Copyright © by Holt, Rinehart and Winston. All rights reserved. When are sister chromatids formed?...

Copyright © by Holt, Rinehart and Winston. All rights reserved.

When are sister chromatids formed? When are they separated? When are homologous pairs separated?

Question of the DayQuestion of the Day3-73-7


1. What is cancer? 2. What causes cancer?



How Cancer Grows

Quiz make ups

Read Section 8.3 in the Owl Book and answer #s 1-6 on page 156

TodayToday3-73-7


What is a haploid cell (there are multiple correct answers)?



1. What are the four stages of mitosis in order?



Plan for the Unit # 6 Test at the end of next week (Thursday 3-17 or Friday 3-18)

AnnouncementAnnouncement3-103-10


Control of Cell DivisionControl of Cell Division

Cell division in eukaryotes is Cell division in eukaryotes is controlled by many controlled by many proteinsproteins. .

Contact InhibitionContact Inhibition = = when normal when normal cells come in contact with one cells come in contact with one another, growth stopsanother, growth stops


Cancer may result if Cancer may result if cells do not cells do not respond to proteins and/or contact respond to proteins and/or contact inhibitioninhibition..

Contact InhibitionContact Inhibition - - – Cancer cells do not stop dividing Cancer cells do not stop dividing

when they come in contact.when they come in contact.

CancerCancer


CancerCancer

= uncontrolled= uncontrolled cell cell growthgrowth

causes =causes = mutated DNA mutated DNA (genetic or (genetic or environmental)environmental)


Mitosis vs. MeiosisMitosis vs. Meiosis Mitosis produces 2 daughter cells while meiosis produces 4 daughter cells Mitosis produces diploid cells while meiosis produces haploid cells


Mitosis ReviewMitosis Review Genetically – how similar are the daughter Genetically – how similar are the daughter

cells in mitosis?cells in mitosis?– They are identicalThey are identical

When is the DNA copied for the new cell?When is the DNA copied for the new cell?– S phase of interphaseS phase of interphase

What are two things make up What are two things make up chromosomes?chromosomes?– DNA and histones (protein)DNA and histones (protein)

What is the middle part of the chromosome?What is the middle part of the chromosome?– CentromereCentromere

What gets separated during mitosis? What gets separated during mitosis? – Sister chromatids NOT homologous pairsSister chromatids NOT homologous pairs


Meiosis ObjectivesMeiosis Objectives Compare the end products of Compare the end products of

meiosis with those of mitosis.meiosis with those of mitosis. Summarize the events of Summarize the events of

meiosis I.meiosis I. Explain crossing-over and how Explain crossing-over and how

it contributes to the production it contributes to the production of unique individuals.of unique individuals.

Summarize the events of Summarize the events of meiosis II.meiosis II.

Compare spermatogenesis and Compare spermatogenesis and oogenesis.oogenesis.

Define sexual reproduction.Define sexual reproduction.


AssignmentAssignment#s 1-6 on page 156 – Owl #s 1-6 on page 156 – Owl BookBook


Poster Contest

Poster Contest

3-83-8Topics:

The S-phase of Interphase Prophase

Metaphase Anaphase

Telophase Cytokinesis

The chromosome

MAKE SURE YOU GET A CHECKLIST FOR YOUR TOPIC!!!

Creativity

Slogan / Title

Aesthetically pleasing

Accurately descriptive and understandable


What does DIPLOID mean?What does DIPLOID mean?– Cells having Cells having 2 homologous copies2 homologous copies of of

each chromosome (homologous pairs)each chromosome (homologous pairs) What does HAPLOID mean?What does HAPLOID mean?

– Number of chromosomes in a sex cell Number of chromosomes in a sex cell (half the number in a diploid cell)(half the number in a diploid cell)

What are sister chromatids?What are sister chromatids?– Identical copiesIdentical copies

of the same of the same chromosome chromosome

Important vocab. Important vocab. reviewreview


What is are sister chromatids?What is are sister chromatids?– Identical copiesIdentical copies of the same of the same

chromosomechromosome When does the cellWhen does the cell

produce the copy ofproduce the copy ofthe chromatid?the chromatid?– S phase of S phase of

interphase interphase



What are homologous chromosomes?What are homologous chromosomes?– Chromosomes that carry Chromosomes that carry genes for same genes for same

traitstraits (though variation of the trait may (though variation of the trait may differ)differ)

