How Meiosis Creates Variation

1. Watch this Video

2. Read This Summary

The Big Picture: There are Two Ways that Meiosis Generates Variation

Independent Assortment
Crossing Over and Genetic Recombination

Independent Assortment

Definition: The random arrangement and separation of homologous chromosomes during meiosis, specifically between prophase I and metaphase I.
Key Events:
- During prophase I, homologous chromosomes pair up, with maternal and paternal chromosomes finding and embracing their homologous partners.
- During metaphase I, homologous pairs are pulled randomly to the cell’s equator. The orientation of each pair is independent of every other pair.
How It Works:
- As the homologous pairs line up on the cell equator, each homologous pair’s arrangement is like flipping a coin—random and independent of other pairs.
- This randomness leads to a variety of chromosome combinations in gametes.
The number of potential combination depends on the number of chromosomes
- With 2 homologous pairs, there are 2² (4) possible chromosomal combinations in the gametes
- With 3 homologous pairs, there are 2³ (8) combinations.
- For humans, with 23 pairs, there are 2²³ (8,388,608) combinations.
Impact on Variation among Siblings:
- In humans, with 23 homologous pairs, the chance of two siblings inheriting identical chromosomal arrays from both parents is approximately 1 in 70 trillion. That’s why siblings are genetically unique.

Crossing Over and Genetic Recombination

Definition: The exchange of DNA segments between homologous chromosomes during prophase I of meiosis.
Key Events:
- Synapsis: Homologous chromosomes pair and embrace tightly.
- Chiasma Formation: At specific points, DNA segments are exchanged between homologues.
- Result: Recombinant chromosomes, each containing a mix of maternal and paternal genetic material.
Impact on Diversity:
- Creates chromosomes with unique DNA sequences.
- Ensures that each gamete has novel genetic information.

Fertilization: A Third Generator of Diversity

Definition: The random combination of sperm and egg from different individuals during fertilization.
How It Contributes:
- Independent assortment and crossing over in both parents produce diverse gametes.
- Fertilization combines these gametes, further amplifying genetic variation.

How Sexual Reproduction Creates Diversity

Independent Assortment: Random array of chromosomes in gametes.
Crossing Over: Formation of recombinant chromosomes with unique DNA.
Fertilization: Random combination of gametes from two individuals.

These mechanisms explain the vast genetic variation in sexually reproducing eukaryotic organisms. Among eukaryotes, meiosis and fertilization are the foundation for biological diversity.

3. Complete These Flashcards

[qdeck]
[h] How Meiosis Creates Variation

[q] What are the two ways meiosis generates variation?
[a] 1. Independent assortment
2. Crossing over and genetic recombination

[q] What is independent assortment?
[a] The random arrangement and separation of homologous chromosomes during meiosis, particularly between prophase I and metaphase I.

[q] When does independent assortment occur in meiosis?
[a] It occurs between prophase I and metaphase I, as homologous chromosomes pair up and align randomly at the cell equator.

[q] How does independent assortment generate genetic diversity?
[a] The orientation of each homologous pair is independent of others, leading to a variety of chromosome combinations in gametes.

[q] What is the mathematical impact of independent assortment on genetic variation?
[a]

With 2 homologous pairs, there are 2² (4) possible gamete combinations.
With 3 homologous pairs, there are 2³ (8) combinations.
For humans, with 23 pairs, there are 2²³ (8,388,608) possible combinations.

[q] What is the chance of two siblings having the same chromosomal inheritance from both parents?
[a] Approximately 1 in 70 trillion, due to the combined effects of independent assortment and the randomness of gamete formation.

[q] What is crossing over in meiosis?
[a] The exchange of DNA segments between homologous chromosomes during prophase I, resulting in recombinant chromosomes with unique genetic sequences.

[q] What is synapsis, and how does it relate to crossing over?
[a] Synapsis is the pairing and tight embrace of homologous chromosomes during prophase I. This pairing facilitates crossing over, where DNA is exchanged between homologues at points called chiasmata.

