Animal Biology (L2) PDF

Animal Biology (L2)  2- Lipids 2- ‫اﻟﺪﻫﻮن‬ -Lipids are diverse in structure and function, but they ‫ إﻻ أﻧﻬﺎ ﺗﺸﺘﺮك ﻓﻲ ﺳﻤﺔ ﻣﺸﺘﺮﻛﺔ‬،‫ ـ ﺗﺘﻨﻮع اﻟﺪﻫﻮن ﻓﻲ ﺑﻨﻴﺘﻬﺎ ووﻇﻴﻔﺘﻬﺎ‬: have a common...

Animal Biology (L2)  2- Lipids 2- ‫اﻟﺪﻫﻮن‬ -Lipids are diverse in structure and function, but they ‫ إﻻ أﻧﻬﺎ ﺗﺸﺘﺮك ﻓﻲ ﺳﻤﺔ ﻣﺸﺘﺮﻛﺔ‬،‫ ـ ﺗﺘﻨﻮع اﻟﺪﻫﻮن ﻓﻲ ﺑﻨﻴﺘﻬﺎ ووﻇﻴﻔﺘﻬﺎ‬: have a common characteristic: They do not dissolve ‫ وﻫﻲ أﻧﻬﺎ ﻻ ﺗﺬوب ﻓﻲ اﻟﻤﺎء‬. in water. -Their low solubility in water is due to an absence of ‫ـ إن اﻧﺨﻔﺎض ﻗﺎﺑﻠﻴﺘﻬﺎ ﻟﻠﺬوﺑﺎن ﻓﻲ اﻟﻤﺎء ﻳﺮﺟﻊ إﻟﻰ ﻏﻴﺎب اﻟﻤﺠﻤﻮﻋﺎت اﻟﻘﻄﺒﻴﺔ‬ hydrophilic polar groups. ‫ اﻟﻤﺤﺒﺔ ﻟﻠﻤﺎء‬. -They contain little oxygen and consist mostly of ‫ـ ﺗﺤﺘﻮي ﻋﻠﻰ ﻛﻤﻴﺔ ﻗﻠﻴﻠﺔ ﻣﻦ اﻷﻛﺴﺠﻴﻦ وﺗﺘﻜﻮن ﻓﻲ اﻟﻐﺎﻟﺐ ﻣﻦ ذرات‬ carbon ‫اﻟﻜﺮﺑﻮن واﻟﻬﻴﺪروﺟﻴﻦ‬. and hydrogen atoms. - Lipids contain more energy per gram than other ‫ ـ ﺗﺤﺘﻮي اﻟﺪﻫﻮن ﻋﻠﻰ ﻃﺎﻗﺔ أﻛﺒﺮ ﻟﻜﻞ ﺟﺮام ﻣﻦ اﻟﺠﺰﻳﺌﺎت اﻟﺒﻴﻮﻟﻮﺟﻴﺔ اﻷﺧﺮى‬. biological molecules. -Therefore, fats in animals and oils in plants function - ‫ ﺗﻌﻤﻞ اﻟﺪﻫﻮن ﻓﻲ اﻟﺤﻴﻮاﻧﺎت واﻟﺰﻳﻮت ﻓﻲ اﻟﻨﺒﺎﺗﺎت ﺑﺸﻜﻞ ﺟﻴﺪ‬،‫ﻟﺬﻟﻚ‬ well as energy storage molecules. ‫ﻛﺠﺰﻳﺌﺎت ﺗﺨﺰﻳﻦ ﻟﻠﻄﺎﻗﺔ‬. -Steroids are a large class of lipids that includes, -،‫ ﻣﻦ ﺑﻴﻦ ﺟﺰﻳﺌﺎت أﺧﺮى‬،‫اﻟﺴﺘﻴﺮوﻳﺪات ﻫﻲ ﻓﺌﺔ ﻛﺒﻴﺮة ﻣﻦ اﻟﺪﻫﻮن اﻟﺘﻲ ﺗﺸﻤﻞ‬ among other molecules, the sex hormones. ‫اﻟﻬﺮﻣﻮﻧﺎت اﻟﺠﻨﺴﻴﺔ‬. -Phospholipids have a phosphate group and are the - ‫ﺗﺤﺘﻮي اﻟﻔﻮﺳﻔﻮﻟﻴﺒﻴﺪات ﻋﻠﻰ ﻣﺠﻤﻮﻋﺔ ﻓﻮﺳﻔﺎت وﻫﻲ اﻟﻤﻜﻮﻧﺎت اﻷﺳﺎﺳﻴﺔ‬ primary components of the plasma membranes in ‫ﻟﻠﻐﺸﺎء اﻟﺒﻼزﻣﻲ ﻓﻲ اﻟﺨﻼﻳﺎ‬. cells. 