Transcript 基础医学英语Unit 6

Unit 6
The Digestive System
Word Formation
rect/o- 直肠
( rectum )
an/o- 肛门
( anus )
saliv/o- 唾液
( saliva )
de- 脱离, 分离 ( decompose, decontamination )
dis- 分开, 分离 (disassemble )
peptid/o- 肽 ( peptide , polypeptide)
muc/o- 黏液
( mucosa)
-gen 原, 发生物
( pepsinogen, glycogen )
hydr/o- 水
( hydrolyze, hydrolysis )
gastr/o- 胃
( gastrin )
-in
…素, …剂
( gastrin )
duoden/o- 十二,十二指肠
jejun/o- 空, 空肠
ile/o- 回肠
fec/o- 粪便
carbo- 碳
( duodenum )
( jejunum )
( ileum )
( defecation, feces )
( carbohydrate )
-ate …酸盐
tox/o- 毒，毒素
( carbonate, bicarbonate )
( detoxification )
syn- 连, 合, 联, 共
( syndrome, synthesize ）
ex(o)- 外， 在外
( excretion )
Group Discussion
1. Can you name the organs of digestive system in
English ?
2. Talk about common disorders in digestive system.
Clinical and pathological conditions
appendicitis----inflammation of the appendix
cholecystitis---- inflammation of the gallbladder
colitis----inflammation of the colon
enteritis----inflammation of the small intestine
gastroenteritis----an infection that causes
vomiting and diarrhea.
gastritis----inflammation of the stomach
hepatitis----inflammation of the liver
pancreatitis----inflammation of the pancreas
parotitis----inflammation of the parotid glands
heartburn----when the contents of the stomach
back up the esophagus.
ulcer---- a hole in the mucous membrane lining
the stomach or duodenum.
Introduction to Digestive system
We need food to fuel our bodies for energy, growth and
repair. The digestive system converts the foods we eat
into their simplest forms, like glucose (sugars), amino
acids (that make up protein) or fatty acids (that make
up fats). The broken down food is then absorbed into
the bloodstream from the small intestine and the
nutrients carried to each cell in the body.
The digestive tract begins at the mouth and ends
at the anus. It can be thought of as a long, muscular
tube, over 10 metres long, with digestive organs
attached along the way.
The mouth and esophagus
Digestion begins in the mouth. The food is ground up
by the teeth and moistened with saliva to make it easy
to swallow. Saliva also has a special chemical, called
an enzyme, which starts breaking down carbohydrates
into sugars. Once swallowed, muscular contractions
of the esophagus massage the ball of food down into
the stomach.
The stomach
The food passes through a sphincter or small muscle
ring into the stomach, where it is mixed with gastric
juices. The stomach is a muscular bag and it churns
the food to help break it down mechanically. The
food is then squeezed through a second sphincter
into the first part of the small intestine, called
the duodenum.
The small intestine
Once in the duodenum (small intestine), the food is
mixed with more digestive enzymes from the pancreas
and bile from the liver.
Pancreas
The pancreas is one of the largest glands in the human
body. As well as digestive juices, it secretes a hormone
called insulin. Insulin helps to regulate the amount of
sugar in the blood. Diabetes is a condition caused by
problems with insulin production.
Liver
The liver has a number of different roles in the body,
including:
Breaking down fats, using bile stored in the gallbladder
Processing proteins and carbohydrates
Filtering impurities and toxins.
Absorption happens in the small intestine
The food is squeezed into the lower parts of the small
intestine, called the jejunum and the ileum. Nutrients
are absorbed from the ileum, which is lined with millions
of finger-like projections called villi(绒毛). Each villus is
connected to a mesh of capillaries.This is how nutrients
pass into the bloodstream.
The large intestine
Once all the nutrients have been absorbed, the waste
is moved into the large intestine, or bowel. Water is
removed and the waste (feces) is stored in the rectum.
It can then be passed out of the body through the anus.
Things to remember
Food is broken down by the digestive system to
give energy to every cell in the body. The digestive
tract starts at the mouth and ends at the anus.
齿龈
悬雍垂
腭扁桃体
乳头状突起
磨牙
前磨牙
犬牙/尖牙
切牙/门牙
Palate
The palate is the roof of the oral cavity. It separates
the oral cavity from the nasal cavity. The anterior
portion, the hard palate, is supported by bone. The
posterior portion, the soft palate, is skeletal muscle
and connective tissue. Posteriorly, the soft palate
ends in a projection called the uvula. During
swallowing, the soft palate and uvula move upward
to direct food away from the nasal cavity and into
the oropharynx.
The pancreas is an elongated gland that is below
the stomach. It produces pancreatic juice that
contains digestive enzymes. The pancreas also
secrets insulin into the blood. Insulin is needed
to allow glucose or sugar from food to get into
the bloodstream. People who cannot produce
insulin are diabetics.
The largest gland in the body is the liver.
It is on the right side of the body underneath
the ribs. It weighs about three pounds and is
eight inches long. The liver stores a form of
glucose called glycogen.
Vitamin A is manufactured in the liver. Bile
which is needed to breakdown fat, is made
in the liver.This organ is also where alcohol,
drugs, bacteria and old blood cells are broken
down and removed from the body. Damage to
the liver can be serious because this organ is
extremely necessary to life.
The gallbladder is a small sac on the underside
of the right lobe of the liver. It stores bile that
is made by the liver. Bile travels from the liver
through the hepatic ducts to the gallbladder.
It holds about two ounces of bile. Bile is needed
to breakdown the fat that is in food.
Understanding the Text
Para.1
Question:
1.What are the organs that do not exactly belong to the
digestive system ?