[q] What are recombinant chromosomes?
[a] Chromosomes created during crossing over, containing a mix of maternal and paternal DNA, resulting in unique genetic combinations.

[q] How does crossing over contribute to genetic diversity?
[a] By creating recombinant chromosomes, crossing over ensures that each gamete has a unique genetic makeup.

[q] What is fertilization, and how does it contribute to diversity?
[a] Fertilization is the random combination of sperm and egg from different individuals, further amplifying genetic variation by combining diverse gametes.

[q] What are the three mechanisms by which sexual reproduction creates diversity?
[a] 1. Independent assortment
2. Crossing over and genetic recombination
3. Fertilization

[/qdeck]

4. Complete These Quizzes

4.1. Independent Assortment

[qwiz]

[h]Independent Assortment: Checking Understanding

[i]

[q]The key idea behind independent assortment is that each pair of homologous chromosomes is divided up [hangman] from every other pair.

[c]aW5kZXBlbmRlbnRseQ==[Qq]

[q]During metaphase 1 (shown below) the way that maternal and paternal chromosomes line up is as [hangman] as a coin toss.

[c]cmFuZG9t[Qq]

[q]INSTRUCTIONS: spell out the numbers.

The cell below has [hangman] homologous pairs. That means that meiosis can create [hangman] possible combinations of chromosomes.

[c]dHdv[Qq]

[c]Zm91cg==[Qq]

[q]INSTRUCTIONS: spell out the numbers.

In a cell with three homologous chromosomes, meiosis can result in [hangman] possible combinations of chromosomes.

[c]ZWlnaHQ=[Qq]

[q multiple_choice=”true”]In a cell with a total of 12 chromosomes, what would be the number of unique gametes that could form through independent assortment?

[c]MTI=^Mg==[Qq]

[f]Tm8uIEEgY2VsbCB3aXRoIDEyIGNocm9tb3NvbWVzIGhhcyBob3cgbWFueSBob21vbG9nb3VzIHBhaXJzPyBGaWd1cmUgdGhhdCBvdXQsIGFuZCB0aGVuIHNldCB1cCB0aGUgZm9ybXVsYSBmb3IgdGhlIG51bWJlciBvZiBwb3NzaWJsZSBnYW1ldGVzLCB3aGljaCBpcyAy^{KG51bWJlciBvZiBob21vbG9nb3VzIHBhaXJzKQ==}Lg==[Qq]

[c]Ng==^Mg==[Qq]

[f]Tm8uIEl0IGxvb2tzIGxpa2UgeW91IGZpZ3VyZWQgb3V0IHRoZSBudW1iZXIgb2YgaG9tb2xvZ291cyBwYWlycywgd2hpY2ggaXMgc2l4LiBOb3cgc2V0IHVwIHRoZSBmb3JtdWxhIGZvciB0aGUgbnVtYmVyIG9mIHBvc3NpYmxlIGdhbWV0ZXMsIHdoaWNoIGlzIDI=^{KG51bWJlciBvZiBob21vbG9nb3VzIHBhaXJzKQ==}Lg==[Qq]

[c]Mg==^MTI=[Qq]

[f]Tm8uIFRoZSBmb3JtdWxhIGZvciB0aGUgbnVtYmVyIG9mIHBvc3NpYmxlIGdhbWV0ZXMgaXMgMg==^{KG51bWJlciBvZiBob21vbG9nb3VzIHBhaXJzKQ==}LiBJbiBhIGNlbGwgd2l0aCAxMiBjaHJvbW9zb21lcywgaG93IG1hbnkgaG9tb2xvZ291cyBwYWlycyBhcmUgdGhlcmU/[Qq]

[c]Mg ==^Ng==[Qq]

