问题 问答题 简答题

试述上下颌各牙齿及其牙龈和牙周膜的神经支配情况。

答案

参考答案:

上下颌各牙齿及牙龈、牙周膜的神经支配情况如下:

(1)上颌1~3的牙体、牙周膜及颊侧牙龈由上牙槽前神经支配,腭侧牙龈由切牙孔神经支配。在3的腭侧切牙孔神经与腭前神经相汇合。

(2)上颌4~5及6的近中颊根及颊侧牙龈和牙周膜由上牙槽中神经支配,腭侧牙龈由腭前神经支配。

(3)上颌6的腭侧根及远中颊根和7~8的牙体、牙周膜和颊侧牙龈由上牙槽后神经支配,腭侧牙龈由腭前神经支配。

(4)下颌1~8的牙体、牙周膜由下牙槽神经支配,舌侧牙龈由舌神经支配,1~4的颊侧牙龈由颏神经支配,5~8的颊侧牙龈由颊神经支配。下牙槽神经、舌神经及颏神经在中线处与对侧的同名神经相交叉吻合。

阅读理解

Brownie and Spotty were neighbor dogs. They loved each other and played together so often that they had worn a path through the grass of the field between their houses.

One evening, Brownie’s family noticed that their dog hadn’t returned home. They went looking for him, but with no success. Brownie didn’t show up the next day, and by the next week he was still missing.

Curiously, Spotty showed up at Brownie’s house alone. He barked loudly. But busy with their own lives, Brownie’s family just ignored (忽略) their neighbor’s nervous little dog.

Finally, one morning Spotty refused to take “no” for an answer. He followed Ted, Brownie’s owner, everywhere he went. He barked, then rushed towards a nearby empty lot and back, as if to say, “ Follow me!”

Finally, Ted followed the dog across the empty lot. The dog led the man to a tree a half-mile from the house. There Ted found Brownie alive. One of his legs was crushed (夹住) in a trap. Ted wished he had taken Spotty’s earlier appeals (求助) seriously.

Then Ted noticed something amazing. In a circle around the injured dog, he saw a lot of dog food. They were the remains of lots of meals.

Spotty had been visiting Brownie every day. He had stayed with Brownie to protect him, snuggling(依偎) with him at night to keep him warm and nuzzling(用鼻子爱抚) him to keep his spirits up.

小题1:What can we learn from the first three paragraphs?

A.Brownie and Spotty didn’t like their owners.

B.Brownie was missing for three days.

C.Brownie’s family didn’t love him.

D.Spotty probably knew where Brownie was.小题2:According to the story, which of the following is TRUE?

A.Spotty barked loudly at Ted because he was scared.

B.Ted followed Spotty because Spotty asked him to.

C.Spotty succeeded in escaping from the trap.

D.Brownie had nothing to eat that whole week.小题3:The underlined phrase “keep his spirits up” in the last paragraph probably means______.

A.feed him

B.praise him

C.comfort him

D.protect him小题4:What does the story aim to tell us?

A.Dog is man’s best friend.

B.Even dogs can have strong friendship.

C.Dogs are one of the cleverest animals.

D.Dogs have a special way to look for help.

单项选择题