Please, could you write just 2-3 sentences (for each) to describe the following quotations from Judith Butler's Gender Trouble: 1. ”The deconstruction of identity is not the deconstruction of politics." (Conclusion, Page 203) 2. “To operate within the matrix of power is not the same as to replicate uncritically relations of domination.” (Chapter 1, Page 42) 3. ”The straight mind continues to affirm that incest, and not homosexuality represents its major interdiction. Thus, when thought by the straight mind, homosexuality is nothing but heterosexuality." - Monique Wittig, The Straight Mind (Chapter 2, Page 47) 4. “…laughter emerges in the realization that all along the original was derived.” (Chapter 3, Page 189) 5. ”But how does a woman 'appear' to be the Phallus, the lack that embodies and affirms the Phallus? According to Lacan, this is done through masquerade, the effect of a melancholy that is essential to the feminine position as such." (Chapter 2, Page 62) 6. “If Lacan presumes that female homosexuality issues from a disappointed heterosexuality, as observation is said to show, could it not be equally clear to the observer that heterosexuality issues from a disappointed homosexuality?” (Chapter 2, Pages 66-67) 7. “When we consider gender identity as a melancholic structure, it makes sense to choose “incorporation” as the manner by which that identification is accomplished.” (Chapter 2, Page 93)

These quotes all revolve around the central concept of Judith Butler's 1990 book Gender Trouble: Feminism and the Subversion of Identity. The main idea of the book is that gender is a social construct. Let's go through each of these seven quotes and talk a bit about what Butler is saying.
1. ”The deconstruction of identity is not the deconstruction of politics."
Here, Butler is preemptively addressing her own critics. Her book is about taking apart (or taking down) traditional ideas about identity—what is gender, and how important is it to one's identity? Talking about this subject, she argues here, does not represent a larger attempt to deconstruct the whole political system. A conversation about individual identity is related to, but does not equate with, a conversation about political structure.
2. “To operate within the matrix of power is not the same as to replicate uncritically relations of domination.”
Again, Butler is drawing a line here, establishing a difference between two situations that can mistakenly be seen as equal. "Replicating uncritically" within a long-held structure of domination (i.e., in which women are inferior to men) is to maintain a status quo, and in Butler's view, it's lazy. This is not the same, she argues, as operating within a matrix of power—you, as an individual, can't change the world around you, but you can change the way you function within it and which decisions you make.
3. ”The straight mind continues to affirm that incest, and not homosexuality, represents its major interdiction. Thus, when thought by the straight mind, homosexuality is nothing but heterosexuality." - Monique Wittig
Here, via a quote by French feminist theorist Wittig, Butler is discussing the traditional hierarchy of prohibited behaviors or sins. In the "straight" view of the world, incest is worse (much worse) than homosexuality. Being gay isn't that bad, in other words, compared to the unspeakable act of committing incest.
4. “…laughter emerges in the realization that all along the original was derived.”
This quote probably needs to be seen in its larger context:

The loss of the sense of the normal can be its own occasion for laughter, especially when the normal, the original is revealed to be a copy, and an inevitably failed one, an ideal that no one can embody. In this sense laughter emerges in the realization that all along the original was derived.

Butler's discussion of gender has a lot to do with social norms. Here, she's saying that even what we consider to be "normal" is just a copy of an impossible ideal. There is no "normal"—there is only the normal that we're conditioned to think is best.
5. ”But how does a woman 'appear' to be the Phallus, the lack that embodies and affirms the Phallus? According to Lacan, this is done through masquerade, the effect of a melancholy that is essential to the feminine position as such."
Butler is referring to French philosopher Jacques Lacan, who was interested in the subject of a phallus. In Lacanian discourse, the penis is a biological organ, while the phallus is symbolic in the realm of fantasy, desire, and sexual identity. A phallus wouldn't play such an important role if it didn't have its reverse ("the lack") represented by female sexual anatomy. It's this lack that gives the phallus its significance.
6. “If Lacan presumes that female homosexuality issues from a disappointed heterosexuality, as observation is said to show, could it not be equally clear to the observer that heterosexuality issues from a disappointed homosexuality?”
See above (#5) for a bit about Lacan and his philosophy regarding the phallus and its reverse, the feminine "lack." His presumption that women must be disappointed/melancholy because of their role in this equation, Butler argues, could be turned on its head—if some women turn to homosexuality because of their so-called "disappointment," isn't it also possible that heterosexual relationships stem out of a disappointment in the homosexual relationship? (This is a little tough to get your head around, I admit. See the link below to more on Lacan's philosophy.)
7. “When we consider gender identity as a melancholic structure, it makes sense to choose “incorporation” as the manner by which that identification is accomplished.”
Returning to Lacan's notion (see above) that female sexuality is somehow defined by disappointment or melancholy, Butler says that incorporation, or joining a group, is the way that gender identity should ideally be defined. I am not born into a gender: I choose it, I choose to identify with a group that I feel I am a part of. Gender can not be assigned to me.