In plants and bacteria, phenylalanine and tyrosine are synthesized from chorismate in pathways much more complex than the tryptophan pathway.

Which one of the following amino acids in the protein does NOT have<br/>its genetic codon? ( ) A: Methionine B: Hydroxyproline C: Tryptophan D: Glutamine

According to the first paragraph, gelatin________. A: is a protein that can be obtained from animals B: is harmful to human bodies C: should not be made into a dessert D: is lacking in tryptophan and arginine

The main purpose of semi-solid medium is (). A: Check the motility of bacteria B: Check the ability of bacteria to metabolize glucose to produce acid and gas C: Check the ability of bacteria to metabolize tryptophan to produce indole D: None of the above

在哺乳动物的核基因中，UGA是终止密码，但在线粒体DNA中，却是（）的密码子。 A: Arginine （精氨酸） B: Leucine （亮氨酸） C: Tryptophan （色氨酸） D: Serine （丝氨酸）

8.在哺乳动物的通用遗传密码中,UGA是终止密码,但在线粒体遗传密码中,却是()的密码子 A: Arginine(精氨酸) B: Leucine(亮氨酸) C: Tryptophan(色氨酸) D: Serine(丝氨酸)

在哺乳动物的核基因中，有三个终止密码，但终止密码UGA在线粒体的mRNA中，却是( ) 的密码子。[br][/br][br][/br][br][/br] A: Arginine (精氨酸) B: Leucine (亮氨酸) C: Tryptophan (色氨酸) D: Serine (丝氨酸)

在哺乳动物的核基因中,有三个终止密码,但终止密码UGA在线粒体的mRNA中,却是 A: 精氨酸(Arginine)的密码子 B: 亮氨酸(Leucine)的密码子 C: 色氨酸(Tryptophan)的密码子 D: 丝氨酸(Serine)的密码子 E: 起始密码的密码子