Help with lesson plan

[Don]

Next week, I'm teaching genetics and other reptile related subjects to every 7th grade student at a local school. We did this last year and when I talked about recessive, co-dominate and dominate genes, the kids were lost. They talked in terms of little "t" and big "T". However, they did understand me talking about heterozygous and homozygous morphs.

I'm a business major MBA, not a biologist and am a little surprised that the school keeps calling me back to teach something that was not my major. We spend two full days at the school and teach around eight 90 minute classes. I want to do a better job of making it relevant to the kids. Can anyone direct me to a genetics lesson that correlates big T little t to our BP morphs? I've been looking and don't see anything that I can use.

Thanks

Don

[Mike41793]

Wait... What did they and what didnt they understand...?

[GoFride]

Are you doing Punnet squares, with Big T (Tall) and little t (dwarf)?

[ewaldrep]

what is the familiarity the students have with genetics? If you start talking about dominant, co-dominant and recessivge genes to a group of people, mush less kids, that don't have a basic understanding of genetics they they will be lost. I would suggest starting with lots of puctures of simple things such as pea plants to introduce the topic, like a basic biology text would and then progress from there. You can also use examples such as eye color or blood types too. Good luck and let us know how it turns out.

[TheSnakeGeek]

Are you doing Punnet squares, with Big T (Tall) and little t (dwarf)?

this. this was how i learned basic genetics in middle school (or maybe high school. don't remember). showing how each parent only passes on one gene. the punnet squares are where i'd start before anything else.

[Don]

Wait... What did they and what didnt they understand...?

They understood hets and visuals (in our hobby terms). They did not understand recessives, but the teacher stepped in and talked about big T and little t. I'm looking for something to bring all of our terms together so I can say recessive is tT, or whatever it is.

Like I said, I'm a business major and my basic genetics class in school was in the 1970's. I've done a lot of self study's since then, but I learned scientific terms, not little letter big letter. I'm just trying to reconcile the terms so the lesson plan has meaning for them. I understand what I'm doing in my breeding program, just need to translate to their terms.

[Mike41793]

a recessive would be tt

Het x Het would be:
Tt x Tt and result in:
25%TT (normal)
50% Tt (hets)
25% tt (visual recessives)

Is that what you mean...?

Imo itd be easier to use Nn x Nn for normals. Idk where the Tt came from lol

[Don]

this. this was how i learned basic genetics in middle school (or maybe high school. don't remember). showing how each parent only passes on one gene. the punnet squares are where i'd start before anything else.

Yup, that is what I'm trying to get to. How does the letters relate to recessive, dominate and co-dominate genes.

Guys, I'm over 50 years old and like I said, my last formal lesson in genetics was in the 70's. I can put together the odds for double recessives and many combos of BP genes, but can't translate it to big and little letters.

[BHReptiles]

If they understand "big T" and "little t", use a punnet square when talking about the recessives. For albinos, for example, show them this table:

PARENTS (albino x het albino)	a	a
A	Aa - het albino	Aa - het albino
a	aa - albino	aa - albino

You can obviously change up the genetics to do something with pieds.

As for the actual letters, they are interchangeable. You usually use a letter that's in the genes you want to work with. So for albinos, you use the letter "a". For pieds, you might use the letter "p". Just use letters where the upper and lower case look different from each other. Don't use something like Cc or Ss. It can get confusing if you are manually writing it out.

The upper case letters represents the non-recessive gene or the "wildtype" gene. The lower case letter represents anything recessive.

[tlich]

Not sure if this will help?

http://www.arbreptiles.com/genetics101.shtml