[f]RXhjZWxsZW50LiBUaGUgZm9ybXVsYSBmb3IgdGhlIG51bWJlciBvZiBwb3NzaWJsZSBnYW1ldGVzIGlzIDI=^{KG51bWJlciBvZiBob21vbG9nb3VzIHBhaXJzKQ==}LiBJbiBhIGNlbGwgd2l0aCAxMiBjaHJvbW9zb21lcywgdGhlcmUgYXJlIHNpeCBob21vbG9nb3VzIHBhaXJzLCBzbyB0aGUgbnVtYmVyIG9mIHBvc3NpYmxlIGdhbWV0ZXMgaXMgMg==^{Ng==_Lg==[Qq]}

[q multiple_choice=”true”]Dogs have 78 chromosomes. What’s the number of unique gametes a dog could form through independent assortment?

[c]Nzg=^Mg==[Qq]

[f]Tm8uIEEgY2VsbCB3aXRoIDc4IGNocm9tb3NvbWVzIGhhcyBob3cgbWFueSBob21vbG9nb3VzIHBhaXJzPyBGaWd1cmUgdGhhdCBvdXQsIGFuZCB0aGVuIHNldCB1cCB0aGUgZm9ybXVsYSBmb3IgdGhlIG51bWJlciBvZiBwb3NzaWJsZSBnYW1ldGVzLCB3aGljaCBpcyAy^{KG51bWJlciBvZiBob21vbG9nb3VzIHBhaXJzKQ==}Lg==[Qq]

[c]Mg ==^Mzk=[Qq]

[f]V2F5IHRvIGdvLiBUaGUgZm9ybXVsYSBmb3IgdGhlIG51bWJlciBvZiBwb3NzaWJsZSBnYW1ldGVzIGlzIDI=^{KG51bWJlciBvZiBob21vbG9nb3VzIHBhaXJzKQ==}LiBJbiBkb2dzLCB3aGljaCBoYXZlIDc4IGNocm9tb3NvbWVzLCB0aGVyZSBhcmUgMzkgaG9tb2xvZ291cyBwYWlycywgc28gdGhlIG51bWJlciBvZiBwb3NzaWJsZSBnYW1ldGVzIGlzIDI=^{Mzk=_Lg==[Qq]}

[c]Mzk=^Mg==[Qq]

[f]Tm8uIEl0IGxvb2tzIGxpa2UgeW91IGZpZ3VyZWQgb3V0IHRoZSBudW1iZXIgb2YgaG9tb2xvZ291cyBwYWlycywgd2hpY2ggaXMgMzkuIE5vdyBzZXQgdXAgdGhlIGZvcm11bGEgZm9yIHRoZSBudW1iZXIgb2YgcG9zc2libGUgZ2FtZXRlcywgd2hpY2ggaXMgMg==^{KG51bWJlciBvZiBob21vbG9nb3VzIHBhaXJzKQ==}Lg==[Qq]

[c]Mg==^Nzg=[Qq]

[f]Tm8uIFRoZSBmb3JtdWxhIGZvciB0aGUgbnVtYmVyIG9mIHBvc3NpYmxlIGdhbWV0ZXMgaXMgMg==^{KG51bWJlciBvZiBob21vbG9nb3VzIHBhaXJzKQ==}LiBJbiBhIGNlbGwgd2l0aCA3OCBjaHJvbW9zb21lcywgaG93IG1hbnkgaG9tb2xvZ291cyBwYWlycyBhcmUgdGhlcmU/[Qq]

[x][restart]

[/qwiz]

4.2. How Meiosis Creates Variation

The quiz below covers the two ways that meiosis creates variation:

crossing over
independent assortment

[qwiz]

[h]Quiz: Meiosis and Variation
[i]

[q] As shown in the diagram below, the pairing up of homologous chromosomes is also known as

[c]IGEgY2hpYXNtYQ==[Qq]

[c]IHByb3BoYXNlIDE=[Qq]

[c]IHN5bm Fwc2lz[Qq]

[c]IHRldHJhZGl6YXRpb24=[Qq]