3-Proteins 3-‫اﻟﺒﺮوﺗﻴﻨﺎت‬ -Proteins are macromolecules with amino acid -‫اﻟﺒﺮوﺗﻴﻨﺎت ﻋﺒﺎرة ﻋﻦ ﺟﺰﻳﺌﺎت ﻛﺒﻴﺮة ﺗﺤﺘﻮي ﻋﻠﻰ وﺣﺪات ﻓﺮﻋﻴﺔ ﻣﻦ‬ subunits. ‫اﻷﺣﻤﺎض اﻷﻣﻴﻨﻴﺔ‬. -The central carbon atom in an amino acid bonds to a - ‫ﺗﺮﺗﺒﻂ ذرة اﻟﻜﺮﺑﻮن اﻟﻤﺮﻛﺰﻳﺔ ﻓﻲ اﻷﺣﻤﺎض اﻷﻣﻴﻨﻴﺔ ﺑﺬرة اﻟﻬﻴﺪروﺟﻴﻦ‬ hydrogen atom and to three other groups of atoms. ‫ وﺛﻼث ﻣﺠﻤﻮﻋﺎت أﺧﺮى ﻣﻦ اﻟﺬرات‬: -The name amino acid is - because one of these groups NH2- ‫ اﺳﻢ ﺣﻤﺾ أﻣﻴﻨﻲ ﻣﻨﺎﺳﺐ ﻷن إﺣﺪى ﻫﺬه اﻟﻤﺠﻤﻮﻋﺎت ﻫﻲ‬- is an -NH2 (amino group) and another is a -COOH ).‫ ﺣﻤﺾ‬،‫ )ﻣﺠﻤﻮﻋﺔ ﻛﺮﺑﻮﻛﺴﻴﻞ‬COOH- ‫)ﻣﺠﻤﻮﻋﺔ أﻣﻴﻨﻴﺔ( واﻷﺧﺮى ﻫﻲ‬ (carboxyl group, an acid). -The third group is the R group for ).1 ‫ ﻟﻠﺤﻤﺾ اﻷﻣﻴﻨﻲ )اﻟﺸﻜﻞ‬R ‫ اﻟﻤﺠﻤﻮﻋﺔ اﻟﺜﺎﻟﺜﺔ ﻫﻲ اﻟﻤﺠﻤﻮﻋﺔ‬- an amino acid (Figure 1). Figure 1: The structure of the amino acid -The covalent bond between two amino acids is -‫اﻟﺮاﺑﻄﺔ اﻟﺘﺴﺎﻫﻤﻴﺔ ﺑﻴﻦ ﺣﻤﻀﻴﻦ أﻣﻴﻨﻴﻴﻦ ﺗﺴﻤﻰ راﺑﻄﺔ ﺑﺒﺘﻴﺪﻳﺔ‬. called a peptide bond. -When three or more amino acids are linked by ،‫ـ ﻋﻨﺪﻣﺎ ﺗﺮﺗﺒﻂ ﺛﻼﺛﺔ أو أﻛﺜﺮ ﻣﻦ اﻷﺣﻤﺎض اﻷﻣﻴﻨﻴﺔ ﺑﻮاﺳﻄﺔ رواﺑﻂ ﺑﺒﺘﻴﺪﻳﺔ‬ peptide bonds, the chain that results is called a ‫ﻓﺈن اﻟﺴﻠﺴﻠﺔ اﻟﻨﺎﺗﺠﺔ ﺗﺴﻤﻰ ﺑﻮﻟﻲ ﺑﺒﺘﻴﺪ‬. polypeptide. - Proteins are of primary importance in the structure - ‫ وﻣﻦ ﺑﻴﻦ وﻇﺎﺋﻔﻬﺎ‬.