Biology 1201A Lecture Notes - Lecture 6: Sister Chromatids, Homologous Chromosome, Synaptonemal Complex

16 views2 pages

violetmole448

9 Apr 2016

School

Department

Course

Professor

For unlimited access to Class Notes, a Class+ subscription is required.

Document Summary

Pro-metaphase i connection of spindle microtubules to kinetochores of homologous chromosomes is random. Different combinations of different alleles at different genes. Outcomes: meiosis- 4 unique cells, mitosis- 2 identical cells. Prophase of meiosis: pairing of homologous chromosomes. Mitosis- occurs in somatic cells, meiosis- occurs in sex cells. Meiosis i- separates homologous chromosomes, mitosis- separates chromatids of chromosomes. Ploidy is different: meiosis has 4 haploid and mitosis has 2 diploid. Physical exchange of sequences between chromatids of homologous chromosomes. Protein complex (synaptonemal complex) forms between homologous chromosomes. Segments of non-sister chromatids cross-over (forming chiasmata) and are swapped. Results in new combinations of alleles on chromosomes. This is how we get 4 genetically unique haploid cells. Homologous chromosomes come together on top of each other, not side by side. Misaligned recombination of homologous chromosomes- could result in duplication. Translocation!- genes on the wrong or non-homologous chromosome. Prometaphase i connection of spindle microtubules to kinetochores of homologous chromosomes is random.

Related Questions

3)During Metaphase I of meiosis, microtubules called spindle fibers attach to the

	homologous pairs of each chromosome
	non-homologous pairs of each chromosome
	non-sister chromatids of each chromosome
	chiasmata of each chromosome
	centrosome of each chromosome

4)Which meiotic process generates genetic diversity?

	Independent assortment
	Transcription
	Mitosis
	Translation

5)Crossing over:

	Occurs between two homologous chromosomes in Meiosis
	Occurs only in Mitosis
	Can occur in Mitosis and Meiosis
	Involves the exchange of DNA between two chromosomes
	Involvs the exchange of centromeres between two chromosomes

What is the purpose of meiosis?

To enable an organism to produce gametes

To allow for growth

To allow an organism to replace damaged cells

Question 2

Select one answer.

10 points

Mitosis results in ________ and meiosis results in ________.

gametes, somatic cells

gametes, gametes

somatic cells, somatic cells

somatic cells, gametes

Question 3

Select one answer.

10 points

Which of the following tasks is accomplished through the processof meiosis?

Cell growth

Production of sperm or eggs

Replacement of dysfunctional cells

Question 4

Select one answer.

10 points

What advantage does sexual reproduction have over asexualreproduction?

All other selections are true.

Sexual reproduction provides more genetic variability

Sexual reproduction doubles the number of chromosomes in aspecies

Sexual reproduction is more efficient

Question 5

Select one answer.

10 points

Crossing over occurs between homologous chromosomes during whatstage of cell division? (Read each option carefully.)

Prophase I of meiosis

Prophase of mitosis

Prophase II of meiosis

Interphase

Question 6

Select one answer.

10 points

Corn has 20 chromosomes. When corn undergoes meiosis how manychromosomes are found in the gametes?

Question 7

Select one answer.

10 points

Homologous chromosomes separate and are pulled to opposite sidesof the cell during what stage of cell division? (Read each optioncarefully.)

Metaphase I of meiosis

Anaphase II of meiosis

Anaphase I of meiosis

Anaphase of mitosis

Question 8

Select one answer.

10 points

Mitosis results in ______ cells and meiosis results in _______cells.

diploid, haploid

haploid, diploid

diploid, diploid

haploid, haploid

jadepug655

Which processes contribute directly to genetic variaion?

? What is meant by ploidy? Diploid? Haploid?

? Know the phases of meiosis?

? Know the differences between meiosis and mitosis.

? What is the major difference between metaphase of mitosis and metaphase I of meiosis?

? What is the major difference between meiosis II & mitosis?

? What is crossing over? ? What is synapsis?

? What are chiasmata?

? What are autosomes?

? What are sex chromosomes? What are the sex chromosomes in human male? Human female?

? What are homologous chromosomes?

? What is genetic recombination?

? What is fertilization? What are gametes?

? What are histones? What is chromatin?

? How many autosomes do humans have? Have many pairs of autosomes? How many pairs of sex chromosomes? What is the total number of chromosomes that human have? ? What are the sites of crossing over called?

? What is a karyotype?

? What is Down syndrome?

? What is polyploidy?

? What is nondisjunction?

? What is trisomy and monosomy

pucecat917

Biology 1201A Lecture Notes - Lecture 6: Sister Chromatids, Homologous Chromosome, Synaptonemal Complex

Document Summary

Get access

Related Documents

Biology 1201A Lecture Notes - Lecture 6: Sister Chromatids, Spindle Apparatus, Genetic Recombination

Biology 1201A Midterm: Biology1201_Test2Outcomes_Week9

Biology 1201A Lecture Notes - Lecture 9: Sister Chromatids, Mendelian Inheritance, Dna Replication

Related Questions