[f]IE5vLiBBIGNoaWFzbWEgaXMgYSBzcG90IHdoZXJlIHRoZSBjaHJvbWF0aWRzIGxpbmsgdG9nZXRoZXIuIFlvdSBjYW4gc2VlIHRoZSBjaGlhc21hLCBidXQgdGhlIHByb2Nlc3MgaGFzIGEgZGlmZmVyZW50IG5hbWUu[Qq]

[f]IE5vLiBUaGlzIHByb2Nlc3MgaXMgb2NjdXJyaW5nIGR1cmluZyBwcm9waGFzZSAxLCBidXQgdGhhdOKAmXMgbm90IHRoZSBuYW1lIGZvciB0aGUgcGFpcmluZyB1cCBvZiBob21vbG9nb3VzIGNocm9tb3NvbWVzLg==[Qq]

[f]IENvcnJlY3QuIFN5bmFwc2lzIGlzIHRoZSBuYW1lIGZvciB0aGUgcHJvY2VzcyB3aGVyZSBob21vbG9nb3VzIGNocm9tb3NvbWVzIHBhaXIgdXAgKGFuZCBleGNoYW5nZSBnZW5lcyku[Qq]

[f]IE5vLiBUaGUgdW5pdCB0aGF04oCZcyBtYWRlIG9mIHR3byBob21vbG9nb3VzIGNocm9tb3NvbWVzLCB3aGljaCBpbiB0dXJuIGNvbnNpc3RzIG9mIGZvdXIgc2lzdGVyIGNocm9tYXRpZHMsIGlzIGtub3duIGFzIGEgdGV0cmFkLiBCdXQgdGV0cmFkaXphdGlvbiBpcyBhIHRlcm0gdGhhdCBJIG1hZGUgdXAganVzdCBhcyBhIGRpc3RyYWN0b3IuIE5leHQgdGltZSwgbWFrZSBhbm90aGVyIGNob2ljZS4=[Qq]

[q] In the diagram below, these paired homologous chromosomes can also be referred to as a

[c]IGEgY2hpYXNtYQ==

Cg==[Qq]

[c]IGNyb3Nzb3ZlciBwb2ludA==[Qq]

[c]IHN5bmFwc2lz[Qq]

[c]IHRldH JhZA==[Qq]

[f]IE5vLiBBIGNoaWFzbWEgaXMgYSBzcG90IHdoZXJlIHRoZSBjaHJvbWF0aWRzIGxpbmsgdG9nZXRoZXIuIFlvdSBjYW4gc2VlIHRoZSBjaGlhc21hLCBidXQgdGhlIG92ZXJhbGwgZ3JvdXBpbmcgaGFzIGEgZGlmZmVyZW50IG5hbWUuIE9uZSAob2JzY3VyZSkgaGludCBpcyB0aGF0IHRoZXJlIGFyZSBmb3VyIHNpc3RlciBjaHJvbWF0aWRzLiBUaGluayBvZiBhIHByZWZpeCB0aGF0IG1lYW5zIGZvdXImIzgyMzA7[Qq]

[f]IE5vLiBUaGUgYXJlYSB3aGVyZSB0aGUgYXJtcyBvZiB0aGUgY2hyb21hdGlkcyBhcmUgb3ZlcmxhcHBpbmcgbWF5LCBpbmRlZWQsIGJlIGEgY3Jvc3NvdmVyIHBvaW50LCBidXQgdGhhdOKAmXMgbm90IHRoZSBuYW1lIGZvciB0aGlzIHVuaXQgb2YgZm91ciBzaXN0ZXIgY2hyb21hdGlkcy4=[Qq]

[f]IE5vLiBTeW5hcHNpcyBpcyB0aGUgbmFtZSBmb3IgdGhlIHByb2Nlc3Mgd2hlcmUgaG9tb2xvZ291cyBjaHJvbW9zb21lcyBwYWlyIHVwIChhbmQgZXhjaGFuZ2UgZ2VuZXMpLiBCdXQgaXTigJlzIG5vdCB0aGUgbmFtZSBmb3IgdGhpcyB1bml0IG9mIGZvdXIgc2lzdGVyIGNocm9tYXRpZHMu[Qq]

