chromosomes

a cell membrane

a nucleus

ribosomes

A silent mutation results in the insertion of a different amino acid

A base is inserted into one strand of the DNA

A deletion of a cytosine base occurs

A substitution occurs with the adenine base

competition

commensalism

predation

parasitism

Sunlight absorption

Seed dispersal

Photosynthesis

Disease resistance

The ecosystem will become unstable because predators will have fewer prey, the birds will have fewer nesting sites, and the area downriver will become vulnerable to flooding without the burrows to aerate the soil and provide drainage for monsoon rains.

The ecosystem will become more stable because the pika will be replaced by other species of small mammals that can fill the niche, bird species will adapt to nesting aboveground, and the soils will become compacted without the burrows.

The ecosystem will become more stable because the pika will no longer be there to eat the grasses, the birds will migrate to other ecosystems during nesting season, and the soils will be able to absorb more of the monsoon rains without the pika burrows.

The ecosystem will become unstable because the predators will migrate to nearby ecosystems, the birds will nest in nearby trees, and the soils will be aerated by other small mammals.

synthesizes new molecules

maintains genetic homeostasis

duplicates the DNA

completes cell division

An enzyme works equally well in bacteria that are adapted to high temperatures and in eukaryotic cells such as human cells

An enzyme functions best under specific temperature conditions

An enzyme must be composed of multiple polypeptides, or subunits, to be active.

An enzyme’s rate of activity increases with time until it becomes inactive.

a decrease in the flow of blood to vital organs

a decrease in the amount of oxygen being transported to tissues

an increase in the threat of diseases caused by microorganisms and viruses

an increase in the risk of high blood pressure

Allele frequencies suddenly change

Relative genotypic frequencies reach a constant state

Intermediate phenotypes increase in the species

Gene flow occurs between populations

The roots from plants help stabilize the sediment, keeping it in place

The concentration of salt becomes so high that all plant life is destroyed

The soil becomes so fertile that eel grass is replaced by other plant species

The rotting remains of plants add to the fertility of the soil

the sequence of nucleotides in DNA

the location of sugar groups in DNA

the number of nitrogenous bases in DNA

the molecules attached to the phosphate in DNA

Environmental conditions for speciation were most favorable for reptiles during the Permian period

A great extinction occurred during the Jurassic period

Competition for food and shelter among reptile species was very low during the Triassic period

Reptiles adapted to a terrestrial environment during the Cretaceous period

Endocrine and digestive systems

Circulatory and nervous systems

Immune and lymphatic systems

Digestive and nervous systems

Less carbon dioxide gas would be contained in the ocean because increasing precipitation would dilute the carbon entering the ocean

Less carbon dioxide would be dissolved in the ocean because increasing atmospheric temperatures would cause ocean temperatures to increase

Less atmospheric carbon dioxide would be available to phytoplankton

Dissolved carbon dioxide gas in the ocean would increase because surface winds would cause a deeper circulation pattern, making more room for the gas

Nucleic acid

Chlorophyll

Wax

Glucose

fruit flies and frogs can be made to develop some of the same physical traits

the replication of genetic material can occur at any temperature

heat can cause mutations in the DNA sequences of organisms

similar nucleotides are present in both fruit-fly and frog DNA

Each cell has multiple copies of DNA that are affected in different ways by the environment to change the function of the cell at regular intervals

Each cell type has only one chromosome containing the DNA needed for that cell type

Each cell type contains only the active parts of the DNA needed for that cell type

Each cell has an identical copy of DNA with enzymes controlling the expression of specific genes, leading to a variety of cells

the body experiences dehydration

body temperature drops

blood glucose levels are stable

the urinary tract is infected