of mitosis.

Parental F2 phenotypes in the fruit fly three-gene testcross

7,500 flies (3,715 + 3,785).

Middle gene in the L, R, M fruit fly linkage map

L gene.

Genotypes of the original fruit fly parental stocks

Homozygous at all three loci.

Mendelian principle of segregation

The two alleles of a gene separate during gamete formation; demonstrated by monohybrid crosses.

Effect of allolactose binding the lac repressor

Repressor releases the operator, allowing transcription of lactose-metabolism genes.

RNA polymerase holoenzyme

Recognizes the DNA promoter region to initiate transcription.

Meiotic stage when replicated chromosomes align individually on the spindle

Metaphase II.