[f]IFllcy4gVGhlIHVuaXQgdGhhdOKAmXMgbWFkZSBvZiB0d28gaG9tb2xvZ291cyBjaHJvbW9zb21lcywgd2hpY2ggaW4gdHVybiBjb25zaXN0cyBvZiBmb3VyIHNpc3RlciBjaHJvbWF0aWRzLCBpcyBhbHNvIGtub3duIGFzIGEgdGV0cmFkLg==

Cg==

[Qq]

[q] In the diagram below, the arrow indicates a

[c]IGNoaW FzbWE=[Qq]

[c]IGNyb3Nzb3ZlciBwb2ludA==[Qq]

[c]IHN5bmFwc2lz[Qq]

[c]IHRldHJhZA==[Qq]

[f]IFllcy4gQSBjaGlhc21hIGlzIGEgc3BvdCB3aGVyZSB0aGUgY2hyb21hdGlkcyBsaW5rIHRvZ2V0aGVyLg==[Qq]

[f]IE5vLiBTeW5hcHNpcyBpcyB0aGUgbmFtZSBmb3IgdGhlIHByb2Nlc3Mgd2hlcmUgaG9tb2xvZ291cyBjaHJvbW9zb21lcyBwYWlyIHVwIChhbmQgZXhjaGFuZ2UgZ2VuZXMpLiBCdXQgdGhhdOKAmXMgbm90IHRoZSBuYW1lIGZvciB0aGlzIHBvaW50IG9mIG92ZXJsYXAu[Qq]

[f]IE5vLiBUaGUgdW5pdCB0aGF04oCZcyBtYWRlIG9mIHR3byBob21vbG9nb3VzIGNocm9tb3NvbWVzLCB3aGljaCBpbiB0dXJuIGNvbnNpc3RzIG9mIGZvdXIgc2lzdGVyIGNocm9tYXRpZHMsIGlzIGtub3duIGFzIGEgdGV0cmFkLiBCdXQgdGhhdOKAmXMgbm90IHRoZSBuYW1lIGZvciB0aGlzIHBvaW50IG9mIG92ZXJsYXAu

Cg==

[Qq]

[q] The tetrad shown below shows what process?

[c]IEROQSByZXBsaWNhdGlvbg==[Qq]

[c]IENyb3NzaW 5nIG92ZXI=[Qq]

[c]IEluZGVwZW5kZW50IGFzc29ydG1lbnQ=[Qq]

[f]IE5vLiBUaGUgRE5BIHdhcyByZXBsaWNhdGVkIGR1cmluZyBpbnRlcnBoYXNlLiBGb3IgYSBiZXR0ZXIgYXBwcm9hY2ggdG8gdGhpcyBxdWVzdGlvbiwgbm90ZSBob3cgdGhlIHRpcHMgb2YgdHdvIG9mIHRoZSBjaHJvbWF0aWRzIGhhdmUgc3dpdGNoZWQgY29sb3Iu[Qq]

[f]IFllcy4gVGhlIHRpcHMgb2YgZWFjaCBjaHJvbWF0aWQgaGF2ZSBjcm9zc2VkIG92ZXIgdG8gdGhlIG90aGVyIG1lbWJlciBvZiB0aGUgaG9tb2xvZ291cyBwYWlyLiBUaGUgcmVzdWx0IGlzIHJlY29tYmluYW50IGNocm9tb3NvbWVzLCBicmFuZC1uZXcgcGllY2VzIG9mIEROQS4=[Qq]

[f]IE5vLiBXaGlsZSB0aGF04oCZcyBhbiBpbXBvcnRhbnQgZmVhdHVyZSBvZiBtZWlvc2lzLCBpdCBvY2N1cnMgbGF0ZXIgaW4gbWVpb3NpcywgYWZ0ZXIgcHJvcGhhc2UgMS4=

Cg==

[Qq]