‫اﻟﺒﺮوﺗﻴﻨﺎت ﻟﻬﺎ أﻫﻤﻴﺔ أﺳﺎﺳﻴﺔ ﻓﻲ ﺑﻨﻴﺔ اﻟﺨﻼﻳﺎ ووﻇﻴﻔﺘﻬﺎ‬ and function of cells. Some of their many functions in ‫اﻟﻌﺪﻳﺪة ﻓﻲ اﻟﺒﺸﺮ‬: humans include: 1-Support: Some proteins are structural proteins. 1- ‫ ﻳﺸﻜﻞ‬،‫ ﻋﻠﻰ ﺳﺒﻴﻞ اﻟﻤﺜﺎل‬.‫ ﺑﻌﺾ اﻟﺒﺮوﺗﻴﻨﺎت ﻫﻲ ﺑﺮوﺗﻴﻨﺎت ﺑﻨﻴﻮﻳﺔ‬:‫اﻟﺪﻋﻢ‬ Keratin, for example, makes up hair and nails. ‫ ﻳﻮﻓﺮ اﻟﻜﻮﻻﺟﻴﻦ اﻟﺪﻋﻢ ﻟﻸرﺑﻄﺔ واﻷوﺗﺎر واﻟﺠﻠﺪ‬.‫اﻟﻜﻴﺮاﺗﻴﻦ اﻟﺸﻌﺮ واﻷﻇﺎﻓﺮ‬. Collagen lends support to ligaments, tendons, and skin. 2-Enzymes: Enzymes bring reactants together and 2- ‫ ﺗﻌﻤﻞ اﻹﻧﺰﻳﻤﺎت ﻋﻠﻰ ﺟﻤﻊ اﻟﻤﻮاد اﻟﻤﺘﻔﺎﻋﻠﺔ ﻣﻌً ﺎ وﺑﺎﻟﺘﺎﻟﻲ‬:‫اﻹﻧﺰﻳﻤﺎت‬ thereby speed chemical reactions in cells and only ‫ﺗﺴﺮﻳﻊ اﻟﺘﻔﺎﻋﻼت اﻟﻜﻴﻤﻴﺎﺋﻴﺔ ﻓﻲ اﻟﺨﻼﻳﺎ وﻻ ﺗﻌﻤﻞ إﻻ ﻓﻲ درﺟﺔ ﺣﺮارة اﻟﺠﺴﻢ‬. function at body temperature. 3-Transport: Channel and carrier proteins in the 3- ‫ ﺗﺴﻤﺢ اﻟﺒﺮوﺗﻴﻨﺎت اﻟﻨﺎﻗﻠﺔ واﻟﻘﻨﻮاﺗﻴﺔ ﻓﻲ اﻟﻐﺸﺎء اﻟﺒﻼزﻣﻲ ﻟﻠﻤﻮاد‬:‫اﻟﻨﻘﻞ‬ plasma membrane allow substances to enter and exit ‫ﺑﺎﻟﺪﺧﻮل‬ cells. hemoglobin in red blood cells transports ‫ ﻳﻨﻘﻞ اﻟﻬﻴﻤﻮﺟﻠﻮﺑﻴﻦ ﻓﻲ ﺧﻼﻳﺎ اﻟﺪم اﻟﺤﻤﺮاء‬.‫إﻟﻰ اﻟﺨﻼﻳﺎ واﻟﺨﺮوج ﻣﻨﻬﺎ‬ oxygen. ‫اﻷﻛﺴﺠﻴﻦ‬. 4-Defense: Antibodies are proteins combine with 4- ‫ اﻷﺟﺴﺎم اﻟﻤﻀﺎدة ﻫﻲ ﺑﺮوﺗﻴﻨﺎت ﺗﺘﺤﺪ ﻣﻊ ﻣﻮاد ﻏﺮﻳﺒﺔ ﺗﺴﻤﻰ‬:‫اﻟﺪﻓﺎع‬ foreign substances, called antigens preventing from ‫ ﻣﻤﺎ ﻳﻤﻨﻌﻬﺎ ﻣﻦ ﺗﺪﻣﻴﺮ اﻟﺨﻼﻳﺎ وإزﻋﺎج اﻟﺘﻮازن اﻟﺪاﺧﻠﻲ‬،‫اﻟﻤﺴﺘﻀﺪات‬. destroying cells and upsetting homeostasis. 