Meiosis

Meiosis
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Slide 1: Tekstslide
BiologieMiddelbare schoolvwoLeerjaar 4

In deze les zitten 43 slides, met interactieve quizzen, tekstslides en 2 videos.

time-iconLesduur is: 30 min

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Meiosis

Slide 1 - Tekstslide

Learning objectives
  • List and describe the phases of meiosis
  •  Describe changes in number of chromosomes during the steps of meiosis
  • Describe changes in DNA content during the steps of meiosis

Slide 2 - Tekstslide

Chromosome numbers
Unique per species

Slide 3 - Tekstslide

Which best describes the amount of chromosomes during the cell cycle with mitosis?
A
2n -> 2n+2n
B
2n -> n + n
C
n -> n+n
D
n -> 2n +2n

Slide 4 - Quizvraag

At the end of mitosis you end up with:
A
2 genetically identical daughter cells
B
4 genetically identical daughter cells
C
2 genetically different daughter cells
D
4 genetically different daughter cells

Slide 5 - Quizvraag

Each homologous pair contains similar genes but different variants
A
true
B
false

Slide 6 - Quizvraag

Meiosis
  • Goal: create haploid cells that will become the gametes
  • Interphase is still the same
  • Challenge: how to make sure all cells end up with one of each type of chromosome to make sure their set of genes is complete 

Slide 7 - Tekstslide

Meiosis
  • PMAT twice
  • Meiosis 1:  
    - Splitting homologous pairs
    - 2n --> n+n
  • Meiosis 2:
    - Splitting chromatids
    - n --> n+n: end results is 4 haploid cells

Slide 8 - Tekstslide

Prophase 1
  • Nuclear membrane disappears
  • Homologous pairs stay together
  • Crossing over creates variation
  • Spindle appears

Slide 9 - Tekstslide

Metaphase 1
  • Chromosome line up on the equator in pairs
  • Homologous pairs still together
  • Each centriole connects a spindle fibre to one member of the pair 

Slide 10 - Tekstslide

Anaphase 1
  • Spindle fibers pull the homologous pairs apart
  • Sister chromatids stay attached! 

Slide 11 - Tekstslide

Telophase 1
  • Nuclear membranes form 

Slide 12 - Tekstslide

Cytokinesis
  • Cytoplasm splits
  • Each cell is now haploid 

Slide 13 - Tekstslide

Prophase 2
  • Nuclear membrane disappears
  • Spindle forms
  • No crossing over! 

Slide 14 - Tekstslide

Metaphase 2
  • Chromosome line up at the equator
  • Each chromosome connect to two spindle fibers 

Slide 15 - Tekstslide

Anaphase 2
  • Chromatids are pulled apart 

Slide 16 - Tekstslide

Telophase 2
  • Nuclear membranes form 

Slide 17 - Tekstslide

Cytokinesis
  • Cytoplasm splits
  • 4 unique haploid cells 

Slide 18 - Tekstslide

GENETIC VARIATION
What are the five sources of genetic variation?

Slide 19 - Tekstslide

Slide 20 - Tekstslide

Slide 21 - Tekstslide

Slide 22 - Tekstslide

An ejaculation of a healthy man consists of 2-5 million sperm cells. Independent assortment has led to a huge genetic variation. Will all possible gametes be present in this ejaculation?

Slide 23 - Open vraag

Slide 24 - Tekstslide

MUTATIONS
Alterations in the genome of an organism:
They can be spontaneous (molecular decay)
Due to environmental influences (radiation, mutagens)

Slide 25 - Tekstslide

What are the five sources of genetic variation?

Slide 26 - Open vraag

Learning objectives
  • List and describe the phases of meiosis
  •  Describe changes in number of chromosomes during the steps of meiosis
  • Describe changes in DNA content during the steps of meiosis

Slide 27 - Tekstslide

Work to be done
  • Watch the video on the next slide
  • Finish Biozone worksheets 136, 139 and 141
  • Finish assessment questions Glencoe pg. 289: q. 1 – 11

Slide 28 - Tekstslide

Slide 29 - Video

Please order the four stages of Mitosis!
Prophase
Metaphase
Anaphase
Telophase
Interphase

Slide 30 - Sleepvraag

What phase of mitosis do these images show?
Prophase
Metaphase
Anaphase
Telophase

Slide 31 - Sleepvraag

3

Slide 32 - Video

00:22
Look at how the chromosomes are arranged at this point. What stage of mitosis is this?
A
Metaphase
B
Prophase
C
Anaphase
D
Telophase

Slide 33 - Quizvraag

00:35
A hard cell plate formed in the middle of this cell after mitosis. What type of cell did we just watch divide?
A
Plant cell
B
Animal cell

Slide 34 - Quizvraag

00:45
The cell in the video just underwent anaphase, how do you know this?
A
The cell split into two, distinct cells
B
The chromosomes pulled "away" from each other
C
The chromosomes arranged themselves on the equator of the cell
D
The cell's DNA was just replicated

Slide 35 - Quizvraag

What phase of mitosis do these images show?
Prophase
Metaphase
Anaphase
Telophase

Slide 36 - Sleepvraag

Which best describes the amount of chromosomes during meiosis 1?
A
2n -> 2n+2n
B
2n -> n + n
C
n -> n+n
D
n -> 2n +2n

Slide 37 - Quizvraag

Which best describes the amount of chromosomes during meiosis 2?
A
2n -> 2n+2n
B
2n -> n + n
C
n -> n+n
D
n -> 2n +2n

Slide 38 - Quizvraag

C is a process happening during.. in ..
A
Anaphase / Meiosis 1
B
Anaphase / Mitosis
C
Metaphase / Meiosis 1
D
Metaphase / Mitosis

Slide 39 - Quizvraag

At the end of meiosis you end up with:
A
2 genetically identical daughter cells
B
4 genetically identical daughter cells
C
2 genetically different daughter cells
D
4 genetically different daughter cells

Slide 40 - Quizvraag

In anaphase of meiosis 2 the number of chromosomes is haploid
A
true
B
false

Slide 41 - Quizvraag

Crossing over takes place during:
A
Meiosis 1 / Prophase
B
Meiosis 2 / Prophase
C
Meiosis 2 / Anaphase
D
Meiosis 2 / Metaphase

Slide 42 - Quizvraag

Crossing over can only occur between homologous pairs
A
true
B
false

Slide 43 - Quizvraag