[q] The tetrad shown here illustrates the creation of

[c]IHJlcGxpY2F0ZWQgRE5B[Qq]

[c]IGhvbW9sb2dvdXMgcGFpcnM=[Qq]

[c]IHJlY29tYmluYW50 IGNocm9tb3NvbWVz[Qq]

[f]IE5vLiBUaGUgRE5BIHdhcyByZXBsaWNhdGVkIGR1cmluZyBpbnRlcnBoYXNlLiBBcyBhIGhpbnQsIG5vdGUgdGhhdCBhcyBhIHJlc3VsdCBvZiBjcm9zc2luZyBvdmVyLCB0aGVyZeKAmXMgYSBuZXcgY29tYmluYXRpb24gb2YgZ2VuZXMu[Qq]

[f]IE5vLiBUaGUgdGV0cmFkIGlzIGEgaG9tb2xvZ291cyBwYWlyLCBidXQgdGhhdOKAmXMgbm90IHdoYXTigJlzIGJlaW5nIGNyZWF0ZWQuIEFzIGEgaGludCwgbm90ZSB0aGF0IGFzIGEgcmVzdWx0IG9mIGNyb3NzaW5nIG92ZXIsIHRoZXJl4oCZcyBhIG5ldyBjb21iaW5hdGlvbiBvZiBnZW5lcy4=[Qq]

[f]IFllcy4gQ3Jvc3Npbmcgb3ZlciByZXN1bHRzIGluIGJyYW5kIG5ldyBzZXF1ZW5jZXMgb2YgRE5BLCB3aXRoIG5ldyBjb21iaW5hdGlvbnMgb2YgZ2VuZXM7IEhlbmNlLCByZWNvbWJpbmFudCBjaHJvbW9zb21lcy4=

Cg==

[Qq]

[q] This diagram shows two homologous chromosomes at the end of prophase 1. What’s the best explanation for the region of swapped color on each of the innermost chromatids?

[c]IEROQSBwb2x5bWVyYXNlIGFuZCBvdGhlciBlbnp5bWVzIGNvcGllZCB0aGUgY2hyb21vc29tYWwgRE5BLg==[Qq]

[c]IGdlbmV0aWMgcmVj b21iaW5hdGlvbg==[Qq]

[c]IGluZGVwZW5kZW50IGFzc29ydG1lbnQ=[Qq]

[f]IE5vLiBUaGF0IGRpZCBoYXBwZW4gZHVyaW5nIGludGVycGhhc2UsIGJ1dCBpdCBkb2VzbuKAmXQgZXhwbGFpbiB0aGUgc3dhcHBlZCBjaHJvbW9zb21hbCByZWdpb25zIG9uIHRoZSBib3R0b20gb2YgdGhlIGNocm9tYXRpZHMu[Qq]

[f]IFllcy4gVGhlIGhvbW9sb2dvdXMgY2hyb21vc29tZXMgaGF2ZSBzd2FwcGVkIHJlZ2lvbnMgb2YgZ2VuZXMuIEFzIGEgcmVzdWx0LCB0aGV54oCZdmUgZm9ybWVkIGJyYW5kIG5ldywgcmVjb21iaW5hbnQgY2hyb21vc29tZXMu[Qq]

[f]IE5vLiBJbmRlcGVuZGVudCBhc3NvcnRtZW50IGlzIGFuIGltcG9ydGFudCBzb3VyY2Ugb2YgdmFyaWF0aW9uLCBidXQgaXQgb2NjdXJzIGFmdGVyIHN5bmFwc2lzLg==

Cg==

[Qq]

[q] What’s the big idea behind this diagram of metaphase 1?

