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1、1,Foundations of Genetics（遗传学的建立）,2,Allele:等位基因alternative forms of a gene for a particular characteristic (e.g. attached earlobe(耳垂) genes and free earlobe genes are alternative alleles for ear shape)nonallelic genes:非等位基因,3,dihybrid cross: 双因子杂种杂交AaBb*AaBbtest cross：测交 F1*aa 确定F1是纯合子还是杂合子a cross b
2、etween a heterozygote(异质结合体) of unknown genotype and an individual homozygous(同型的) for the recessive genes in question,4,Dominant:显性的 dominance the member of a pair of alleles that shows its effect in the phenotype whatever other allele is present.recessive:隐性的 recessiveness the member of a pair of
3、alleles that does not shows its effect in the presence of any other allelic partner.,5,Genotype:基因型the catalog of genes of an organism, whether or not these genes are expressed.Karyotype:核型，染色体组型phenotype:表现型the physical, chemical, and psychological 心理的expression of genes possessed by an organism.,6
4、,Germ(种子,胚) plasm theory:种质学说a substance thought to be transmitted in the gametes配子(germ cells) in an unchanged form from generation to generation. The germ plasm was believed to be unaffected by the environment and to give rise to the body cells.,7,种质学说：德国生物学家A.魏斯曼1892年提出的有关遗传物质的学说，认为多细胞的生物体可截然地区分为
5、种质和体质两部分。种质是亲代传递给后代的遗传物质，存留在生殖细胞的染色体上,种质可以发育为新个体的体质,但有一部分仍保持原来的状态作为后代发育的基础，体质可以通过生长和发育而形成为新个体的各个组织和器官，但它不能产生种质。体质受环境影响而获得的变异性状也不能遗传给后代。体质随个体死亡而消失；只有种质才能世代传递，连续不绝。所以这一学说又称为种质连续学说。为后来T.H.摩尔根开创的细胞遗传学和对遗传物质的深入探索奠定了理论基础。,8,Homozygous:纯合的a diploid organism that has two identical alleles for particular cha
6、racteristicheterozygous:杂合的a diploid organism that has two different allelic forms of a particular gene.,9,Incomplete dominance:不完全显性the condition in which two allelic genes have a different effect when they are together as a heterozygote in a diploid cell than either of them have in the homozygous
7、state.Codominance:共显性杂合体中一对等位基因的作用都表现,10,Law of independent assortment:独立分配定律members of one gene pair will separate from each other independently of the members of other gene pairs.,11,Law of segregation:分离定律 when gametes are formed by a diploid organism, the alleles that control a trait(特征) separat
8、e from one another into different gametes, retaining their individuality(个性,个体状态),12,Nondisjunction:不分离the failure of separation of paired chromosomes at metaphase, resulting in one daughter receiving both and the other daughter cell none of the chromosomes in question. Nondisjunction can occur duri
9、ng a meiotic or mitotic division.,13,Pangenesis:泛生论，泛生说the theory of heredity postulating(假设) that germs, humours(体液), or essences migrate from individual body cells to the sex organs and contribute to the gametes.,14,Punnett square:庞纳特方格a method used to determine the probabilities of combination in
10、 a zygote(受精卵),15,Text1. early theories of inheritanceearly ideas of inheritance included Hippocrates theory of pangenesis and August Weismanns germ plasm theory. 遗传学的早期理论包括Hippocrates的泛生说和A.Weismann的种质学说。,16,希波克拉底(希腊文 英文Hippocrates of Cos II 或者 Hippokrates of Kos，约前460前377)被西方尊为“医学之父”的古希腊著名医生，欧洲医学奠
11、基人，古希腊医师，西方医学奠基人。提出“体液(humours)学说”，认为人体由血液(blood)、粘液(phlegm)、黄胆(yellow bile)和黑胆(black bile)四种体液组成，这四种体液的不同配合使人们有不同的体质。他把疾病看作是发展着的现象，认为医师所应医治的不仅是病而是病人；从而改变了当时医学中以巫术和宗教为根据的观念。主张在治疗上注意病人的个性特征、环境因素和生活方式对患病的影响。重视卫生饮食疗法，但也不忽视药物治疗，尤其注意对症治疗和预后。他对骨骼、关节、肌肉等都很有研究。他的医学观点对以后西方医学的发展有巨大影响。,17,August Weismann，(1834
12、1914)德国动物学家 。1834 年1月17日生于法兰克福 ，1914年11月5日卒于弗赖堡 。1856年入格丁根大学学医 。先后在巴登和奥地利当过军医和私人开业医生。1861年在吉森大学从师于德国动物学家K.G.洛伊卡尔特，学习动物发生学及形态学，1863年完成了关于双翅目昆虫变态的论文。1866年担任弗赖堡大学医学系动物学和比较解剖学副教授，1868年在该校创办动物研究所，任第一任所长，1871年升任教授。60年代中期以后因眼疾不得不终止显微镜下的研究而转向遗传、发生和进化问题的理论探讨。他讲授达尔文进化论多年 ，直至1912年退休。,18,Based on experiments wi
13、th mice, Weismann proposed that hereditary information in gametes transmitted traits to progeny.基于小鼠实验，维丝曼提出遗传信息储存在配子中并将遗传信息传递给后代。,19,Both of these views incorporated the blending theory: they held that heritable traits of the two parents blend, so that the distinct characteristics of each are lost
14、in offspring.这两个早期观点合起来形成融合理论：子代拥有父母本混合的遗传特征，而不完全象亲代。,20,2. Gregor Mendel and the birth of GeneticsGregor Mendel, an Augustinian monk in the monastery at Brunn, Austria, is known as the “father of genetics”.孟德尔（公元1822公元1884 ），一名奥地利修道士，众所周知的遗传学之父,21,Having been exposed to theories of the particulate
15、nature of matter while a university student and having a background in mathematics, Mendel carried out a series of carefully planned experiments that demonstrated the particulate nature of heredity. 当他还是大学生时就提出了物质的粒子属性理论，同时他学习数学。孟德尔进行了一系列周密安排的实验来证实遗传的颗粒性。,22,His revolutionary ideas were neither unde
16、rstood nor accepted until many years after Mendel died.直到他去世后，他的创新性理论才被理解和接受。,23,孟德尔于1822年出生在海因珍多弗镇，1843年他进入奥地利布鲁恩一家奥古斯都修道院。1847年他被任命为牧师。从1851年到1853年在维也纳大学学习数学和自然科学。从1854年到1868年在布鲁恩现代学校担任自然科学代课教师。与此同时，孟德尔从1856年起开始进行他的著名的植物育种实验。1865年他推导出了著名的遗传学定律，他将定律用一篇论文表述出来，并将论文呈交给布鲁恩自然历史学会。1866年他的成果被发表在该学会学报上，题目是“植物杂交实验”。三年后又在同一杂志上发表了第二篇论文。1868年孟德尔被任命为牧师会会长，专职行政事务。1900年，孟德尔的研究成果被发现。,24,3.Mendels classic experimentsMendel studied genetics through plant-breeding experiments with the garden pea, a plant species