5-Hormones: Hormones are regulatory proteins. 5- ‫ ﺗﻌﻤﻞ ﻛﺮﺳﻞ ﺑﻴﻦ‬،‫ اﻟﻬﺮﻣﻮﻧﺎت ﻋﺒﺎرة ﻋﻦ ﺑﺮوﺗﻴﻨﺎت ﺗﻨﻈﻴﻤﻴﺔ‬:‫اﻟﻬﺮﻣﻮﻧﺎت‬ They serve as intercellular messengers that influence ‫اﻟﺨﻼﻳﺎ ﺗﺆﺛﺮ ﻋﻠﻰ ﻋﻤﻠﻴﺔ اﻟﺘﻤﺜﻴﻞ اﻟﻐﺬاﺋﻲ ﻟﻠﺨﻼﻳﺎ‬. the metabolism of cells. 6-Motion: The contractile proteins actin and myosin 6- ‫ ﺗﺴﻤﺢ اﻟﺒﺮوﺗﻴﻨﺎت اﻻﻧﻘﺒﺎﺿﻴﺔ اﻷﻛﺘﻴﻦ واﻟﻤﻴﻮﺳﻴﻦ ﻷﺟﺰاء ﻣﻦ‬:‫اﻟﺤﺮﻛﺔ‬ allow parts of cells to move and cause muscles to ‫اﻟﺨﻼﻳﺎ ﺑﺎﻟﺤﺮﻛﺔ وﺗﺴﺒﺐ اﻧﻘﺒﺎض اﻟﻌﻀﻼت ﻣﻤﺎ ﻳﺴﻬﻞ ﺣﺮﻛﺔ اﻟﺤﻴﻮاﻧﺎت‬. contract facilitating the movement of animals. 4-Nucleic Acids 4-‫اﻷﺣﻤﺎض اﻟﻨﻮوﻳﺔ‬ -Nucleic acids , which are polymers of nucleotides, ‫ ﺗﺨﺰن‬،‫ ﻫﻲ ﻋﺒﺎرة ﻋﻦ ﺑﻮﻟﻴﻤﺮات ﻣﻦ اﻟﻨﻴﻮﻛﻠﻴﻮﺗﻴﺪات‬،‫اﻷﺣﻤﺎض اﻟﻨﻮوﻳﺔ‬ store information, include instructions for life. ‫ وﺗﺘﻀﻤﻦ ﺗﻌﻠﻴﻤﺎت ﻟﻠﺤﻴﺎة‬،‫اﻟﻤﻌﻠﻮﻣﺎت‬. -The general structure of a nucleotide is shown in - )2) ‫ﻳﻈﻬﺮ اﻟﻬﻴﻜﻞ اﻟﻌﺎم ﻟﻠﻨﻴﻮﻛﻠﻴﻮﺗﻴﺪات ﻓﻲ اﻟﺸﻜﻞ‬. Figure (2). Figure 2: The general structure of a nucleotide -Two types of nucleic acids (DNA & RNA) are ‫ ﻣﻬﻤﺎن ﻓﻲ ﺗﺨﺰﻳﻦ‬RNA) ‫ و‬DNA ) ‫ـ ﻫﻨﺎك ﻧﻮﻋﺎن ﻣﻦ اﻷﺣﻤﺎض اﻟﻨﻮوﻳﺔ‬ important in the storage and processing of the.‫وﻣﻌﺎﻟﺠﺔ اﻟﻤﻌﻠﻮﻣﺎت اﻟﻮراﺛﻴﺔ‬ genetic information. -DNA (deoxyribonucleic acid) is the type of nucleic ‫اﻟﺤﻤﺾ اﻟﻨﻮوي اﻟﺮﻳﺒﻲ ﻣﻨﻘﻮص اﻷوﻛﺴﺠﻴﻦ( ﻫﻮ ﻧﻮع ﻣﻦ‬- DNA) acid that not only stores information about how to ‫اﻷﺣﻤﺎض اﻟﻨﻮوﻳﺔ اﻟﺘﻲ ﻻ ﺗﺨﺰن اﻟﻤﻌﻠﻮﻣﺎت ﺣﻮل ﻛﻴﻔﻴﺔ ﻧﺴﺦ ﻧﻔﺴﻬﺎ أو‬ copy, or replicate, itself but also specifies the order in ً ‫ ﺑﻞ ﺗﺤﺪد‬،‫ﻣﻀﺎﻋﻔﺔ ﻧﻔﺴﻬﺎ ﻓﺤﺴﺐ‬ ‫أﻳﻀﺎ اﻟﺘﺮﺗﻴﺐ اﻟﺬي ﻳﺠﺐ أن ﺗﺘﺤﺪ ﻓﻴﻪ‬ which amino acids are to be joined to make a protein..