[c]IE1laW9zaXMgY3JlYXRlcyB2YXJpYXRpb24gdG hyb3VnaCBpbmRlcGVuZGVudCBhc3NvcnRtZW50[Qq]

[c]IE1laW9zaXMgcmVkdWNlcyBjaHJvbW9zb21lIG51bWJlci4=[Qq]

[f]IFllcy4gQmVjYXVzZSBob21vbG9nb3VzIGNocm9tb3NvbWVzIHJhbmRvbWx5IGxpbmUgdXAgZHVyaW5nIG1ldGFwaGFzZSwgbWF0ZXJuYWwgYW5kIHBhdGVybmFsIGNocm9tb3NvbWVzIGFyZSByYW5kb21seSBtaXhlZCB1cCBkdXJpbmcgZ2FtZXRlIGNyZWF0aW9uLiBUaGF04oCZcyBhbiBpbXBvcnRhbnQgc291cmNlIG9mIHRoZSB2YXJpYXRpb24gdGhhdCBjb21lcyBvdXQgb2YgbWVpb3Npcy4=[Qq]

[f]IE5vLiBNZWlvc2lzIGRvZXMgcmVkdWNlIGNocm9tb3NvbWUgbnVtYmVyLiBCdXQgdGhlIGlkZWEgaGVyZSByZWxhdGVzIHRvIHRoZSBjcmVhdGlvbiBvZiB2YXJpYXRpb24gdGhyb3VnaCByYW5kb20gbWl4aW5nIGFuZCBtYXRjaGluZyBvZiBtYXRlcm5hbCBhbmQgcGF0ZXJuYWwgY2hyb21vc29tZXMsIGFuZCB0aGF0IGNvbWVzIGFib3V0IHRocm91Z2ggdGhlIHdheSB0aGF0IGNocm9tb3NvbWVzIHJhbmRvbWx5IGxpbmUgdXAgZHVyaW5nIG1ldGFwaGFzZSAxLg==

Cg==

[Qq]

[q] In an organism with four chromosomes, or two homologous pairs (which is what is shown in this diagram) how many combinations of maternal and paternal chromosomes can occur in the gametes?

[c]IDE=[Qq]

[c]IDI=[Qq]

[c]IDM=[Qq]

[c]ID Q=[Qq]

[f]IE5vLiBFYWNoIG9mIHRoZSBob21vbG9nb3VzIHBhaXJzIGhhcyB0d28gcG9zc2libGUgb3JpZW50YXRpb25zIChpbiB0aGlzIGRpYWdyYW0sIHRoYXQgd291bGQgYW1vdW50IHRvIHR3byB3YXlzIG9mIGZhY2luZyBub3J0aCBvciBzb3V0aCkuIFRoZSBudW1iZXIgb2YgcG9zc2libGUgYXJyYW5nZW1lbnRzIGlzIHR3byB0byB0aGUgbnVtYmVyIG9mIHBhaXJzIChpbiB0aGlzIGNhc2UsIHR3byBzcXVhcmVkKS4=[Qq]

[f]IEV4YWN0bHkuIEVhY2ggb2YgdGhlIGhvbW9sb2dvdXMgcGFpcnMgaGFzIHR3byBwb3NzaWJsZSBvcmllbnRhdGlvbnMgKGluIHRoaXMgZGlhZ3JhbSwgdGhhdCB3b3VsZCBhbW91bnQgdG8gdHdvIHdheXMgb2YgZmFjaW5nIG5vcnRoIG9yIHNvdXRoKS4gVGhlIG51bWJlciBvZiBwb3NzaWJsZSBhcnJhbmdlbWVudHMgaXMgdHdvIHRvIHRoZSBudW1iZXIgb2YgcGFpcnMgKGluIHRoaXMgY2FzZSwgdHdvIHNxdWFyZWQgPSA0IHBvc3NpYmxlIGNvbWJpbmF0aW9ucy4=

Cg==

[Qq]

[q] In an organism with six chromosomes, or three homologous pairs (as shown in this diagram) how many combinations of maternal and paternal chromosomes can occur in the gametes?

