21 造成耳蝸（cochlea）內hair cell去極化的機轉為何？

 鉀與鈣離子由endolymph流入hair cell 鉀與鈣離子由perilymph流入hair cell

 鈉與鈣離子由endolymph流入hair cell 鈉與鈣離子由perilymph流入hair cell

A

MAGIC IS INSIDE! THE ENDOLYMPH : HAIR CELL

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22 在視覺神經傳導路徑中，最早產生動作電位（action potential）的細胞為何？

Bipolar cell Ganglion cell Horizontal cell Photoreceptor cell

B

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24 一位30歲健康男性因車禍嚴重陰囊外傷，而切除兩側睪丸。切除兩側睪丸後，並未予以補充睪酮（testosterone）。該患者所發生之生理變化，下列何者正確？

 身高會變得更高一些 聲音會變得像青春期之前般的童音

陰部毛髮會逐漸變得稀疏 陰莖勃起功能會消失

C

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25 下列那一種腦下腺激素負責引起排卵？

泌乳素（prolactin） 黃體促素（luteinizing hormone）

催產素（oxytocin） 甲促素（thyrotropin）

B

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27 下列何者不會出現於phenylketonuria病患的尿液中？

Phenylalanine Phenylpyruvate

Para-hydroxyphenylpyruvate Phenylacetate

C

The enzyme phenylalanine hydroxylase normally converts the amino acid phenylalanine into the amino acid tyrosine.

If this reaction does not take place, phenylalanine accumulates and tyrosine is deficient.

Excessive phenylalanine can be metabolized into phenylketones through the minor route, a transaminasepathway with glutamate.

PHENY ALA ACE PYRUVATE!!!!!!!!!!!!!!

Metabolites include phenylacetate, phenylpyruvate and phenethylamine.^[11] Elevated levels of phenylalanine in the blood and detection of phenylketones in the urine is diagnostic.

Phenylalanine is a large, neutral amino acid (LNAA). LNAAs compete for transport across the blood-brain barrier (BBB) via the large neutral amino acid transporter (LNAAT). If phenylalanine is in excess in the blood, it will saturate the transporter. Excessive levels of phenylalanine tend to decrease the levels of other LNAAs in the brain. However, as these amino acids are necessary for protein and neurotransmitter synthesis, phenylalanine buildup hinders the development of the brain, causing mental retardation