Study mitosis phases according to tables, sketch and make designation.

Pic.3. Mitosis in cell of a back of onions: 1-interfaza, 2 pro-phase, 3 metaphase, 4 anaphase, 5-telofaza, 6-daughter cells, 7 chromosomes.

Task I. Fill in the table.

Enter formulas of the maintenance of a genetic material in the various periods of a mitotic cycle, a phase of a mitosis and meiosis.

Phases and periods	Interphase	mitosis	meiosis - I	Meiosis – II
I. Presythetic II. Synthetic III. Postsythetic А. Prophase • liptotene • zygotene • pachitene • дтплотена • diakinesis B. Metaphase C. Anaphase D. Telophase

V. Fill the missing.

1. The period in the cell activity from the moment of its emergence to death or formation of daughter cells is ….
2. In the field of primary banner of a metaphase chromosome settles down … to which threads of a spindle of division are attached.
3. The site of a molecule of DNA in the field of a secondary banner of spiraled chromosomes is called....
4. The maintenance of a genetic material in G2 the period of interphase ….
5. The phase of meiosis in which there is a conjugation of homologous chromosomes and a crossing-over, is called ….

VI. Set out the correspondence

N, the quantity of DNA 2с is equivalent to number of chromosomes of a diploidic cage.

Place values of the relations of "nc" according to phases of a mitotic cycle.

Phases of a cycle Ratio of "nc"

1. G – 1 a) 2n1c
2. G – 2 b) 2n2c
3. Pro-phase
4. Metaphase
5. Anaphase

6. Telophase

Mitosis phases Processes

1. Pro-phase a) DNA doubling

2. Telophase b) synthesis of histones

3. Interphase c) formation of daughter nucleus

4. Metaphase d) contact of chromosomes with spindle threads

5. Anaphase e) divergence and despiralization of daughter

VII. Find out mistakes

1. In a pro-phase of mitosis occurs:

A) Spiralization of chromatin and formation of visible chromosomes;

B) Dissolution of a nuclear membrane and nuclues;

C) Arrangement of chromosomes on the cell equator.

2. Meiosis is:

A) Cell fission of sexual glands in a reproduction zone;

B) Cell fission of sexual glands in a maturing zone;

C) Cell fission of sexual glands in a zone of reproduction and in a maturing zone.

3. Interkinesis is:

A) interval between two mitoses;

B) Interval between two divisions of meiosis;

C) The period of activity of a cell from its emergence to death or division into the daughters.

VIII. SRSP. (35 min.).

Sort of phases of mitosis and meiosis and also their biological importance

IX. Tests for self-checking (20 min.).

X. Assessment of oral asking, SRS and test control of students (20 min.).

Дата добавления: 2015-10-30