Activities Cell Division

Chapters 12-15

• Is this one n or 2n? n

• Identify– Chromatid (DNA)– centromere– chromosome arm

Identify the parts pointed at

• name the stage• metaphase

• what stages come before and after this one?

• Prometaphase (or prophase)

Spindle from centrioles

chromosome

centrioles

A metaphase

B metaphase

Cinterphase

D prophase

E telophase

what organism isthis tissue from?plantname the stages A-E

which of these is notan M stage?interphasewhere in the plant youfind this tissue?meristemwhat is "F"? Cell plate

F

• name the stageanaphase

• what stage comes before and after it?

Metaphase; telophase

• if this is a somaticcell and n=10, how many chromosomes will it have? 20

• name the stageinterphase

• is it part of mitosis?no

• give a visible characteristic.Nuclei are visible, cytoplasm has one color tone.

• what happens during this stage, why is it important?

DNA replication, to have chromosomes ready for the daughter cells

• Is this cell going through mitosis or meiosis?

mitosis

• How do you know?There has been no exchange of DNA

between homologous chromosomes

• Is this cell going throughmitosis or meiosis? meiosis

• How do you know? Crossing-over is taking place between homologous chromosomes

• What specific stage is it in?P1

• What special process isgoing on? Crossing over

• What is the importance of it? Genetic variability in the population

• zsdvsfbdb

Is this mitosis or meiosis? meiosis

Name all the stages.

If 2n= 20 what is the number of chromosomes on each stage?

What type of cell will this occur in? gamete, reproductive cell

Prophase I Metaphase I Anaphase I Telophase I

Prophase II Metaphase II Anaphase II Telophase II

Chromosome number = 2n = 20

Chromosome number = n = 10

• Name the form of cell division seen here. meiosis

• What is the name of the process seen in the second picture? (D)

Crossing over

• What stage of meiosis does the second picture represent? PI

• Why is 'D' important for human race and species in general? Genetic variability

• Name the stages with letters C & E C= telophase II, E= metaphase I

• Determine the number (n or 2n) of chromosomes in B, C and E.

A

B

C

n or 2n? 2n

n or 2n? n

n or 2n?

D

E

• What is a homozygous? Same exact genes in each locus• What is a heterozygous? Different genes in each pair of loci• what is a dominant allele? The one that overpowers the recessive• What is a recessive allele? The one who’s expression is overpower

by the dominant trait• What is complete dominance, incomplete dominance and

codominance? Look in book

• What is F1 and F2? F1 is first generation, F2 is second generation

Using the letter R, draw a Punnett square with a homozygous dominant and a homozygous recessive and find the F1.

J J

j Jj Jj

j Jj Jj

All F1 will be heterozygous (Jj)

Law of Segregation

• P= dominant and p=ressesive• using the symbols given:

– fill in the blanck spaces with the proper symbols

– what is the genotype of each of the F1?

– Using two heterozygotes of F1, make a Punnet square and find the F2.

– What are the proportions of the phenotype in the F2?

– What are the proportions of the genotype in F2?

PP pp

F1

F2

P p

P p

P p

P

PP Pp

p

Pp pp

Pp

F1 gametes

Law of Independant Assortment

• Fill in the gametes and Punnett square

• What are the genotype and phenotype of F1? Yellow and smooth

• What are the proportions of the genotype and phenotype of F2?

9 yellow and smooth (Y_R_)

3 yellow and rough (Y_rr)

3 green and smooth (yyR_)

1 green and rough (yyrr)

YR Yr yR yr

F1

F2

YYRR yyrr

YR yr

YyRr

YR

YYRR YYRr YyRR YyRr

Yr

YYRr YYrr YyRr Yyrr

yR

YyRR YyRr yyRR yyRr

yr

YyRr Yyrr yyRr yyrr

Incompletedominance

• Write down the symbols of each generation (P, F1 and F2)

• Write down the genotypes and gametes produced by P and F1.

• Fill in the gametes in the Punnett square and find out the genotypes and their proportions of the possible F2 offspring.

1:2:1 red (CRCR), pink (CRCW), white (CWCW)

CRCR CWCW

CR CW

CRCW

(pink)

CR CW

CR CW

CR CRCR CRCW

CW CRCW CWCW

Codominance

• Put the possible gametes of generation P, both of blood type AB+ (assuming the Rh is heterozygous)

• Find out the genotype and phenotype of the F1

• Determine the proportions of each one of the phenotypes of F1.

• AB+ = 6 A+ = 3• AB - = 2 B+ = 3• A - = 1 B - = 1

IAD IBD IAd IBd

IAD IAIADD IAIBDD IAIADd IAIBDd A+ AB+ A+ AB+

IBD IAIBDD IBIBDD IAIBDd IBIBDd AB+ B+ AB+ B+

IAd IAIADd IAIBDd IAIAdd IAIBdd A+ AB+ A - AB –

IBd IAIBDd IBIBDd IAIB dd IBIBdd

AB+ B+ AB - B -

• what is the difference between the next gene mutations Look in book.– Deletion– Duplication– Inversion– reciprocal translation

define:

• syndrome

• disorder

• aneuploid

• trisomic

• oogenesis