Para.2
Question:
2.What is the function of mastication ?
Para.3
Question:
3.What is the function of saliva ?
Salivary gland
A gland that secretes saliva, especially any of three pairs
of large glands, the parotid(1), submandibular(2), and
sublingual(3), whose secretions enter the mouth and
mingle in saliva.
Function
 Saliva keeps the mouth and other parts of the digestive
system moist.
 Saliva also helps break down carbohydrates (with
salivary amylase, formerly known as ptyalin) and
lubricates the passage of food down from the
oropharynx to the stomach.
 Saliva also has elements that help to neutralise the acid
responsible for tooth decay; this is called a buffer.
 The antibacterial properties within saliva help to
sustain a neutral balance and prevent the development
of germs.
Para.4
Questions:
4.What is the function of esophagus ?
5.What is GERD?
Gastroesophageal reflux disease (GERD胃食管反流病) is
a gastric disorder which causes stomach acids to back up
into the esophagus, the tube leading from the mouth to
the stomach. This action causes pain, which is often called
heartburn. GERD can disrupt sleep and make eating
difficult. It can lead to respiratory infections, ulcers, and
even cancer.
Para.5
Questions:
6.What are the components of the stomach ?Can you say
something about its functions ?
Para.6-7
Question:
7.What are the functions of the fundus ?
Difficult Points
hydrochloric acid---盐酸
untwist--- vt. to loose 解开(缠绕的东西), 朝反方向扭开
e.g. 1) untwist a knot 解开一个结
2) untwisting the complex three-dimensional
protein chains
分解复杂的具有三维结构的蛋白链(p91)
denaturation of proteins
----the changes in the physical and physiological
properties of a protein that are brought about by heat,
X-rays, or chemicals. These changes include loss of
activity (in the case of enzymes) and loss (or alteration)
of antigenicity (in the case of antigens)
变性作用 由热、X线或化学物质引起的蛋白物理和生理
特点的变化。这些变化包括活性(酶)和抗原性(抗原)的丧
失。
pepsinogen:
----the inactive precursor (先质,前体) to pepsin, formed
in the cells of the mucous membrane of the stomach and
converted to pepsin by hydrochloric acid during digestion
胃蛋白酶原; 胃蛋白酶的一 种不活跃原，在胃粘膜细胞
中形成并在消化的过程中通过盐酸转化为胃蛋白酶
pepsin:
----a digestive enzyme found in gastric juice that catalyzes
the breakdown of protein to peptides
胃蛋白酶; 胃液中一种消化酶, 加速将蛋白质分解成肽
Para.8
Question:
8.What is the function of antrum ?
In biology, “antrum”( is a general term for a cavity or
chamber which may have specific meaning in reference
to certain organs or sites in the body.
Examples include:
antrum cardiacum---- 贲门窦
 mastoid antrum---- 乳突窦/鼓窦/鼓房
 pyloric antrum---- 幽门窦
 gastric antrum---- 胃窦
 dental antrum---- 牙窦；髓腔
 autrum auris---- 耳道

More examples:
1) The antrum was involved. (胃)窦部受累。
2) The stomach can be divided into fundus, body,
and antrum. 胃可分为底部, 体部和窦部。
3) The Nursing Experience of 93 Cases of Nose
Antrum Endoscopy 鼻内窥镜鼻窦手术93例
护理体会
Para.9
Question:
9.What are the characteristics of the small
intestines?
Para.10-12
Question:
10.What sections make up the small intestines ?
Do they have any different characteristics ?
Para.13
Question:
11.What does this paragraph mainly talk about ?
Limitation of digestion process of the small intestine
Difficult Points
deplete/depletion
ingest/ingestion
resist/resistant/resistance
1.可观察到海洋纤毛虫吞食单细胞生物以获得它们
的叶绿体。
Marine ciliates can be observed ingesting other
single-celled creatures and harvesting their chloroplasts.
2. 这种细菌对某些抗生素耐药。
The bacteria are resistant to (have developed a
resistance to ) some antibiotics.
3. 被组织脱氧的静脉血回到肺进行氧和。
Venous blood is depleted of oxygen by the tissues
and returns to the lungs for oxygenation.
Para.14-15
Question:
12.What is the general function of large intestine ?
Is there anything special about it ?
Para.16
Questions:
13.What does this paragraph mainly talk about ?
14.What components are there in pancreatic juice ?
Para.17-18
Question:
15.What are the functions of liver ?
Difficult Points
Cholesterol
A white crystalline substance, found in animal tissues
and various foods, that is normally synthesized by the
liver and is important as a constituent of cell membranes
and a precursor(前体) to steroid(类固醇) hormones. Its
level in the bloodstream can influence the pathogenesis
of certain conditions, such as the development of
atherosclerotic plaque(动脉粥样硬化斑块) and coronary
artery disease(冠心病).
A good diet can decrease blood cholesterol levels.
Soluble fibre, polyunsaturated fat(多不饱和脂肪)
(especially fish fats which contain omega-3 fatty acids),
and monounsaturated fat(单不饱和脂肪)(such as olive
oil) may all lower cholesterol levels. Regular aerobic
exercise helps to reduce deposition of cholesterol in
blood vessels.
Para.19
Question:
16.What is the general function of gallbladder ?
Difficult Points
bile acids----the organic acids in bile; mostly occurring
as bile salts.
胆汁酸 胆汁中的有机酸, 大多以胆盐存在。
Phrases in the Text
1.
2.
3.
4.
5.
6.
7.
8.
taste receptors
salivary glands
digestive tract
hydrochloric acid
gastric fundus mucosa
amino acids
pancreatic juice
gastrointestinal system