‫اﻷﺣﻤﺎض اﻷﻣﻴﻨﻴﺔ ﻟﺘﻜﻮﻳﻦ اﻟﺒﺮوﺗﻴﻦ‬ - Nucleotide Structure - ‫ﺑﻨﻴﺔ اﻟﻨﻮﻛﻠﻴﻮﺗﻴﺪات‬ - Each nucleotide is a molecular complex of three - ‫ﻛﻞ ﻧﻴﻮﻛﻠﻴﻮﺗﻴﺪ ﻋﺒﺎرة ﻋﻦ ﻣﺮﻛﺐ ﺟﺰﻳﺌﻲ ﻣﻦ ﺛﻼﺛﺔ أﻧﻮاع ﻣﻦ ﺟﺰﻳﺌﺎت‬ types of subunit molecules : ‫ وﺳﻜﺮ اﻟﺒﻨﺘﻮز )ﺧﻤﺲ‬،(‫ اﻟﻔﻮﺳﻔﺎت )ﺣﻤﺾ اﻟﻔﻮﺳﻔﻮرﻳﻚ‬:‫اﻟﻮﺣﺪة اﻟﻔﺮﻋﻴﺔ‬ phosphate (phosphoric acid), a pentose (5-carbon) ‫ وﻗﺎﻋﺪة ﺗﺤﺘﻮي ﻋﻠﻰ اﻟﻨﻴﺘﺮوﺟﻴﻦ‬،(‫ﻛﺮﺑﻮن‬. sugar, and a nitrogen-containing base. - The nucleotides in DNA contain the sugar - ‫ﺗﺤﺘﻮي اﻟﻨﻴﻮﻛﻠﻴﻮﺗﻴﺪات اﻟﻤﻮﺟﻮدة ﻓﻲ اﻟﺤﻤﺾ اﻟﻨﻮوي ﻋﻠﻰ ﺳﻜﺮ اﻟﺪﻳﻮﻛﺴﻲ‬ deoxyribose, and the nucleotides in RNA contain the (‫رﻳﺒﻮز)اﻟﺮﻳﺒﻮز ﻣﻨﻘﻮص اﻷوﻛﺴﺠﻴﻦ‬. sugar ribose; this difference accounts for their ‫وﺗﺤﺘﻮي اﻟﻨﻴﻮﻛﻠﻴﻮﺗﻴﺪات اﻟﻤﻮﺟﻮدة ﻓﻲ اﻟﺤﻤﺾ اﻟﻨﻮوي اﻟﺮﻳﺒﻲ ﻋﻠﻰ ﺳﻜﺮ‬ respective names, ‫ اﻟﺮﻳﺒﻮز؛ وﻫﺬا اﻻﺧﺘﻼف ﻳﻔﺴﺮ أﺳﻢ ﻛﻞ ﻣﻨﻬﻤﺎ‬. -also, there are four different types of bases in DNA: :‫أﻳﻀﺎ أرﺑﻌﺔ أﻧﻮاع ﻣﺨﺘﻠﻔﺔ ﻣﻦ اﻟﻘﻮاﻋﺪ ﻓﻲ اﻟﺤﻤﺾ اﻟﻨﻮوي‬ ً ‫ ﻫﻨﺎك‬- Adenine (A), Thymine (T), Guanine (G), and ‫ اﻟﺠﺪول‬C) () ‫ واﻟﺴﻴﺘﻮزﻳﻦ‬،( G ) ‫ واﻟﻐﻮاﻧﻴﻦ‬،) ( T‫ واﻟﺜﺎﻳﻤﻴﻦ‬،(A ) ‫اﻷدﻳﻨﻴﻦ‬ Cytosine (C) (Table 1). ).1 - The base can have two rings (adenine or guanine) - ‫ﻳﻤﻜﻦ أن ﺗﺤﺘﻮي اﻟﻘﺎﻋﺪة ﻋﻠﻰ ﺣﻠﻘﺘﻴﻦ )أدﻳﻨﻴﻦ أو ﺟﻮاﻧﻴﻦ( أو ﺣﻠﻘﺔ‬ or one ring (thymine or cytosine). ‫واﺣﺪة‬ - (‫)ﺛﺎﻳﻤﻴﻦ أو ﺳﺎﻳﺘﻮزﻳﻦ‬. - RNA, the base uracil (U) replaces the base thymine. ) ) U ‫ ﺗﺤﻞ اﻟﻘﺎﻋﺪة اﻟﻴﻮراﺳﻴﻞ‬، RNA ‫ ﻓﻲ اﻟﺤﻤﺾ اﻟﻨﻮوي اﻟﺮﻳﺒﻮزي‬- These structures are called bases because their ‫ وﺗﺴﻤﻰ ﻫﺬه اﻟﻬﻴﺎﻛﻞ ﺑﺎﻟﻘﻮاﻋﺪ ﻷن وﺟﻮدﻫﺎ‬. )T(‫ﻣﺤﻞ اﻟﻘﺎﻋﺪة اﻟﺜﺎﻳﻤﻴﻦ‬ presence raises the pH of a solution..‫ﻳﺮﻓﻊ درﺟﺔ اﻟﺤﻤﻮﺿﺔ ﻓﻲ اﻟﻤﺤﻠﻮل‬ - The nucleotides link to make a polynucleotide - ‫ﺗﺮﺗﺒﻂ اﻟﻨﻴﻮﻛﻠﻴﻮﺗﻴﺪات ﻟﺘﻜﻮﻳﻦ ﺑﻮﻟﻲ ﻧﻴﻮﻛﻠﻴﻮﺗﻴﺪ ﻳﺴﻤﻰ ﺳﻠﺴﻠﺔ‬. called a strand. DNA (deoxyribonucleic (‫ )ﺣﻤﺾ اﻟﺪﻳﻮﻛﺴﻲ رﻳﺒﻮﻧﻮﻛﻠﻴﻴﻚ‬DNA acid) - DNA is double-stranded, with the two strands ‫ ﺣﻴﺚ ﺗﻠﺘﻒ اﻟﺴﻠﺴﻠﺘﺎن‬،‫ ﻫﻮ ﻋﺒﺎرة ﻋﻦ ﺳﻠﺴﻠﺘﻴﻦ‬DNA ‫ اﻟﺤﻤﺾ اﻟﻨﻮوي‬- twisted about each other in the form of a double helix ).3 ‫ﺣﻮل ﺑﻌﻀﻬﻤﺎ اﻟﺒﻌﺾ ﻋﻠﻰ ﺷﻜﻞ ﺣﻠﺰون ﻣﺰدوج )اﻟﺸﻜﻞ‬ -(Figure In DNA3). the two strands are held together by ‫ ﻳﺘﻢ رﺑﻂ اﻟﺴﻠﺴﻠﺘﻴﻦ ﻣﻌً ﺎ ﺑﻮاﺳﻄﺔ رواﺑﻂ‬DNA ‫ ﻓﻲ اﻟﺤﻤﺾ اﻟﻨﻮوي‬- hydrogen bonds between the bases..‫ﻫﻴﺪروﺟﻴﻨﻴﺔ ﺑﻴﻦ اﻟﻘﻮاﻋﺪ‬ Figure 3 : DNA structure  - Thymine (T) always pairs with adenine (A), and )G) ‫ وﻳﻘﺘﺮن اﻟﺠﻮاﻧﻴﻦ‬،( A ) ‫داﺋﻤﺎ ﻣﻊ اﻷدﻳﻨﻴﻦ‬ ً ( T) ‫ ﻳﻘﺘﺮن اﻟﺜﺎﻳﻤﻴﻦ‬- guanine (G) always pairs with cytosine (C). )C). ‫داﺋﻤﺎ ﻣﻊ اﻟﺴﻴﺘﻮزﻳﻦ‬ ً RNA (Ribonucleic (‫ ﺣﻤﺾ اﻟﺮﻳﺒﻮﻧﻮﻛﻠﻴﻴﻚ‬RNA) acid) - RNA is single-stranded. RNA is the nucleic acid ‫ وﻫﻮ ﻳﺸﺎرك ﺑﺸﻜﻞ ﻣﺒﺎﺷﺮ ﻓﻲ‬،‫ ﻫﻮ ﺣﻤﺾ ﻧﻮوي أﺣﺎدي اﻟﺴﻠﺴﻠﺔ‬RNA- directly involved in protein synthesis..