词汇如下：

　　Recessive(隐性)

　　Refers to an allele that cannot control the phenotype unless it is the only kind of allele present, as in a homozygote or hemizygote. Also refers to the trait or phenotype produced when only a recessive allele is present. The opposite of recessive is dominant.

　　reproductive isolation(生殖隔离)

　　The inability of individuals within a species to create offspring with members of any other species. The mark of a species is its reproductive isolation from all other species.

　　respiratory system(呼吸系统)

　　The organ system responsible for the intake of oxygen and diffusion of that gas into the blood and the elimination of carbon dioxide from the body. Important structures of the system are the pharynx, larynx, trachea, bronchi, bronchioles, and lungs. Alveoli in the lungs are the location of gas exchange with the blood. The movement of the muscular diaphragm allows the lungs to inhale and exhale.

　　ribonucleic acid (RNA/核糖核酸)

　　One type of nucleic acid polymer. RNA nucleotides’ sugars contain one more oxygen atom than DNA nucleotides’ sugars. RNA nucleotides can have the nitrogenous bases adenine, cytosine, guanine, and uracil.

　　Ribosome(核糖体)

　　Organelle responsible for protein synthesis. Ribosomes are located in cytoplasm or endoplasmic reticulum.

　　Root(根)

　　The part of a plant beneath the soil; responsible for collecting water and minerals from the soil, storing nutrients, and securing the plant to the ground. Can be fibrous or a taproot.

　　root hair(根须)

　　An outgrowth of a plant root that provides an increased surface area for the absorption of water and dissolved minerals from the soil.

　　Runner(匍行)

　　Slender horizontal stem that can form new plants via specialized nodes.

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