Sex Determination Mechanism

Finalization of sex at the time of zygote formation is called sex determination.
Two types of chromosomes are present in individuals – sex chromosomes (which determine the sex of individuals) and autosomes.

1. XX-XY TYPE

Seen in many insects and mammals including humans, Drosophila melanogaster. Males have X and Y chromosomes along with autosomes [A] and females have a pair of X chromosomes.

2. XX-XO TYPE

Seen in grasshopper. Males have only one X chromosomes besides autosomes and females have a pair of X chromosomes.

3. ZZ-ZW TYPE

Seen in birds, fowl and fishes. Females have one Z and one W chromosomes whereas males have a pair of Z chromosomes.

4. XX-XY TYPE

Seen in cockroaches. Females have only one Z chromosomes besides autosomes and males have a pair of Z chromosomes.

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Genetic Mutations

GENETIC MUTATIONS Genetic mutations are spontaneous changes occurring in the genetic material, (DNA) of an individual. Mutations can be passed to the next generations or may not, depending upon the type of cell in which they occur. They can be harmful, beneficial or even neutral. Usually these are caused naturally but they can be caused by harmful radiations or chemicals or drugs etc. Somatic cell’s mutations do not pass to the offspring. While the mutations in germ line cells are hereditary. The term mutation was given by Devries in 1909. Types of Mutations Two most basic categories of mutations are: Point mutations These mutations are those occurring only at certain points in chromosomes or the genes if it. For example, insertion, deletion etc. Chromosomal mutation More sever class of mutations is chromosomal mutations. It includes deletion of one or set of chromosome, or may be more number of chromosomes is present in genome than normal numbers....

Genomics_command_line_quiz1 For all projects, you may use your own Unix-based system and, where applicable, ensure that you are running the version of the software specified in the assignments. Alternatively, you may use the VMBox virtual machine environment provided with the course materials. Instructions on how to download and use the environment can be found on the course web site. For the following questions, refer to the class workflow and use the data in the Online materials (‘gencommand_proj1_data.tar.gz’) to answer the questions. Assume you sequenced and assembled the genome of Malus domestica (apple), and performed gene annotation. You then collected samples and ran RNA-seq experiments to determine sets of genes that are expressed in the various tissues. This information was stored, respectively, in the following files: “apple.genome”, “apple.genes”, “apple.condition{A,B,C}”. NOTE: The apple genome and the apple gene annotations for this project were extracted from the Ro...

DECODE The Script of LIFE

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