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柳陈坚 Chenjian Liu
Associate professor
Faculty of Bioscience &Technology
Lab. of Applied microbiology
Heredity and gene
• The phenomenon of heredity
1.What is life phenomenon of organisms
why children look like their parents, why the
color and appearance of plants and animal
look like their parents, why some diseases
can occur in their children.
it indicates heredity
The sum of all biological processes by which
particular characteristics are transmitted
from parents to their offspring.
The constancy of a species from generation to
generation and the variation among individuals
within a species.
Would offspring exhibit all of characteristics
they would exhibit some variations
what did Mendel discover
How to prove which kind of special molecule
to be responsible for finishing the task
Through hybrid bean experiment, he raised
two laws and one concept.
• law of segregation
• law of independent assortment
• dominant character, recessive character
• Allele
• The character of organisms is determined
by hereditary
• W. Johannsen raised the name of ‘gene’
• What did Morgan find through fruit fly
hybrid experiment?
• He found the special material was in the
chromosome
• He raised law of linkage and crossing-over
• Then he raised the theory of the gene
They didn’t definite what kind of special material to
cause heredity phenomenon
Why can organisms occur such phenomenon
what kind of molecule could control such phenomenon
The geneticists appreciated that the functional units of
heritable material being found within all living cells in the
1930’s
• In 1928, English microbiologist Griffith
found a phenomenon through
Streptococus pneumoniae experiment.
• In 1944, American microbiologist and his
colleagues were successful on genetic
transformation experiment.
• Finally, DNA was determined as the
genetic material. It can carry genetic
specificity
Chargaff’s Rules
DNA的基因组成（mol％）
origin
G
A
C
T
Pu/Py*
A+C
G+C
G+C
A+T
牛肝脏
21.0
28.3
21.1
29.0
0.97
1.00
0.73
牛精子
22.2
28.7
22.0
27.2
1.03
1.03
0.78
人肝脏
19.5
30.3
19.9
30.3
0.99
1.01
0.65
鸡红血球
20.5
28.8
21.5
29.2
0.97
1.01
0.72
小麦胚
23.2
26.8
22.0
28.0
1.00
0.95
0.82
酵母
18.7
31.3
17.1
32.9
1.00
0.94
0.56
大肠菌
24.9
26.0
25.2
23.9
1.04
1.05
1.00
Blender test (Hershey &his research members
carried out in 1952)
[32P] 标
识DNA
强烈搅拌
感染
[35S] 标
识蛋白
DNA注入
大肠菌
离心分离
嗜菌体增殖
[35S]
进一步增殖
溶菌 · 嗜菌体放出
嗜菌体
含[32P]标识DNA的
不含[35S]标识的蛋白质
[32P]
• In 1953, Watson & Crick raised the
structure of DNA which was double helix
Polynucleotide and its component
Purine
碱基 adenine
adenine
deoxyribose
磷酸
nucleoside
nucleotide
nucleotide
guanine
Pyrimidine
ribose
cytosine thymine
uracil
The structure of DNA
碱基1
核酸是由核
苷为单位连
接而成的链
状高分子化
合物
碱基2
碱基3
碱基4
Phosphodiester
Bond,磷酸二酯键
小沟
大沟
Minor groove
Major
groove
中心法则(central dogma)
复制
转录
DNA
翻译
RNA
遗传物质
蛋白质
遗传物质的条件
在细胞内有一定量存在
物质的安定性
减数分裂后有一般传给子代
遗传性状传给后代
支配遗传性状
允许一定程度的变异
Thank you for
your listening