All language subtitles for 67031x_MH_Gene_Function_01_Studying_Functions_v1-en

MICHAEL HEMANN: Last time we talked about the gene

as a structural unit, a sequence of DNA.

But that idea of a gene, that concept

really came only after the identification

of the structure of DNA and the ability to sequence DNA.

But in fact, the basic concepts of modern genetics were--

preceded that discovery by about 100 years

through the work of Gregor Mendel, which

was later rediscovered at the turn of the 19th

to the 20th century.

And Gregor Mendel and later geneticists

postulated that the gene was probably a structural unit,

it was a physical thing.

But again, they didn't know what that physical thing was.

What they were really doing is they were following function

from one generation to the next.

They were following phenotype from one generation

to the next.

And really the foundation of all modern genetics

occurred prior to even understanding anything

about the physical characteristics of a gene.

And so what we're going to talk about for the next number

of lectures is essentially what we

can learn about genes and inheritance

if we know nothing about the physical structure of the gene

itself.

And really, it's a great deal.

In fact, even today, a lot of what

we know about heredity and inheritance

comes without knowing anything about the specifics of a gene

sequence, or a new mutation, or an alteration in a target

protein.

And so in the context of this course,

we're going to talk about a lot of different model organisms.

A lot of these have very interesting biologies,

but I think you want to bear in mind that the specific biology

of these organisms is generally not what we're interested in.

So certainly things like yeast and bacteria

are important pathogens.

They do important things for us.

But in general, we're using these organisms

to tell us, or illustrate really fundamental aspects

of genetics, issues that these organisms are really

well placed to learn from, or to point out.

So we're using them as examples.

But the basic principles are conserved from yeast, to us,

to the Jonas Brothers.

We are all essentially governed by a lot

of the same biological principles.

And so in thinking about the examples

that I bring up, remember that these things aren't

specific to flies, they're not specific to yeast.

These are particular tools that we use

and systems that we use to explore this kind of biology.

So if you're questioning the broader relevance

or how they translate to one another, please let me know.

Because again, the core principles are conserved.