Genetics Past Paper PDF

Genetics By : team 3 Supervisor :Dr Ali Amen Team Rahma Reda Amal Elsaid Memb Heraa Emad Yasmine Osama ers Basmala Ehab  A gene is like a recipe for a specific what is a protein. It's a small piece of DNA that gene? tells our cells how to build th...

Genetics By : team 3 Supervisor :Dr Ali Amen Team Rahma Reda Amal Elsaid Memb Heraa Emad Yasmine Osama ers Basmala Ehab  A gene is like a recipe for a specific what is a protein. It's a small piece of DNA that gene? tells our cells how to build that protein. Proteins are the building blocks of our bodies and help us grow, repair, and function.  The Human Genome Project The Human Genome Project is an international effort to clone and sequence the entire human genome. This audacious project, estimated to cost about $200 million per year and take 15 years to complete, promises to be one of the most exciting and revolutionary scientific endeavors ever devised by humanity. By sequencing an estimated 3 billion base pairs of the haploid human genome and more than 30,000 genes , The Human Genome Project is an ambitious research effort that aims to decode the chemical makeup of the entire human genetic code (i.e., the genome). The core work of the project is to develop three research tools that will allow scientists to identify genes involved in rare and common diseases..  The Open Reading Frame (ORF) is a part of a DNA sequence that can be Open Reading translated into a protein. It consists of a sequence of nucleotides that starts Frame with a start codon (usually AUG) and ends with a stop codon (such as UAA, UAG, or UGA). Open Reading Frames are important for identifying genes and their functions, as they reflect the genetic information needed for protein synthesis. TATA Boxes TATA boxes are short sequences of nucleotides (the building blocks of DNA) typically consisting of a specific sequence of nucleotides (usually TATA, hence the name). These sequences are found in the promoter regions of many eukaryotic genes, which are genes found in organisms with a nucleus in their cells. What is the Role of TATA Boxes ? TATA boxes play a crucial role in initiating the process of gene transcription. Transcription is the process by which the genetic information contained in DNA is copied into another molecule called RNA. This new RNA molecule carries the code necessary for protein synthesis. * Binding Site: TATA boxes serve as binding sites for proteins called transcription factors. * Start Site Determination: Gene Expression Regulation: Stop Codons What is a stop codon? A stop codon is a specific sequence of three nucleotides in messenger RNA (mRNA) that signals the end of the protein synthesis process. In simpler terms, it's a "stop sign" that tells the cell it has finished building the required protein. What are the functions of stop codons? * 1-Terminating Translation: 2-Ensuring Protein Accuracy *3- Gene Expression Regulation Types of Stop Codons: There are three main types of stop codons: UAA, UAG, and UGA. Each signals the end of translation. multigene famil y Idea: The parents are originally a unit of organization and my tags. Their associations are closely related, and they are groups of causes that started from a single gene through the strategy of multiplying their number. Share in these things a high degree of similarity in details and parts what are the similar related functions. How it happens: a number of genomic and evolutionary mechanisms have been discovered that shape the development, structure, and organization of multigene families. While gene duplication is the fundamental process, other phenomena such as : Pseudogene formation, gene loss, recombination, and natural selection have been shown to act to varying degrees to shape the evolution of gene families. Examples of multiple gene families: Hemoglobin genes: Antibody genes: Histone genes:  Why study gene families? Understanding evolution: Studying gene families helps us understand how organisms evolve and adapt to their environments. Medical discoveries: Studying these families can help us develop new treatments for genetic diseases. Genetic improvement: Information about gene families can be used to improve crops and animals.  Genetic 1. Codons code The genetic code is read in three-letter "words" called codons. Each codon is a sequence of three nucleotide bases (A, U, G, C in RNA; A, T, G, C in DNA). 2. Amino Acids and Codons Each codon specifies a particular amino acid or a stop signal for protein synthesis. 61 codons code for the 20 standard amino acids, meaning multiple codons can specify the same amino acid. This feature is known as redundancy or degeneracy of the genetic code. Stop codons UAA , UGA , UAG Start Codon AUG  Mitochondrial genes 1. Encoding for Proteins Involved in Respiration: Mitochondrial genes primarily encode proteins essential for oxidative phosphorylation, the process by which cells produce ATP (energy). This includes genes for enzymes in the electron transport chain and ATP synthase complex. 2. Reduced Genome: The mitochondrial genome is much smaller than the nuclear genome, with humans typically having only 37 genes in their mtDNA. These genes are highly conserved and perform essential functions for cellular respiration. 3. tRNA and rRNA Genes: Mitochondrial DNA also encodes tRNAs and rRNAs, necessary for protein synthesis within the mitochondria. What is EXAMPLE: gene expression? Gene expression is the process by which the information stored in a gene is used to create a functional product, usually a protein. DNA contains the instructions for making these proteins. When a cell needs a specific protein, it reads the corresponding gene and follows the instructions to build the protein. This process is essential for all living organisms to grow, function, and adapt to their environment.  Exons Intron EXAMPLE: Introns are segments of a gene that do not code for Exons are the coding sections of a gene proteins. During the initial transcription process, they that are transcribed into RNA and eventually are copied into pre-messenger RNA (pre-mRNA) but are translated into proteins. Unlike introns (non- removed during RNA splicing. coding sequences), exons are expressed Functions and Significance: and form the final mature mRNA molecule. Regulatory roles: Although introns are non-coding, they Alternative splicing: play important regulatory roles. They can influence the Exons can be combined in different ways timing of gene expression and allow for different during alternative splicing, which allows a regulatory mechanisms that impact gene function. single gene to produce multiple protein Alternative splicing: Introns enable alternative splicing, isoforms. This process contributes to where a single gene can lead to different protein protein diversity and is a significant products by varying the combination of exons included regulatory mechanism in eukaryotes. - Depending on how the exons are in the final mRNA. This increases the diversity of proteins arranged or omitted, the final mRNA can an organism can produce from a limited number of code for proteins with different structures genes. and functions. Gene evolution: Introns may facilitate the evolution of new genes through processes. Thank You