‫ﺗﺨﻠﻴﻖ اﻟﺒﺮوﺗﻴﻦ‬ - RNA main types contains: :‫ ﺗﺤﺘﻮي ﻋﻠﻰ‬RNA ‫ اﻷﻧﻮاع اﻟﺮﺋﻴﺴﻴﺔ ﻟﻠـ‬- 1-Messenger RNA (mRNA) is a temporary copy of a ‫ﻫﻲ ﻧﺴﺨﺔ ﻣﺆﻗﺘﺔ ﻣﻦ ﺟﻴﻦ ﻓﻲ اﻟﺤﻤﺾ‬: - Messenger RNA ) mRNA( gene in the DNA that specifies what the amino acid ‫ اﻟﺬي ﻳﺤﺪد ﻣﺎ ﺳﻴﻜﻮن ﻋﻠﻴﻪ ﺗﺴﻠﺴﻞ اﻷﺣﻤﺎض اﻷﻣﻴﻨﻴﺔ أﺛﻨﺎء‬DNA ‫اﻟﻨﻮوي‬ sequence will be during protein synthesis..‫ﺗﺨﻠﻴﻖ اﻟﺒﺮوﺗﻴﻦ‬ 2-Transfer RNA (tRNA) is necessary in synthesizing ‫ﺿﺮوري ﻓﻲ ﺗﺼﻨﻴﻊ اﻟﺒﺮوﺗﻴﻨﺎت وﻳﺴﺎﻋﺪ ﻓﻲ‬: (( tRNA ‫ اﻟﻨﺎﻗﻞ‬- RNA proteins and helps translate the sequence of nucleic.‫ﺗﺮﺟﻤﺔ ﺗﺴﻠﺴﻞ اﻷﺣﻤﺎض اﻟﻨﻮوﻳﺔ ﻓﻲ اﻟﺠﻴﻦ أﺛﻨﺎء ﺗﺼﻨﻴﻊ اﻟﺒﺮوﺗﻴﻦ‬ acids in a during protein synthesis. 3-Ribosomal RNA (rRNA) is the RNA component of ‫ وﻳﻌﻤﻞ‬،‫ ﻟﻠﺮﻳﺒﻮﺳﻮم‬RNA ‫ ﻫﻮ ﻣﻜﻮن‬:( ( rRNA ‫ اﻟﺮﻳﺒﻮﺳﻮﻣﻲ‬- RNA the ribosome, it works as an enzyme to form the.‫ﻛﺄﻧﺰﻳﻢ ﻟﺘﺸﻜﻴﻞ اﻟﺮواﺑﻂ اﻟﺒﺒﺘﻴﺪﻳﺔ ﺑﻴﻦ اﻷﺣﻤﺎض اﻷﻣﻴﻨﻴﺔ ﻓﻲ اﻟﺒﻮﻟﻴﺒﺒﺘﻴﺪ‬ peptide bonds between amino acids in a polypeptide. Differences in the Structures of DNA ‫ واﻟﺤﻤﺾ اﻟﻨﻮوي اﻟﺮﻳﺒﻮزي‬DNA ‫اﻻﺧﺘﻼﻓﺎت ﻓﻲ ﺑﻨﻴﺔ اﻟﺤﻤﺾ اﻟﻨﻮوي‬ and RNA RNA RNA DNA Comparison :Point Ribose Deoxyribose Ribose Sugar Adenine, guanine, uracil, Adenine, guanine, thymine, Bases cytosine cytosine Single-stranded Double-stranded with base Strands pairing No YesDNA and RNA Table 1: Comparison between Helix Structure