In beetles body color is determined by an autosomal gene...

. In beetles, body color is determined by an autosomal gene with two alleles, where B is incompletely dominant to b such that BB beetles are black, Bb beetles are brown and bb beetles are yellow. An X-linked gene determines body size, with normal size (M) completely dominant to miniature body size (m). Male beetles are heterogametic (XY). Pure-breeding female beetles with black miniature sized bodies were crossed to male beetles with yellow normal sized bodies to generate F1 progeny. F1 males and females were then mated to produce an F2 generation. Based on this information, which of the following statements is FALSE? A. All F1 males are brown with miniature bodies. B. 1/16 of the F2 progeny will be females with yellow miniature bodies. C. ¼ of the F2 progeny have brown, normal sized bodies. D. All F1 females are brown with normal size bodies. E. ¾ of the F2 progeny have black body color.

Transcript

00:02 In order to answer this question, let's talk about inheritance.

00:05 It says, in vitals, body color is determined by an autosomal gene with two adiles.

00:09 Whatever is incompletely dominant to recessive b.

00:12 It means when you get a homocygous dominant, you get black.

00:19 When you get the homocyluses, recessive, you're going to get yellow.

00:24 And when you get the heterocygose, you get brown.

00:30 Then it says an excellent gene that reminds body size.

00:34 It means when you have the homozygose dog.

00:37 For the heterosophagus like this, they're going to get normal size.

00:46 The same for males, you have this.

00:49 Okay, it's going to be normal size, male.

00:52 And the homozygos recessive here is going to code for miniature body size, miniature body size, okay? and here for the male is like this.

01:09 Then it says, male beetles are heterogametic.

01:16 Pure breeding female beetles with black miniature size body.

01:21 Remember that purebri breeding means homicides.

01:24 So it says poor breeding female beetles with black miniature.

01:29 It means they are black.

01:30 So they are homozygosominant.

01:34 A miniature is homoseogicicase.

01:39 Like this, okay? we're crossed two male beetles with yellow normal size bodies.

01:47 So versus males are x, y, and these males are yellow.

01:55 It means they are homozygot excessive, yellow, a normal sized body.

02:02 It means normal size is like this.

02:05 This is the only possibility, dominant m.

02:08 Now it's just to generate an f1 progeny.

02:11 So let's find that i'm mix first.

02:15 You get the gamut by mixing each of these b alleles with each of these x alleles and the same here.

02:18 So the only possible commit here is dominant b, and recessive.

02:22 M, and here you have two gametes that are this and this.

02:29 So if you make your pan in a square, it's just completed here, you have here this, you have heterocygous, and here you have heterocygous, and here you have heterocygous and like this, okay? i'm sorry but i didn't have enough space here.

02:50 So this is your f1, these two organisms here.

02:53 Now, it's just, f1 males and females were then made it to produce an effect, 2 generation.

02:58 So you are going to cross this one with this one, okay? based on this information, which of the following statements is false? it says, all f1 males are brown with miniature bodies.

03:09 So the f1, this is the f1.

03:12 The male, look at the male.

03:13 What is the phenotype for this male? it's dominant and here it is recessive.

03:17 So it is, well, it is heterocygous, it means it is brown and also a minetro.

03:25 Okay, so option a is, option a is.

03:28 Is true.

03:29 So it is not the answer because we're looking for the false.

03:31 Okay.

03:32 Option b says one 16th of the f2 prergeny will be females with yellow miniature bodies.

03:41 So first let's set our panel square, okay? it is going to be a large panel and square, but actually in this case, as they are giving us a proportion or a phenotype, specifically we can do something here.

03:55 We can, well, the work course is going to be this, right? hitro cygios b.

04:01 Hiterozygos m, and here you have heterocygous b and recessive m, like this.

04:06 Okay, so you're going to cross in this way.

04:12 This hitrocygos with this hitrocygos and this one with this one.

04:14 So you're going to have the following.

04:21 Mosygo's, hitrocygos, hitrocygos, homo, sego, decessive.

04:24 Here you have this, excessive, heterocyboceph, heterocyboes, heterocytes, commasive, this, and this...