Prezygotic isolating mechanisms prevent hybrid of fspring...

Name: Problem 3, Chapter 13: Biology Now
Uploaded: 2021-09-09T18:32:04-08:00
Duration: 3 min 4 s
Channel: Briana De La Torre
Description: Prezygotic isolating mechanisms prevent hybrid of fspring from occurring between species because (a) the resulting offspring are not fertile and cannot reproduce. (b) the egg and sperm fuse and form a zygote, but it does not survive. (c) the egg and sperm do not ever meet or, if they do, cannot fuse to form a zygote. (d) all of the above

Prezygotic isolating mechanisms prevent hybrid of fspring from occurring between species because (a) the resulting offspring are not fertile and cannot reproduce. (b) the egg and sperm fuse and form a zygote, but it does not survive. (c) the egg and sperm do not ever meet or, if they do, cannot fuse to form a zygote. (d) all of the above

Prezygotic isolating mechanisms prevent hybrid of fspring from occurring between species because
(a) the resulting offspring are not fertile and cannot reproduce.
(b) the egg and sperm fuse and form a zygote, but it does not survive.
(c) the egg and sperm do not ever meet or, if they do, cannot fuse to form a zygote.
(d) all of the above

Key Concepts

Speciation

Speciation is the evolutionary process through which new species arise, typically through the accumulation of genetic differences and the development of reproductive isolating mechanisms. By preventing interbreeding, these mechanisms ensure that populations diverge over time into distinct species.

Reproductive Isolation

Reproductive isolation encompasses all mechanisms, both before and after fertilization, that reduce or eliminate gene flow between populations. It is a critical concept in evolutionary biology, as it maintains species boundaries and facilitates the process of speciation.

Prezygotic Isolating Mechanisms

Prezygotic isolating mechanisms are barriers that operate before fertilization occurs. They include behavioral, temporal, mechanical, and gametic isolations that prevent mating or hinder the fusion of gametes between members of different species, thereby stopping hybrid zygote formation altogether.

Transcript

00:02 Reproductive barriers are going to be when there's two species that are reproductively isolated from one another.

00:09 Now that can be categorized into two different areas.

00:14 So first we're going to add that here, so i'm going to go rb for reproductive barriers, and we're going to divide that into the two categories.

00:24 First one is going to be pre -zygotic, and then the other one is post -zygotic.

00:32 So just like it's prefix, pre -meaning before and post -meaning before, after.

00:38 So prezygotic is going to be before the zygo is formed in reproduction, and then post -zygotic is going to be after the zygoe has been formed, just so we know the difference between them there.

00:50 Now, under pre -zigotic, there's going to be different types of isolation that are going to be coming from here.

00:55 So starting with pre -right here, we're going to add some of those here.

01:01 So first we have ecological isolation, abbreviating that with ei.

01:07 So this is where there's two species that breed in different portions of their habitat.

01:12 So in different areas of where they're living at and in different types of seasons or different times of the day.

01:20 Then we have behavioral isolation.

01:25 This is where there's two species that respond badly to one another.

01:31 They just don't get along.

01:34 We then have mechanical isolation...