– Allele – Allele – variation variation of a trait of a trait Trait = flower Trait = flower color color

Alleles = genes Alleles = genes for either white for either white or purple or purple flowers flowers



Formation of Haploid Formation of Haploid Cells Cells

Meiosis – the Meiosis – the process of making process of making sex cells.sex cells. makesmakes sperm and eggs sperm and eggs FourFour new haploid cells result new haploid cells result

((gametesgametes)) Meiosis is broken down into Meiosis is broken down into

Meiosis I and Meiosis II.Meiosis I and Meiosis II.


How is meiosis different from mitosis (there is more than one correct answer)?



Plan for the Unit # 6 Test on Friday 3-18

AnnouncementAnnouncement3-143-14


Reviewing ObjectivesReviewing Objectives Describe the structure of a Describe the structure of a

chromosome.chromosome.

How is a prokaryotic chromosome How is a prokaryotic chromosome different than a eukaryotic different than a eukaryotic chromosome?chromosome?

How many chromosomes do you How many chromosomes do you have?have?

How are diploid and haploid cells How are diploid and haploid cells different?different?


cell division in prokaryotes = ???cell division in prokaryotes = ??? What happens during interphase?What happens during interphase? 4 stages of mitosis in order = ???4 stages of mitosis in order = ??? How is cytokinesis in animal cells How is cytokinesis in animal cells

different from cytokinesis in plant different from cytokinesis in plant cells?cells?

How is cell division controlled? How is cell division controlled? What happens if it is not?What happens if it is not?

Reviewing ObjectivesReviewing Objectives


Meiosis I: crossing over takes place homologous chromosomes get separated 2 new haploid cells result


Meiosis II: sister chromatids get separated (like in mitosis) 2 new haploid cells result from each of the cells from meiosis I (total 4 new cells)


During meiosis…During meiosis… Synapsis – Synapsis – pairing of pairing of

homologous chromosomes homologous chromosomes – – this did not occur in mitosisthis did not occur in mitosis


Formation of Haploid Formation of Haploid CellsCells

Crossing-over – when portions of Crossing-over – when portions of homologous chromosomes homologous chromosomes exchange genesexchange genesResults inResults in genetic genetic recombination recombination..

Genetic recombination – Genetic recombination – Regrouping of genes in an Regrouping of genes in an offspring that offspring that results in a results in a genetic makeup that is genetic makeup that is different from the parentsdifferent from the parents


Crossing OverCrossing Over


Crossing Crossing OverOver


Asexual Reproduction = Asexual Reproduction = genes genes identical to parentsidentical to parents– PRO: PRO:

Offspring well adapted to survivalOffspring well adapted to survivalNeed only one parentNeed only one parentFast Fast

– CON: CON: If susceptible to a disease, may kill If susceptible to a disease, may kill off the entire population (b/c off the entire population (b/c all all genes are the samegenes are the same))

Types of ReproductionTypes of Reproduction


Sexual ReproductionSexual Reproduction– PRO: PRO:

Leads to Leads to genetic diversity from genetic diversity from parentsparents

Not all members will die from a Not all members will die from a disease (leads to species evolution)disease (leads to species evolution)

– CON: CON: Need Need two parentstwo parentsTakes longerTakes longer

Why is genetic recombination Why is genetic recombination important?important?


Poster Contest

Poster Contest

3-143-14Topics:

The S-phase of Interphase Prophase

Metaphase Anaphase

Telophase Cytokinesis

The chromosome

MAKE SURE YOU GET A CHECKLIST FOR YOUR TOPIC!!!

Creativity

Slogan / Title

Aesthetically pleasing

Accurately descriptive and understandable


Error in MeiosisError in Meiosis Nondisjunction - Nondisjunction - wwhen hen a set of a set of

homologous chromosomes do not homologous chromosomes do not separateseparate– Means "Means "not coming apartnot coming apart""– Results in gametes with Results in gametes with incorrect incorrect

chromosome #chromosome #

Date post:	26-Mar-2015
Category:	Documents
Upload:	xavier-mcdonald
View:	218 times
Download:	4 times

Copyright © by Holt, Rinehart and Winston. All rights reserved. When are sister chromatids formed?...

Documents