[c]IDM=[Qq]

[c]IDQ=[Qq]

[c]ID g=[Qq]

[c]IDE2[Qq]

[f]IE5vLiBFYWNoIG9mIHRoZSBob21vbG9nb3VzIHBhaXJzIHdpbGwgaGF2ZSB0d28gcG9zc2libGUgb3JpZW50YXRpb25zIG9yIHdheXMgb2YgbGluaW5nIHVwLCBkdXJpbmcgbWV0YXBoYXNlLiBUaGUgbnVtYmVyIG9mIHBvc3NpYmxlIGFycmFuZ2VtZW50cyBpcyB0d28gdG8gdGhlIG51bWJlciBvZiBwYWlycyAoaW4gdGhpcyBjYXNlLCB0aHJlZSkuIFNvIHRoZSBwb3NzaWJsZSBudW1iZXIgb2YgY29tYmluYXRpb25zIGlzIHR3byB0byB0aGUgM3JkIHBvd2VyLg==[Qq]

[f]IFllcy4gRWFjaCBvZiB0aGUgaG9tb2xvZ291cyBwYWlycyB3aWxsIGhhdmUgdHdvIHBvc3NpYmxlIG9yaWVudGF0aW9ucyBvciB3YXlzIG9mIGxpbmluZyB1cCBkdXJpbmcgbWV0YXBoYXNlLiBUaGUgbnVtYmVyIG9mIHBvc3NpYmxlIGFycmFuZ2VtZW50cyBpcyB0d28gdG8gdGhlIG51bWJlciBvZiBwYWlycyAoaW4gdGhpcyBjYXNlLCB0aHJlZSkuIFNvIHRoZSBwb3NzaWJsZSBudW1iZXIgb2YgY29tYmluYXRpb25zIGlzIHR3byB0byB0aGUgM3JkIHBvd2VyLiBUaGF0IGVxdWFscyA4IHBvc3NpYmxlIGNvbWJpbmF0aW9ucy4=[Qq]

Cg==

[Qq]

[q] In an organism with 46 chromosomes, or 23 homologous pairs (as shown in this diagram) how many combinations of maternal and paternal chromosomes can occur in the gametes?

[c]IDIz[Qq]

[c]IDQ2[Qq]

[c]IDUyOSAod2hpY2ggaXMgZXF1YWwgdG8gMjMgc3F1YXJlZCk=[Qq]

[c]IG92ZXIgOC BtaWxsaW9u[Qq]

[f]IE5vLiBFYWNoIG9mIHRoZSBob21vbG9nb3VzIHBhaXJzIHdpbGwgaGF2ZSB0d28gcG9zc2libGUgb3JpZW50YXRpb25zIG9yIHdheXMgb2YgbGluaW5nIHVwLCBkdXJpbmcgbWV0YXBoYXNlLiBUaGUgbnVtYmVyIG9mIHBvc3NpYmxlIGFycmFuZ2VtZW50cyBpcyB0d28gdG8gdGhlIG51bWJlciBvZiBwYWlycyAoaW4gdGhpcyBjYXNlLCAyMykuIFNvIGl04oCZcyBhIHZlcnkgYmlnIG51bWJlci4gUmVtZW1iZXIgdGhhdCB0aGUgbmV4dCB0aW1lIHlvdSBzZWUgdGhpcyBxdWVzdGlvbi4=[Qq]

[f]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[Qq]

[f]IFllcy4gRWFjaCBvZiB0aGUgaG9tb2xvZ291cyBwYWlycyB3aWxsIGhhdmUgdHdvIHBvc3NpYmxlIG9yaWVudGF0aW9ucyBvciB3YXlzIG9mIGxpbmluZyB1cCwgZHVyaW5nIG1ldGFwaGFzZS4gVGhlIG51bWJlciBvZiBwb3NzaWJsZSBhcnJhbmdlbWVudHMgaXMgdHdvIHRvIHRoZSBudW1iZXIgb2YgcGFpcnMgKGluIHRoaXMgY2FzZSwgMjMpLiBUaGUgYWN0dWFsIG51bWJlciBpcyA4LDM4OCw2MDgu[Qq]

[x]
[restart]

[/qwiz]