Тема 2.1.

Генетика. Механизм наследственности.

Занятие 1

Этапы занятия.

1. Изучающее чтение

Inheritance

The phenomenon of similarities between children and their parents is well-known. Our knowledge of the process of heredity enabled us to understand this mechanism. The offspring has two sets of genetic information - one from the mother and one from the father.

New species are formed by adaptation of existing forms. Natural selection is the mechanism by which these changes arise. Without this variety and selection species could not adapt to meet the changing demands of the environment.

The paradox of inheritance is how to reconcile the genetic stability needed to preserve useful characteristics with the genetic variability necessary for evolution. To satisfy both requirements it is necessary to have hereditary units which are stable, but which can be reasserted in an infinite variety of ways.

In 1944 Avery, McCarty and McCleod found out that nucleic acid carry genetic information. In 1952 Hershey and Chase proved that DNA is the hereditary material. And in 1953 Watson and Crick formulated the detailed structure of DNA.

DNA is a double helix of two nucleotide strands where the pentose sugar is always deoxyribose and the organic bases are adenine, guanine, cytosine and thymine, but never uracil.

All species possess different DNA and produce different enzymes. The DNA sequence must be a code that determines which proteins are manufactured. The part of the DNA molecule which specifies a polypeptide is termed a gene. One of the most significant scientific advances in recent years is the development of technology which allows genes to be manipulated, altered and transferred from organism to organism. Thanks to this we got the possibility to manufacture hormones, antibiotics, interferon and vitamins.

Задание 1. Образуйте однокоренные слова, используя префиксы и суффиксы:

Prefix	Base word	Suffix
In- Mis- Non- Re- Un-	accuracy constancy evidence habitat hazard to adapt to compete to lead to predict resistance to suit to vary	-able - al -ant -ate -ent -er - ety - ion, - tion - ity - ive -or - ous

II.Работа над грамматикой

Время Present Continuous

Задание 1. Прочтите информацию на стр 127-128 учебника 1

Задание 2. Выполните упр 1 - 3 на стр 127-128

III. Устная речь

Интерактивная форма – ролевая игра. Студенты получают задание: «Вам предложили провести занятие по теме Открытие законов репродукции. Проанализируйте таблицу Historical review of the main events leading to present-day knowledge of reproduction and heredity и подготовьте обзор по этой теме»

Name	Date	Belief/ Observation/ discovery
Aristotle	384-322 BC	Mixing of male and female semen is like blending two sets of ingredients which gives ‘life’
General scientific belief	Up to 17th century	Simple organisms arise spontaneously out of non-living material
van Leeuwenhoek	1677	Discovered sperm – it was generally believed that these contained miniature organisms which only developed when introduced into a female
de Graaf	1670s	Described the ovarian follicle (later called Graafian follicle)
Lamarck	1809	Proposed theory of evolution based on inheritance of acquired characterisrics
Darwin	1859	On the Origin of Species by Means of Natural Selection was published
Pasteur	1864	Experimentally disproved the theory of spontaneous generation
Sutton	1902	Observed pairing of homologous chromosomes during meiosis and suggested these carried genetic information
Garrod	1908	Postulated mutations as sources of certain hereditary diseases
Johannsen	1909	Coined term ‘gene’ as hereditary unit
Oparin	1923	Suggested theory of origin of life
Avery, McCarty and McCleod	1944	Showed nucleic acid to be the chemical which carried genetic information
Hershey and Chase	1952	Showed DNA to be the hereditary material
Watson and Crick	1953	Formulated the detailed structure of DNA

Занятие 2

Этапы занятия: