Biophysics Midterm Answer PDF

1.What is the head of a phospholipid made of? The head of a phospholipid is made of a glycerol molecule attached to a phosphate group, which is often linked to another molecule like choline or ethanolamine. The head is hydrophilic (water-attracting) ‫ وغالبًا ما تكون المجموعة الفوسفاتٌة مرتبطة بجز...

1.What is the head of a phospholipid made of? The head of a phospholipid is made of a glycerol molecule attached to a phosphate group, which is often linked to another molecule like choline or ethanolamine. The head is hydrophilic (water-attracting) ‫ وغالبًا ما تكون المجموعة الفوسفاتٌة مرتبطة بجزء آخر‬،‫رأس الفوسفولٌبٌد مكون من جزيء جلسٌرول مرتبط بمجموعة فوسفات‬.)ً‫ الرأس ٌكون محبًا للماء (مائ‬.‫مثل الكولٌن أو اإلٌثانوالمٌن‬ 2. What are cell membranes constructed mainly of? The cell membrane is mainly made of phospholipids. The bilayer (phospholipid bilayer) consists of water-attracting heads (which face outward toward the surrounding fluid) and water-repelling tails (which face inward, away from water( ‫ تتكون الطبقة الثنائٌة (الطبقة الثنائٌة للفوسفولٌبٌد) من رؤوس محبة للماء (التً تتوجه‬.‫غشاء الخلٌة مكون أسا ًسا من الفوسفولٌبٌدات‬.)‫ بعٌ ًدا عن الماء‬،‫نحو الخارج نحو السائل المحٌط) وذٌول كارهة للماء (التً تتوجه نحو الداخل‬ 3.What is the function of the carbohydrates in the cell membrane? The function of carbohydrates in the cell membrane is cell recognition and communication. Carbohydrates are often attached to proteins or lipids in the membrane (forming glycoproteins or glycolipids), and they help with: 1. Cell recognition: For example, identifying self-cells versus foreign cells. 2. Cell communication: Facilitating communication between cells. 3. Protection: Acting as a barrier against microbes and harmful substances ٟ‫ْ ف‬ٛ٘‫ اٌذ‬ٚ‫ٕبد أ‬١‫ر‬ٚ‫ْ غبٌجًب ِشرجطخ ثبٌجش‬ٛ‫ذساد رى‬١٘ٛ‫ اٌىشث‬.‫ انخعشف واالحظبل انخهىي‬ٟ٘ ‫خ‬١ٍ‫ غشبء اٌخ‬ٟ‫ذساد ف‬١٘ٛ‫فخ اٌىشث‬١‫ظ‬ٚ :ٟ‫رغبػذ ف‬ٚ... )‫ انجهٍكىنٍبٍذاث‬ٚ‫ٔخ انجهٍكىبشوحٍُبث أ‬ٛ‫اٌغشبء (ِى‬ ً : ‫ انخعشف عهى انخالٌب‬.1.‫جخ‬٠‫ب اٌغش‬٠‫خ ػٓ اٌخًل‬١‫ب اٌزار‬٠‫ذ اٌخًل‬٠‫ رؾذ‬،‫ِضًل‬.‫ب‬٠‫ٓ اٌخًل‬١‫اطً ث‬ٛ‫ اٌز‬ٟ‫ُ ف‬ٙ‫رغ‬: ‫ االحظبل انخهىي‬.2 ‫اد اٌؼبسح‬ٌّٛ‫ا‬ٚ ‫ثبد‬ٚ‫ىش‬١ٌّ‫ق ػذ ا‬ ٍ ‫ا‬ٚ ‫رؼًّ وؾبعض‬: ‫ انحًبٌت‬.3  4.What is the function of proteins in cell membranes? Proteins in cell membranes play important roles, such as: 1. Transport: They facilitate the movement of substances in and out of the cell. 2. Signaling: They receive external signals and transmit them inside the cell. 3. Support: They help maintain the cell’s shape. 4. Recognition: They aid cells in recognizing each other. 5. Catalysis: They act as enzymes to speed up chemical reactions. These functions make membrane proteins essential for cell function. :‫ مثل‬،‫تلعب البروتٌنات فً أغشٌة الخالٌا أدوارً ا مهمة‬.‫تسهل مرور المواد داخل وخارج الخلٌة‬: ‫ النقل‬.1.‫تستقبل إشارات خارجٌة وتنقلها إلى داخل الخلٌة‬: ‫ اإلشارات‬.2.‫تحافظ على شكل الخلٌة‬: ‫ الدعم‬.3.‫تساعد الخالٌا على التعرف على بعضها‬: ‫ التعرف‬.4.‫تعمل كإنزٌمات لتسرٌع التفاعالت الكٌمٌائٌة‬: ‫ التحفيز‬.5.‫هذه الوظائف تجعل بروتٌنات الغشاء أساسٌة لعمل الخلٌة‬ 5.What are isotonic, hypertonic and hypotonic solutions? These are types of solutions that affect water movement in and out of cells: 1. Isotonic Solution: The concentration of solutes outside the cell is equal to that inside the cell, so there is no change in cell size because water movement is balanced. 2. Hypertonic Solution: The concentration of solutes outside the cell is higher than inside, causing water to leave the cell, making it shrink. 3. Hypotonic Solution: The concentration of solutes outside the cell is lower than inside, causing water to enter the cell, which may make it swell. These types determine the direction of water movement and affect cell size :‫ب‬٠‫خبسط اٌخًل‬ٚ ً‫ ؽشوخ اٌّبء داخ‬ٍٝ‫ رؤصش ػ‬ٟ‫ً اٌز‬١ٌ‫اع اٌّؾب‬ٛٔ‫ أ‬ٟ٘ ٖ‫٘ز‬ ٟ‫ش ف‬١١‫ؾذس رغ‬٠ ‫ فًل‬،‫خ‬١ٍ‫ض٘ب داخً اٌخ‬١‫ رشو‬ٞٚ‫غب‬٠ ‫خ‬١ٍ‫اد اٌّزاثخ خبسط اٌخ‬ٌّٛ‫ض ا‬١‫ رشو‬: - ‫ يحهىل يخسبوي انخىحش‬- Isotonic.1.‫اصٔخ‬ٛ‫خ ألْ ؽشوخ اٌّبء ِز‬١ٍ‫ؽغُ اٌخ‬ ٌٝ‫ إ‬ٞ‫ؤد‬٠ ‫ ِّب‬،‫خ‬١ٍ‫ض٘ب داخً اٌخ‬١‫ ِٓ رشو‬ٍٝ‫خ أػ‬١ٍ‫اد اٌّزاثخ خبسط اٌخ‬ٌّٛ‫ض ا‬١‫رشو‬: - ‫ يحهىل عبنً انخىحش‬- Hypertonic.2.‫ فززمٍض‬،‫خ‬١ٍ‫ط اٌّبء ِٓ اٌخ‬ٚ‫خش‬ ٌٝ‫ذخً اٌّبء إ‬١‫ ف‬،‫خ‬١ٍ‫ض٘ب داخً اٌخ‬١‫خ ألً ِٓ رشو‬١ٍ‫اد اٌّزاثخ خبسط اٌخ‬ٌّٛ‫ض ا‬١‫ سو‬: - ‫ يحهىل يُخفض انخىحش‬- Hypotonic.3.‫ب‬ٙ‫ أزفبخ‬ٌٝ‫ إ‬ٞ‫ؤد‬٠ ‫ ِّب لذ‬،‫خ‬١ٍ‫اٌخ‬ ‫ب‬٠‫ ؽغُ اٌخًل‬ٍٝ‫رؤصش ػ‬ٚ ‫اع رؾذد ارغبٖ ؽشوخ اٌّبء‬ٛٔ‫٘زٖ األ‬  6. Differentiate between osmosis and diffusion. Osmosis and Diffusion are both transport processes, but there are differences: 1. Osmosis: The movement of water only, from an area of low solute concentration to an area of high solute concentration through a semi-permeable membrane. 2. Diffusion: The movement of molecules (such as gas or solutes) from an area of high concentration to an area of low concentration, and it can happen in air, liquids, or across a membrane. Main Difference: Osmosis is only for water movement, while diffusion involves the movement of any molecules. :‫ّب اخزًلفبد‬ٕٙ١‫ ٌىٓ ث‬،‫بد أزمبي‬١ٍّ‫ ّ٘ب ػ‬Diffusion ٚ Osmosis ‫اد اٌّزاثخ ػجش‬ٌّٛ‫ض ػب ٍي ِٓ ا‬١‫ ِٕطمخ رشو‬ٌٝ‫اد اٌّزاثخ إ‬ٌٍّٛ ‫ض ِٕخفغ‬١‫ أزمبي اٌّبء فمؾ ِٓ ِٕطمخ رشو‬: ‫ انخُبضح‬Osmosis.1.‫غشبء شجٗ ٔبفز‬ ‫ض‬١‫ ِٕطمخ راد رشو‬ٌٝ‫ض ػب ٍي إ‬١‫اد اٌّزاثخ) ِٓ ِٕطمخ راد رشو‬ٌّٛ‫ ا‬ٚ‫ئبد (ِضً اٌغبص أ‬٠‫ أزمبي اٌغض‬: ‫ االَخشبس‬- Diffusion.2.‫ ػجش غشبء‬ٚ‫ أ‬،ً‫ائ‬ٛ‫ اٌغ‬ٚ‫ أ‬،‫اء‬ٌٛٙ‫ ا‬ٟ‫ؾذس ف‬٠ ‫لذ‬ٚ ،‫ِٕخفغ‬ ‫ئب‬٠‫ عض‬ٞ‫شًّ ؽشوخ أ‬٠ ‫ّٕب االٔزشبس‬١‫ ث‬،‫خ رخض ؽشوخ اٌّبء فمؾ‬٠‫ص‬ّٛ‫األع‬: ً‫انفشق األسبس‬ 7. What is reverse osmosis? Reverse osmosis is a process used to separate water from dissolved substances. In this process: 1. Water is pushed through a semi-permeable membrane, but in the opposite direction of natural osmosis. 2. High pressure is applied to force the water from an area of high solute concentration to an area of low solute concentration. 3. This allows impurities and contaminants to be removed, resulting in pure water. This technique is used in water purification, wastewater treatment, and producing fresh water from seawater :‫خ‬١ٍّ‫ ٘زٖ اٌؼ‬ٟ‫ ف‬.ٗ١‫اد اٌّزاثخ ف‬ٌّٛ‫خ رغزخذَ ٌفظً اٌّبء ػٓ ا‬١ٍّ‫ ػ‬ٛ٘ "‫"األسموزٌة العكسٌة‬ reverse osmosis.ٟ‫ؼ‬١‫ ٌىٓ ثؼىظ ارغبٖ اٌزٕبػؼ اٌطج‬،‫زُ دفغ اٌّبء ػجش غشبء شجٗ ٔبفز‬٠.1.‫ض ِٕخفغ‬١‫ ِٕطمخ راد رشو‬ٌٝ‫اد اٌّزاثخ إ‬ٌّٛ‫ض ػب ٍي ِٓ ا‬١‫ُغزخذَ ػغؾ ػب ٍي ٌطشد اٌّبء ِٓ ِٕطمخ راد رشو‬٠.2.ٟ‫ٕزظ ػٕٗ ِبء ٔم‬٠ ‫ ِّب‬،‫صبد‬ٌٍّٛ‫ا‬ٚ ‫ائت‬ٛ‫غّؼ ثئصاٌخ اٌش‬٠ ‫ ٘زا‬.3 ‫بٖ اٌجؼ‬١ِ ِٓ ‫بٖ اٌؼزثخ‬١ٌّ‫إٔزبط ا‬ٚ ،‫بٖ اٌظشف‬١ِ ‫ِؼبٌغخ‬ٚ ،ٖ‫ب‬١ٌّ‫خ ا‬١ٍ‫رؾ‬ٚ ‫خ‬١‫ رٕم‬ٟ‫خ ف‬١ٕ‫رُغزخذَ ٘زٖ اٌزم‬  8. Give some examples of osmosis that we encounter in everyday life? some examples of osmosis we encounter in everyday life: 1. Absorption of Water by Plants: Roots of plants absorb water from the soil through osmosis, moving water from an area of low concentration in the soil to high concentration in the plant cells. 2. Salting Vegetables: When salt is applied to vegetables, water moves out of the cells of the vegetable by osmosis, causing them to shrink. 3. Kidney Function: In our kidneys, osmosis helps regulate the balance of water and salts in the body by filtering blood and reabsorbing water. These are common examples of osmosis in nature and daily activities :‫خ‬١ِٛ١ٌ‫برٕب ا‬١‫ ؽ‬ٟ‫ب ف‬ٙٙ‫اع‬ٛٔ ٟ‫ اٌزٕبػؼ اٌز‬ٍٝ‫ثؼغ األِضٍخ ػ‬ ‫زؾشن اٌّبء ِٓ ِٕطمخ راد‬٠ ‫ش‬١‫ ؽ‬،‫س إٌجبربد اٌّبء ِٓ اٌزشثخ ػجش اٌزٕبػؼ‬ٚ‫رّزض عز‬: ‫ ايخظبص انًبء بىاسطت انُببحبث‬.1.‫ب إٌجبد‬٠‫ خًل‬ٟ‫ض ػب ٍي ف‬١‫ رشو‬ٌٝ‫ اٌزشثخ إ‬ٟ‫ض ِٕخفغ ف‬١‫رشو‬ ٞ‫ؤد‬٠ ‫ ِّب‬،‫ب اٌخؼبس ػجش اٌزٕبػؼ‬٠‫زؾشن اٌّبء خبسط خًل‬٠ ،‫اد‬ٚ‫ اٌخؼش‬ٌٝ‫ُؼبف اٌٍّؼ إ‬٠ ‫ػٕذِب‬: ‫ سش انًهح عهى انخضشواث‬.2.‫ب‬ٙ‫ أىّبش‬ٌٝ‫إ‬ ‫إػبدح اِزظبص‬ٚ َ‫خ اٌذ‬١‫ك رظف‬٠‫ اٌغغُ ػٓ ؽش‬ٟ‫األًِلػ ف‬ٚ ‫اصْ اٌّبء‬ٛ‫ُ ر‬١‫ رٕظ‬ٟ‫غبػذ اٌزٕبػؼ ف‬٠ ،ٍٝ‫ اٌى‬ٟ‫ ف‬: ‫ وظٍفت انكهى‬.3.‫اٌّبء‬ ‫خ‬١ِٛ١ٌ‫األٔشطخ ا‬ٚ ‫ؼخ‬١‫ اٌطج‬ٟ‫٘زٖ ثؼغ األِضٍخ اٌشبئؼخ ٌٍزٕبػؼ ف‬ 9. What is dialysis? Dialysis is a medical process used to remove waste, excess water, and toxins from the blood when the kidneys are not functioning properly. There are two main types: 1. Hemodialysis: Blood is passed through a machine that filters out waste and excess fluids, and then the clean blood is returned to the body. 2. Peritoneal Dialysis: The inside of the abdomen is used as a filter. A special solution is introduced into the abdominal cavity to absorb waste and excess fluids, which are then drained out. Dialysis helps maintain the body's balance of water, salts, and waste when the kidneys can no longer do so effectively.‫ؼ‬١‫ ثشىً طؾ‬ٍٝ‫َ ِٓ اٌذَ ػٕذِب ال رؼًّ اٌى‬ّٛ‫اٌغ‬ٚ ‫اٌّبء اٌضائذ‬ٚ ‫خ رُغزخذَ إلصاٌخ اٌفؼًلد‬١‫خ ؽج‬١ٍّ‫ ػ‬ٛ٘ ‫انغسٍم انكهىي‬ :ْ‫ب‬١‫غ‬١‫ػبْ سئ‬ٛٔ ‫ٕ٘بن‬.ُ‫ اٌغغ‬ٌٝ‫ف إ‬١‫ُؼبد اٌذَ إٌظ‬٠ ُ‫ ص‬،‫ائً اٌضائذح‬ٛ‫اٌغ‬ٚ ‫ٗ ِٓ اٌفؼًلد‬١‫ٕم‬٠ ‫بص‬ٙ‫ُّشس اٌذَ ػجش ع‬٠: ‫ انغسٍم انكهىي انذيىي‬.1  ‫ف اٌجطٓ الِزظبص اٌفؼًلد‬٠ٛ‫ رغ‬ٌٝ‫ي خبص إ‬ٍٛ‫ُؼبف ِؾ‬٠.‫زُ اعزخذاَ داخً اٌجطٓ وّششؼ‬٠: ًَ‫ انغسٍم انكهىي انبشٌخى‬.2.ٗ‫ف‬٠‫زُ رظش‬٠ ُ‫ ص‬،‫ائً اٌضائذح‬ٛ‫اٌغ‬ٚ ‫بَ ثزٌه ثشىً فؼبي‬١‫ ِٓ اٌم‬ٍٝ‫اٌفؼًلد ػٕذِب ال رزّىٓ اٌى‬ٚ ‫األًِلػ‬ٚ ‫اصْ اٌغغُ ِٓ اٌّبء‬ٛ‫ ر‬ٍٝ‫ اٌؾفبظ ػ‬ٟ‫ ف‬ٍٞٛ‫ً اٌى‬١‫غبػذ اٌغغ‬٠ 10. Explain different types of diffusion. Diffusion is the process by which molecules or particles spread from an area of higher concentration to an area of lower concentration. the types of diffusion: 1. Simple Diffusion: The movement of molecules from an area of high concentration to low concentration across a semi-permeable membrane without the need for energy. 2. Facilitated Diffusion: The movement of molecules across a membrane using transport proteins, without the need for energy. 3. Osmosis: The movement of water across a semi-permeable membrane from an area of low solute concentration to high solute concentration. 4. Active Diffusion: The movement of molecules against their concentration gradient using energy (ATP)..‫عال إلى منطقة ذات تركٌز منخفض‬ ٍ ‫االنتشار هو العملٌة التً تنتشر فٌها الجزٌئات أو الجسٌمات من منطقة ذات تركٌز‬ :‫اع االٔزشبس‬ٛٔ ٌٝ‫ْ اٌؾبعخ إ‬ٚ‫ د‬ٞ‫ض ػجش غشبء شجٗ ٔفبر‬١‫ ِٕطمخ ِٕخفؼخ اٌزشو‬ٌٝ‫ض إ‬١‫خ اٌزشو‬١ٌ‫ئبد ِٓ ِٕطمخ ػب‬٠‫ ؽشوخ اٌغض‬: ‫االَخشبس انبسٍظ‬.1.‫ؽبلخ‬.‫ْ ؽبعخ ٌٍطبلخ‬ٚ‫ د‬،ً‫ٕبد ٔم‬١‫ر‬ٚ‫خ ثبعزخذاَ ثش‬١ٍ‫ئبد ػجش غشبء خ‬٠‫ؽشوخ اٌغض‬: ‫االَخشبس انًٍسش‬.2.‫ض‬١‫خ اٌزشو‬١ٌ‫ ػب‬ٌٝ‫ض إ‬١‫ ِٓ ِٕطمخ ِٕخفؼخ اٌزشو‬ٞ‫ؽشوخ اٌّبء ػجش غشبء شجٗ ٔفبر‬: ‫االَخشبس األسًىصي‬.3 (ATP).‫ض ثبعزخذاَ اٌطبلخ‬١‫ئبد ػذ اٌزذسط اٌزشو‬٠‫ؽشوخ اٌغض‬: ‫االَخشبس انُشظ‬.4 11.What is the function of the cell membrane? The cell membrane performs several key functions: 1. Selective Permeability: Allows beneficial substances to enter and waste to exit. 2. Protection and Support: Protects the cell and maintains its shape. 3. Communication: Contains receptors to receive signals from the external environment. 4. Cell Recognition: Helps in recognizing other cells. 5. Anchoring the Cytoskeleton: Contributes to maintaining the cell's shape and movement. 6. Transport: Regulates the transport of substances across the membrane using channel or pump proteins  :‫خ‬١‫ظبئف أعبع‬ٚ ‫َ ثؼذح‬ٛ‫م‬٠ ‫خ‬١ٍ‫غشبء اٌخ‬.‫بد‬٠‫ط إٌفب‬ٚ‫خش‬ٚ ‫ذح‬١‫اد اٌّف‬ٌّٛ‫ي ا‬ٛ‫غّؼ ثذخ‬٠: ‫انُفبرٌت االَخقبئٍت‬.1.‫ب‬ٍٙ‫ شى‬ٍٝ‫ؾبفع ػ‬٠ٚ ‫خ‬١ٍ‫ اٌخ‬ّٟ‫ؾ‬٠: ‫انحًبٌت وانذعى‬.2.‫خ‬١‫ئخ اٌخبسع‬١‫ ِغزمجًلد العزمجبي اإلشبساد ِٓ اٌج‬ٍٝ‫ ػ‬ٞٛ‫ؾز‬٠: ‫انخىاطم‬.3.ٜ‫ب األخش‬٠‫ اٌخًل‬ٍٝ‫ اٌزؼشف ػ‬ٟ‫غبػذ ف‬٠: ‫انخعشف انخهىي‬.4.‫ب‬ٙ‫ؽشوز‬ٚ ‫خ‬١ٍ‫ شىً اٌخ‬ٍٝ‫ اٌؾفبظ ػ‬ٟ‫غبُ٘ ف‬٠: ‫سبظ انهٍكم انخهىي‬.5.‫ اٌّؼخبد‬ٚ‫ٕبد اٌمٕبح أ‬١‫ر‬ٚ‫اد ػجش اٌغشبء ثبعزخذاَ ثش‬ٌّٛ‫ٕظُ ٔمً ا‬٠: ‫انُقم‬.6 12.What are the 7 functions of the cell membrane? functions of the cell membrane: 1. Selective Permeability: Regulates the entry and exit of materials. 2. Protection: Protects the cell's contents from harmful substances. 3. Support: Maintains the cell's shape. 4. Communication: Receives signals from the external environment. 5. Cell Recognition: Helps recognize other cells. 6. Anchoring the Cytoskeleton: Connects the membrane to the cell's internal structure. 7. Transport: Facilitates the movement of materials across the membrane using transport proteins :‫خ‬١ٍ‫ظبئف غشبء اٌخ‬ٚ.‫اد‬ٌّٛ‫ط ا‬ٚ‫خش‬ٚ ‫ي‬ٛ‫ٕظُ دخ‬٠: ‫انُفبرٌت االَخقبئٍت‬.1.‫اد اٌؼبسح‬ٌّٛ‫خ ِٓ ا‬١ٍ‫بد اٌخ‬٠ٛ‫ ِؾز‬ّٟ‫ؾ‬٠: ‫انحًبٌت‬.2.‫خ‬١ٍ‫ شىً اٌخ‬ٍٝ‫ؾبفع ػ‬٠: ‫انذعى‬.3.‫خ‬١‫ئخ اٌخبسع‬١‫غزمجً إشبساد ِٓ اٌج‬٠: ‫انخىاطم‬.4.ٜ‫ب األخش‬٠‫ اٌخًل‬ٍٝ‫ اٌزؼشف ػ‬ٟ‫غبػذ ف‬٠: ‫انخعشف انخهىي‬.5.‫خ‬١ٍ‫ ٌٍخ‬ٍٟ‫ىً اٌذاخ‬١ٌٙ‫شثؾ اٌغشبء ثب‬٠: ‫سبظ انهٍكم انخهىي‬.6.ً‫ٕبد إٌم‬١‫ر‬ٚ‫اد ػجش اٌغشبء ثبعزخذاَ ثش‬ٌّٛ‫ً ٔمً ا‬ٙ‫غ‬٠: ‫انُقم‬.7 13.What is a cell membrane made of? The cell membrane is made up of: 1. Phospholipids: Form the bilayer structure, which is the basic framework of the membrane. 2. Proteins: Located on the surface or across the membrane, aiding in transport and communication. 3. Carbohydrates: Attached to proteins or lipids, helping with cell recognition. 4. Cholesterol: Enhances the membrane's flexibility and stability. Function: The membrane controls the entry and exit of materials and participates in cell communication :ٍ‫انغشبء انخهىي ٌخكىٌ ي‬.‫ىً اٌغشبء‬١٘ ‫ رؼزجش‬ٟ‫خ اٌز‬١‫رشىً اٌطجمخ اٌضٕبئ‬: ‫ انفىسفىنٍبٍذاث‬.1.ً‫اط‬ٛ‫اٌز‬ٚ ً‫ إٌم‬ٟ‫رغبػذ ف‬ٚ ،ٖ‫ ػجش‬ٚ‫ عطؼ اٌغشبء أ‬ٍٝ‫عذ ػ‬ٛ‫ر‬: ‫ انبشوحٍُبث‬.2.‫ب‬٠‫ اٌخًل‬ٍٝ‫ اٌزؼشف ػ‬ٟ‫رغبػذ ف‬ٚ ،ْٛ٘‫ اٌذ‬ٚ‫ٕبد أ‬١‫ر‬ٚ‫ِشرجطخ ثبٌجش‬: ‫ انكشبىهٍذساث‬.3.ٖ‫اعزمشاس‬ٚ ‫ٔخ اٌغشبء‬ٚ‫ؾغٓ ِش‬٠: ‫ انكىنٍسخشول‬.4.‫ب‬٠‫ٓ اٌخًل‬١‫اطً ث‬ٛ‫ اٌز‬ٟ‫شبسن ف‬٠ٚ ‫اد‬ٌّٛ‫ط ا‬ٚ‫خش‬ٚ ‫ي‬ٛ‫ دخ‬ٟ‫زؾىُ اٌغشبء ف‬٠: ‫انىظٍفت‬ 14.What are the three proteins in the cell membrane? Three types of proteins in the cell membrane: 1. Peripheral Proteins: Located on the surface of the membrane, aiding in structural support and cell communication. 2. Integral Proteins: Span across the membrane, functioning as channels or transporters. 3. Glycoproteins: Attached to carbohydrates, helping with cell recognition :‫ثالثت أَىاع يٍ انبشوحٍُبث فً انغشبء انخهىي‬.ٍٞٛ‫اطً اٌخ‬ٛ‫اٌز‬ٚ ً‫ى‬١ٌٙ‫ دػُ ا‬ٟ‫رغبػذ ف‬ٚ ‫ عطؼ اٌغشبء‬ٍٝ‫رمغ ػ‬: ‫ انبشوحٍُبث انًحٍطٍت‬.1.‫ ٔبلًلد‬ٚ‫اد أ‬ٕٛ‫رؼًّ وم‬ٚ ‫رّزذ ػجش اٌغشبء‬: ‫ انبشوحٍُبث انًذيجت‬.2.‫ب‬٠‫ اٌخًل‬ٍٝ‫ اٌزؼشف ػ‬ٟ‫رغبػذ ف‬ٚ ‫ذساد‬١٘ٛ‫ِشرجطخ ثبٌىشث‬: ‫ انبشوحٍُبث انسطحٍت‬.3 15.Are cell membranes fluid and flexible? Explain Yes, cell membranes are fluid and flexible. Explanation:  Fluid Structure: Due to the arrangement of phospholipid bilayers, where phospholipids and molecules move continuously, making the membrane flexible and adaptable.  Flexibility: The cell membrane can stretch and shrink easily, thanks to the presence of cholesterol, which helps maintain stability and flexibility at different temperatures..ٌ‫ انغشبء انخهىي سبئم ويش‬،‫َعى‬ :‫انخفسٍش‬ ً‫ئبد ػجش اٌغشبء ثشى‬٠‫اٌغض‬ٚ ‫ذاد‬١‫ج‬١ٌٛ‫عف‬ٛ‫ش رزؾشن اٌف‬١‫ ؽ‬،‫ت انطبقت انثُبئٍت نهفىسفىنٍبٍذاث‬١‫ثغجت رشو‬: ‫انهٍكم انسبئم‬ .‫شاد‬١‫ف ِغ اٌزغ‬١‫ اٌزى‬ٍٝ‫لبد ًسا ػ‬ٚ ‫غؼً اٌغشبء ِشًٔب‬٠ ‫ ِّب‬،‫ِغزّش‬ ٖ‫ اعزمشاس‬ٍٝ‫ اٌؾفبظ ػ‬ٟ‫غبػذ ف‬٠ ٞ‫د انكىنٍسخشول اٌز‬ٛ‫ع‬ٚ ً‫ٌخ ثفؼ‬ٛٙ‫االٔىّبػ ثغ‬ٚ ‫ّىٕٗ اٌزّذد‬٠ ٍٞٛ‫اٌغشبء اٌخ‬: ‫انًشوَت‬ .‫ دسعبد ؽشاسح ِخزٍفخ‬ٟ‫ٔزٗ ف‬ٚ‫ِش‬ٚ  16.What are the 4 main functions of proteins on the cell membrane? Four main functions of proteins on the cell membrane: 1. Transport: Proteins act as channels or transporters to move substances across the membrane. 2. Reception: Surface proteins serve as receptors for chemical signals, such as hormones. 3. Structural Support: Proteins provide structural support and anchor the membrane to the cell's internal framework. 4. Cell Recognition: Glycoproteins help in cell recognition and interactions with other cells :‫اسبع وظبئف سئٍسٍت نهبشوحٍُبث عهى انغشبء انخهىي‬.‫اد ػجش اٌغشبء‬ٌّٛ‫ ٔبلًلد ٌٕمً ا‬ٚ‫اد أ‬ٕٛ‫ٕبد رؼًّ وم‬١‫ر‬ٚ‫( اٌجش‬Transport): ‫انُقم‬.1.‫ٔبد‬ِٛ‫ش‬ٌٙ‫خ ِضً ا‬١‫بئ‬١ّ١‫خ رؼًّ وّغزمجًلد ٌٍشعبئً اٌى‬١‫ٕبد اٌغطؾ‬١‫ر‬ٚ‫( اٌجش‬Reception): ‫االسخقببل‬.2.‫خ‬١ٍ‫ ٌٍخ‬ٍٟ‫ىً اٌذاخ‬١ٌٙ‫رشثطٗ ِغ ا‬ٚ ٍٞٛ‫ٕبد رذػُ اٌغشبء اٌخ‬١‫ر‬ٚ‫( اٌجش‬Structural Support): ً‫انذعى انهٍكه‬.3 ‫ب‬ٍٙ‫رفبػ‬ٚ ‫ب‬٠‫ اٌخًل‬ٍٝ‫ اٌزؼشف ػ‬ٟ‫ذساد رغبػذ ف‬١٘ٛ‫ٕبد اٌّشرجطخ ثبٌىشث‬١‫ر‬ٚ‫( اٌجش‬Cell Recognition): ‫انخعشف عهى انخالٌب‬.4.‫ب‬ٙ‫ِغ ثؼؼ‬ 17.What are 6 common functions of membrane proteins? Six common functions of membrane proteins: 1. Transport: Transport substances across the membrane using channels or transporters. 2. Receptor: Receive chemical signals, such as hormones. 3. Structural Support: Anchor the membrane to the cell's internal structure. 4. Cell Recognition: Recognize other cells through glycoproteins. 5. Enzyme Activity: Catalyze chemical reactions on the membrane surface. 6. Intercellular Joining: Link cells together to maintain tissue cohesion :‫سج وظبئف شبئعت نهبشوحٍُبث انغشبئٍت‬.‫ إٌبلًلد‬ٚ‫اد أ‬ٕٛ‫اد ػجش اٌغشبء ثبعزخذاَ اٌم‬ٌّٛ‫( ٔمً ا‬Transport): ‫انُقم‬.1.‫ٔبد‬ِٛ‫ش‬ٌٙ‫خ ِضً ا‬١‫بئ‬١ّ١‫( اعزمجبي اإلشبساد اٌى‬Receptor): ‫االسخقببل‬.2.‫خ‬١ٍ‫ ٌٍخ‬ٍٟ‫ىً اٌذاخ‬١ٌٙ‫( سثؾ اٌغشبء ثب‬Structural Support): ً‫انذعى انهٍكه‬.3.‫ٕبد‬١‫ر‬ٚ‫ثش‬ٛ‫ى‬١ٍ‫ ِٓ خًلي اٌغ‬ٜ‫ب األخش‬٠‫ اٌخًل‬ٍٝ‫( اٌزؼشف ػ‬Cell Recognition): ‫انخعشف عهى انخالٌب‬.4.‫ عطؼ اٌغشبء‬ٍٝ‫خ ػ‬١‫بئ‬١ّ١‫ض اٌزفبػًلد اٌى‬١‫( رؾف‬Enzyme Activity): ‫انشبظ ببألَضًٌبث‬.5.‫ رّبعه األٔغغخ‬ٍٝ‫ب اٌجؼغ ٌٍؾفبظ ػ‬ٙ‫ب ثجؼؼ‬٠‫( سثؾ اٌخًل‬Intercellular Joining): ‫انخًبسك بٍٍ انخالٌب‬.6  18.What is the main purpose of the cell membrane? The main purpose of the cell membrane is: To regulate the movement of substances into and out of the cell, helping to maintain the cell's internal balance (homeostasis) and protect it from harmful substances. It also plays a role in cell communication and recognition. :‫انهذف انشئٍسً نهغشبء انخهىي هى‬ homeostasis) ٚ‫ أ‬ٍٟ‫اصْ اٌذاخ‬ٛ‫خ (اٌز‬١ٍ‫ ٌٍخ‬ٍٟ‫اصْ اٌذاخ‬ٛ‫ اٌز‬ٍٝ‫ اٌؾفبظ ػ‬ٟ‫غبػذ ف‬٠ ‫ ِّب‬،‫خ‬١ٍ‫خبسط اٌخ‬ٚ ً‫اد داخ‬ٌّٛ‫س ا‬ٚ‫ُ ِش‬١‫رٕظ‬.‫ب‬ٙ١ٍ‫اٌزؼشف ػ‬ٚ ‫ب‬٠‫ٓ اٌخًل‬١‫اطً ث‬ٛ‫ اٌز‬ٟ‫شبسن ف‬٠ ‫ وّب‬.‫اد اٌؼبسح‬ٌّٛ‫ا‬ٚ ‫صبد‬ٌٍّٛ‫ب ِٓ ا‬ٙ‫ز‬٠‫ؽّب‬ٚ 19.Are membranes soluble in water? Explain Membranes are insoluble in water. Explanation: The cell membrane is primarily made of phospholipids, which have a water-loving (hydrophilic) head and a water-fearing (hydrophobic) tail. The hydrophilic heads face outward (toward the water), while the hydrophobic tails face inward, making the membrane insoluble in water. This structure allows the membrane to act as a barrier, protecting the cell from losing water and maintaining its integrity.‫انغشبء غٍش قببم نهزوببٌ فً انًبء‬.)ً٠‫عضء وبسٖ ٌٍّبء (ر‬ٚ )‫ عضء ِؾت ٌٍّبء (سأط‬ٍٝ‫ ػ‬ٞٛ‫ رؾز‬ٟ‫ ِٓ انفىسفىنٍبٍذاث اٌز‬ٟ‫غ‬١‫ْ ثشىً سئ‬ٛ‫زى‬٠ ٍٞٛ‫اٌغشبء اٌخ‬: ‫انخفسٍش‬ ْ‫ثب‬ٚ‫ش لبثً ٌٍز‬١‫غؼً اٌغشبء غ‬٠ ‫ ِّب‬،ً‫ اٌذاخ‬ٛ‫بي اٌىبس٘خ ٌٍّبء رزغٗ ٔؾ‬٠‫ّٕب األر‬١‫ ث‬،)‫ اٌّبء‬ٛ‫ اٌخبسط (ٔؾ‬ٛ‫ط اٌّؾجخ ٌٍّبء رزغٗ ٔؾ‬ٚ‫اٌشؤ‬.‫خ‬١‫اد اٌّبئ‬ٌّٛ‫ب ِٓ فمذاْ ا‬ٙ١ّ‫ؾ‬٠ٚ ‫خ‬١ٍ‫ اٌخ‬ٍٝ‫ؾبفع ػ‬٠ ‫خ رغؼً اٌغشبء ؽبع ًضا‬١ٕ‫ ٘زٖ اٌج‬.‫ اٌّبء‬ٟ‫ف‬ 20.What will happen if the cell has no cell membrane? If the cell has no cell membrane, the following will happen: 1. Loss of Protection: The cell will lose its protection from harmful substances. 2. Imbalance: It will be unable to regulate the entry and exit of materials. 3. Cell Destruction: The cell's contents will be damaged and leak out. 4. Failure in Communication: The cell will lose the ability to receive signals from the outside. 5. Halting Vital Functions: The cell will be unable to perform its essential functions  :ٍٟ٠ ‫ؾذس ِب‬١‫ ع‬،ٍٞٛ‫خ ثًل غشبء خ‬١ٍ‫إرا وبٔذ اٌخ‬.‫اد اٌؼبسح‬ٌّٛ‫خ ِٓ ا‬٠‫خ اٌؾّب‬١ٍ‫عزفمذ اٌخ‬: ‫فقذاٌ انحًبٌت‬.1.‫اد‬ٌّٛ‫ط ا‬ٚ‫خش‬ٚ ‫ي‬ٛ‫ُ دخ‬١‫ب رٕظ‬ٙ١ٍ‫عززؼزس ػ‬: ٌ‫اخخالل انخىاص‬.2.‫اٌزغشة‬ٚ ‫خ ٌٍزٍف‬١ٍ‫بد اٌخ‬٠ٛ‫عززؼشع ِؾز‬: ‫حذيٍش انخهٍت‬.3.‫ اعزمجبي اإلشبساد ِٓ اٌخبسط‬ٍٝ‫عزفمذ اٌمذسح ػ‬: ‫فشم انخىاطم‬.4 ‫خ‬١‫ب األعبع‬ٙ‫ظبئف‬ٚ ‫خ ِٓ أداء‬١ٍ‫ٌٓ رزّىٓ اٌخ‬: ‫حىقف األَشطت انحٍىٌت‬.5 21.What do phospholipids do? Phospholipids perform the following functions: 1. Form the Cell Membrane: They make up the bilayer that forms the cell membrane. 2. Maintain Stability: Help maintain the stability and functionality of the membrane. 3. Selective Permeability: Control the passage of materials through the membrane, allowing some substances to pass while blocking others. 4. Membrane Organization: Help organize and distribute proteins within the membrane. :‫خ‬١ٌ‫ظبئف اٌزب‬ٌٛ‫ ا‬ٞ‫انفىسفىنٍبٍذاث رؤد‬.ٍٞٛ‫ْ اٌغشبء اٌخ‬ٛ‫ رى‬ٟ‫خ اٌز‬١‫رشىً اٌطجمخ اٌضٕبئ‬: ‫حكىٌٍ انغشبء انخهىي‬.1.ٗ‫ظبئف‬ٚٚ ‫ اعزمشاس اٌغشبء‬ٍٝ‫ اٌؾفبظ ػ‬ٟ‫رغبػذ ف‬: ‫انحفبظ عهى االسخقشاس‬.2.ٜ‫رّٕغ األخش‬ٚ ‫اد‬ٌّٛ‫س ثؼغ ا‬ٚ‫ش رغّؼ ثّش‬١‫ ؽ‬،‫اد ػجش اٌغشبء‬ٌّٛ‫س ا‬ٚ‫ ِش‬ٟ‫رزؾىُ ف‬: ‫انُفبرٌت االَخقبئٍت‬.3.‫ٕبد داخً اٌغشبء‬١‫ر‬ٚ‫غ اٌجش‬٠‫ص‬ٛ‫ر‬ٚ ُ١‫ رٕظ‬ٍٝ‫رؼًّ ػ‬: ‫انخًىقع فً انغشبء‬.4 22.Is osmosis active or passive? Explain Osmosis is a passive process. Explanation:  Osmosis occurs without the need for energy (ATP).  Water moves across a semi-permeable membrane from an area of low solute concentration to an area of high solute concentration, until equilibrium is reached. So, osmosis is a passive transport process.ً‫ اَخشبس سهب‬ٛ٘ ‫الَخشبس األسًىصي‬ :‫انخفسٍش‬ (ATP).‫ ؽبلخ‬ٌٝ‫ْ اٌؾبعخ إ‬ٚ‫ؾذس د‬٠ ‫االَخشبس األسًىصي‬   ‫اد‬ٌٍّٛ ‫ض ػب ٍي‬١‫ ِٕطمخ راد رشو‬ٌٝ‫اد اٌّزاثخ إ‬ٌٍّٛ ‫ض ِٕخفغ‬١‫ ِٓ ِٕطمخ راد رشو‬ٞ‫ٗ أزمبي اٌّبء ػجش غشبء شجٗ ٔفبر‬١‫زُ ف‬٠ .‫ضاد‬١‫ اٌزشو‬ٟ‫اصْ ف‬ٛ‫ؾذس ر‬٠ ٝ‫رٌه ؽز‬ٚ ،‫اٌّزاثخ‬.‫ األسًىصي هى عًهٍت َقم سهبٍت‬،‫نزا‬ 23.The sodium-potassium pump requires energy to move sodium and potassium ions across the cell membrane. Which of these describes the process used by the sodium-potassium pump? The process is active transport.  Active transport requires energy (ATP) to move sodium (Na) ions out of the cell and potassium (K) ions into the cell against their concentration gradients (from low to high concentration).‫انعًهٍت هً انضخ انُشظ‬ ‫خ ػذ رذسط‬١ٍ‫( داخً اٌخ‬K) َٛ١‫ربع‬ٛ‫ٔبد اٌج‬ٛ٠‫أ‬ٚ ‫خ‬١ٍ‫( خبسط اٌخ‬Na) َٛ٠‫د‬ٛ‫ٔبد اٌظ‬ٛ٠‫( ٌٕمً أ‬ATP) ‫زطٍت طبقت‬٠ ‫انضخ انُشظ‬  (‫ ِشرفغ‬ٌٝ‫ض ِٕخفغ إ‬١‫ض (ِٓ رشو‬١‫اٌزشو‬ 24.What of the following is the difference between active and passive transport? The difference between active and passive transport is: 1. Active Transport: o Requires energy (ATP). o Moves substances against the concentration gradient (from low to high concentration). o Example: Sodium-potassium pump. 2. Passive Transport: o Does not require energy. o Moves substances with the concentration gradient (from high to low concentration). o Example: Diffusion and osmosis. :ٛ٘ ً‫انفشق بٍٍ انُقم انُشظ وانُقم انسهب‬ :‫ انُقم انُشظ‬.1 (ATP).‫زطٍت طبقت‬٠ o ) ٌٟ‫ ػب‬ٌٝ‫ض ِٕخفغ إ‬١‫ض (ِٓ رشو‬١‫اد ػذ رذسط اٌزشو‬ٌّٛ‫ٕمً ا‬٠ o.‫انبىحبسٍىو‬-‫يضخت انظىدٌىو‬: ‫ ِضبي‬o :ً‫ انُقم انسهب‬.2.‫زطٍت ؽبلخ‬٠ ‫ ال‬o ) ‫ ِٕخفغ‬ٌٝ‫ إ‬ٌٟ‫ض ػب‬١‫ض (ِٓ رشو‬١‫اد يع رذسط اٌزشو‬ٌّٛ‫ٕمً ا‬٠ o.‫ األسًىصي‬ٚ ‫االَخشبس‬: ‫ ِضبي‬o  25.What factors affect the rate of diffusion across a cell membrane? Factors that affect the rate of diffusion across a cell membrane are: 1. Concentration: The greater the concentration gradient (the difference between high and low concentration), the faster the diffusion rate. 2. Temperature: Higher temperatures increase the movement of molecules, thus speeding up diffusion. 3. Molecule Size: Smaller molecules diffuse faster than larger ones. 4. Membrane Properties: The thickness or permeability of the membrane affects the rate of diffusion. 5. Medium: The type of medium (such as water or air) can influence the diffusion rate. :ٟ٘ ‫انعىايم انخً حؤثش عهى سشعت االَخشبس عبش غشبء انخهٍت‬.‫ صادد عشػخ االٔزشبس‬،)‫إٌّخفغ‬ٚ ٌٟ‫ض اٌؼب‬١‫ٓ اٌزشو‬١‫ض (اٌفشق ث‬١‫وٍّب صاد رذسط اٌزشو‬: ‫انخشكٍض‬.1.‫بدح عشػخ االٔزشبس‬٠‫ ص‬ٌٟ‫ثبٌزب‬ٚ ،‫ئبد‬٠‫بدح عشػخ ؽشوخ اٌغض‬٠‫ ص‬ٌٝ‫ إ‬ٞ‫بدح دسعخ اٌؾشاسح رؤد‬٠‫ص‬: ‫دسجت انحشاسة‬.2.‫شح‬١‫ئبد اٌىج‬٠‫شح رٕزشش أعشع ِٓ اٌغض‬١‫ئبد اٌظغ‬٠‫اٌغض‬: ‫حجى انجضٌئبث‬.3.‫ عشػخ االٔزشبس‬ٍٝ‫ؤصش ػ‬٠ ٗ‫ز‬٠‫ ٔفبر‬ٜ‫ ِذ‬ٚ‫عّه اٌغشبء أ‬: ‫خظبئض انغشبء‬.4.‫ عشػخ االٔزشبس‬ٍٝ‫ؤصش ػ‬٠ ْ‫ّىٓ أ‬٠ )‫اء‬ٌٛٙ‫ ا‬ٚ‫عؾ (ِضً اٌّبء أ‬ٌٛ‫ع ا‬ٛٔ (‫انىسٍظ (انًبدة‬.5 26.What increases the rate of diffusion of a molecule into a cell membrane? Answer and Explanation: Factors that increase the rate of diffusion of a molecule into a cell membrane: 1. Increased Concentration Gradient: o Answer: The greater the difference between the concentration inside and outside the cell, the faster the diffusion rate. o Explanation: A larger concentration difference drives molecules to move more quickly from high to low concentration. 2. Increased Temperature: o Answer: Higher temperatures increase the movement of molecules. o Explanation: At higher temperatures, molecules move faster, which speeds up the diffusion process. 3. Smaller Molecule Size: o Answer: Smaller molecules diffuse faster. o Explanation: Smaller molecules move more easily across the cell membrane compared to larger ones. 4. Increased Surface Area: o Answer: A larger surface area increases the rate of diffusion. o Explanation: A larger surface area provides more space for substances to diffuse across the membrane  :‫انعىايم انخً حضٌذ يٍ يعذل اَخشبس انجضٌئبث عبش غشبء انخهٍت‬ :‫صٌبدة حذسج انخشكٍض‬.1.‫ صادد عشػخ االٔزشبس‬،‫ب‬ٙ‫خبسع‬ٚ ‫خ‬١ٍ‫ض داخً اٌخ‬١‫ٓ اٌزشو‬١‫وٍّب صاد اٌفشق ث‬: ‫ اإلجببت‬o ‫ض‬١‫ إٌّطمخ راد اٌزشو‬ٌٝ‫ إ‬ٌٟ‫ض اٌؼب‬١‫ئبد ِٓ إٌّطمخ راد اٌزشو‬٠‫ؼضص ؽشوخ اٌغض‬٠ ‫ض‬١‫ اٌزشو‬ٟ‫اٌفشق األوجش ف‬: ‫ انخفسٍش‬o.‫إٌّخفغ ثشىً أعشع‬ :‫صٌبدة دسجت انحشاسة‬.2.‫ئبد‬٠‫ذ ِٓ ؽشوخ اٌغض‬٠‫ رض‬ٍٝ‫اٌؾشاسح األػ‬: ‫ اإلجببت‬o.‫ذ ِٓ ِؼذي االٔزشبس‬٠‫ض‬٠ ‫ ِّب‬،‫ئبد ثشىً أعشع‬٠‫ رزؾشن اٌغض‬،‫ػٕذ اسرفبع دسعخ اٌؾشاسح‬: ‫ انخفسٍش‬o :‫قهٍم حجى انجضٌئبث‬.3.‫انجضٌئبث انظغٍشة حُخشش أسشع‬: ‫ اإلجببت‬o.‫شح‬١‫ئبد اٌىج‬٠‫خ ِمبسٔخ ثبٌغض‬١ٍ‫شح رزؾشن ثشىً أعشع ػجش غشبء اٌخ‬١‫ئبد اٌظغ‬٠‫اٌغض‬: ‫ انخفسٍش‬o :‫صٌبدة يسبحت انسطح‬.4.‫صٌبدة يسبحت انسطح حسهى فً صٌبدة سشعت االَخشبس‬: ‫ اإلجببت‬o ‫اد ًٌلٔزشبس ػجش اٌغشبء‬ٌٍّٛ ‫فش ِغبؽخ أوجش‬ٛ‫ِغبؽخ عطؼ أوجش ر‬: ‫ انخفسٍش‬o 27.What 3 factors increase the rate of diffusion? Three factors that increase the rate of diffusion: 1. Increased Concentration Gradient: The greater the difference between the concentration inside and outside the cell, the faster the diffusion rate. 2. Increased Temperature: Higher temperatures increase the movement of molecules, speeding up diffusion. 3. Smaller Molecule Size: Smaller molecules diffuse faster than larger ones :‫ثالثت عىايم حضٌذ يٍ يعذل االَخشبس‬.‫ صادد عشػخ االٔزشبس‬،‫خ‬١ٍ‫خبسط اٌخ‬ٚ ً‫ض داخ‬١‫ٓ اٌزشو‬١‫ وٍّب صاد اٌفشق ث‬: ‫ صٌبدة حذسج انخشكٍض‬.1.‫غشع االٔزشبس‬٠ ‫ ِّب‬،‫ئبد‬٠‫ذ ِٓ ؽشوخ اٌغض‬٠‫ رض‬ٍٝ‫ دسعبد اٌؾشاسح األػ‬: ‫ صٌبدة دسجت انحشاسة‬.2.‫ئبد األوجش‬٠‫ئبد األطغش رٕزشش أعشع ِٓ اٌغض‬٠‫ اٌغض‬: ‫ حقهٍم حجى انجضٌئبث‬.3 28.What 3 factors affect the rate of diffusion across the plasma membrane? Three factors that affect the rate of diffusion across the plasma membrane: 1. Concentration Gradient: The difference in concentration inside and outside the cell; a larger gradient increases the diffusion rate. 2. Temperature: Higher temperatures increase the movement of molecules, speeding up diffusion. 3. Molecule Size: Smaller molecules diffuse faster across the plasma membrane compared to larger molecules  :ً‫ثالثت عىايم حؤثش عهى يعذل االَخشبس عبش انغشبء انبالصي‬.‫ش ِٓ عشػخ االٔزشبس‬١‫ذ اٌزذسط اٌىج‬٠‫ض‬٠ ‫ش‬١‫ ؽ‬،‫اٌخبسط‬ٚ ً‫ٓ اٌذاخ‬١‫ض ث‬١‫ اٌزشو‬ٟ‫اٌفشق ف‬: ‫ حذسج انخشكٍض‬.1.‫غشع االٔزشبس‬٠ ‫ ِّب‬،‫ئبد‬٠‫ذ ِٓ ؽشوخ اٌغض‬٠‫خ رض‬١ٌ‫اٌؾشاسح اٌؼب‬: ‫ دسجت انحشاسة‬.2.‫ئبد األوجش‬٠‫ ِمبسٔخ ثبٌغض‬ِٟ‫ئبد األطغش رٕزشش ثغشػخ أوجش ػجش اٌغشبء اٌجًلص‬٠‫اٌغض‬: ‫ حجى انجضٌئبث‬.3 29.We graphed dn/dt as a function of dC/dx. What is the slope of this line? What do increases or decreases in the slope mean biologically? Answer: 1. Slope of the Line: o The line represents Fick's law of diffusion, where dn/dt is the rate of diffusion and dC/dx is the concentration gradient. o The slope represents the diffusion coefficient (D), which determines how fast molecules diffuse across the medium. 2. Increases or Decreases in the Slope: o Increase in the slope means the diffusion coefficient (D) has increased, indicating that diffusion is faster. Biologically, this could mean an improvement in membrane transport efficiency or an increase in temperature that enhances molecular movement. o Decrease in the slope means the diffusion coefficient (D) has decreased, indicating slower diffusion. Biologically, this could suggest unfavorable conditions, such as lower temperature or barriers to diffusion across the membrane. Biological Interpretation:  An increase in the slope means faster diffusion, which is beneficial for biological processes like metabolism or signal transmission.  A decrease in the slope means slower diffusion, which could result from pathological conditions or disruptions in membrane function. :‫انسؤال‬ ‫خ؟‬١‫ع‬ٌٛٛ١‫خ اٌج‬١‫ً ِٓ إٌبؽ‬١ٌّ‫ ا‬ٟ‫ إٌمظبْ ف‬ٚ‫بداد أ‬٠‫ٗ اٌض‬١ٕ‫ رؼ‬ٞ‫ِب اٌز‬ٚ ‫ً ٘زٖ اٌخؾ؟‬١ِ ٛ٘ ‫ ِب‬،dC/dx ‫وذاٌخ ٌـ‬dn/dt ُ‫إرا لّٕب ثشع‬ :‫اإلجببت‬ (Slope of the Line):‫ يٍم انخظ‬.1.‫ض‬١‫ اٌزشو‬ٟ‫ اٌزذسط ف‬ٛ٘dC/dx ٚ ‫ّضً ِؼذي االٔزشبس‬٠dn/dt ‫ش‬١‫ ؽ‬،‫نالَخشبس‬ick ‫ انخظ هى حًثٍم نًعبدنت ف‬o ‫ئبد‬٠‫ عشػخ أزشبس اٌغض‬ٜ‫ؾذد ِذ‬٠ ‫(٘زا اٌضبثذ‬Diffusion coefficient, D). ‫ؼجش ػٓ انثببج االَخشبسي‬٠ ً١ٌّ‫ ا‬o.‫عؾ‬ٌٛ‫ػجش ا‬ (Changes in the slope):‫ انضٌبدة أو انُقظبٌ فً انًٍم‬.2 ٌٝ‫ش رٌه إ‬١‫ش‬٠ ‫ لذ‬،‫ًب‬١‫ع‬ٌٛٛ١‫ ث‬.‫ أْ االٔزشبس أطجؼ أعشع‬ٌٝ‫ش إ‬١‫ش‬٠ ‫ ِّب‬،‫( صاد‬D) ‫ أْ انثببج االَخشبسي‬ٟٕ‫ صٌبدة انًٍم رؼ‬o.‫خ‬١‫ئ‬٠‫ رؼضص اٌؾشوخ اٌغض‬ٟ‫ دسعخ اٌؾشاسح اٌز‬ٟ‫بدح ف‬٠‫ ص‬ٚ‫ وفبءح إٌمً ػجش اٌغشبء أ‬ٟ‫بدح ف‬٠‫ص‬  ‫ش‬١‫ش‬٠ ‫ لذ‬،‫ًب‬١‫ع‬ٌٛٛ١‫ ث‬.‫ أخفبع عشػخ االٔزشبس‬ٌٝ‫ش إ‬١‫ش‬٠ ‫ ِّب‬،‫( أخفغ‬D) ‫ أْ انثببج االَخشبسي‬ٟٕ‫ؼ‬٠ ‫َقظبٌ انًٍم‬ o.‫ اٌغشبء‬ٍٝ‫أغ االٔزشبس ػ‬ِٛ ُ‫ رشاو‬ٚ‫خ ِضً أخفبع دسعخ اٌؾشاسح أ‬١‫ار‬ِٛ ‫ش‬١‫ف غ‬ٚ‫ ظش‬ٌٝ‫رٌه إ‬ :ً‫انخفسٍش انبٍىنىج‬.‫ ٔمً اإلشبساد‬ٚ‫غ أ‬٠‫خ ِضً األ‬٠ٛ١‫بد اٌؾ‬١ٍّ‫ اٌؼ‬ٟ‫ذًا ف‬١‫ْ ِف‬ٛ‫ى‬٠ ْ‫ّىٓ أ‬٠ ‫ ِّب‬،‫اد‬ٌٍّٛ ‫ اَخشب ًسا أسشع‬ٟٕ‫ً رؼ‬١ٌّ‫بدح ا‬٠‫ص‬ .ٍٞٛ‫ظبئف اٌغشبء اٌخ‬ٚ ٟ‫ اػطشاثبد ف‬ٚ‫خ أ‬١‫ف ِشػ‬ٚ‫غخ ٌظش‬١‫ْ ٔز‬ٛ‫ى‬٠ ‫ ِّب لذ‬،‫ اَخشبس أبطأ‬ٌٝ‫ش إ‬١‫ش‬٠ ً١ٌّ‫ٔمظبْ ا‬  30.Now assume the concentration gradient is a constant. How does the rate of diffusion (dn/dt) change with the surface area (A) of the cell and the permeability (P) of the diffusing molecule? Graph dn/dt as a function of A or P and describe the function. Answer: When the concentration gradient is constant, the rate of diffusion (dn/dt) depends on the surface area (A) and the permeability (P) of the membrane to the diffusing molecule. 1. Rate of Diffusion (dn/dt) and Surface Area (A):  Relationship: If the surface area (A) of the cell increases, the rate of diffusion increases directly.  Explanation: Increasing surface area provides more space for molecules to diffuse across the membrane, leading to a higher rate of diffusion.  Graph: The graph would be a straight line, showing that the rate of diffusion increases proportionally with surface area. Mathematical Function: dndt∝A\frac{dn}{dt} \propto Adtdn∝A (Rate of diffusion is directly proportional to surface area) 2. Rate of Diffusion (dn/dt) and Permeability (P):  Relationship: If the permeability (P) of the membrane to the diffusing molecule increases, the rate of diffusion also increases directly.  Explanation: Increased permeability means the molecule can pass through the membrane more easily, speeding up diffusion.  Graph: The graph would also be a straight line, showing that the rate of diffusion increases with permeability. Mathematical Function: ‫‪dndt∝P\frac{dn}{dt} \propto Pdtdn∝P‬‬ ‫)‪(Rate of diffusion is directly proportional to permeability‬‬ ‫‪Biological Interpretation:‬‬ ‫‪‬‬ ‫‪Increasing surface area (A) can occur in cells with extensions like microvilli or cells with a‬‬ ‫‪larger surface for absorption or exchange.‬‬ ‫‪‬‬ ‫‪Increasing permeability (P) can occur when there are transport proteins or channels in the‬‬ ‫‪membrane that facilitate the movement of molecules.‬‬ ‫‪Conclusion:‬‬ ‫‪‬‬ ‫‪The graph of the rate of diffusion (dn/dt) vs. surface area (A) and permeability (P) would be a‬‬ ‫‪straight, upward-sloping line, as both factors positively affect the rate of diffusion‬‬ ‫انسؤال‪:‬‬ ‫افزشع أْ رذسط اٌزشو‪١‬ض صبثذ‪.‬و‪١‬ف ‪٠‬زغ‪١‬ش ِؼذي االٔزشبس )‪ِ (dn/dt‬غ ِغبؽخ اٌغطؼ )‪ٌٍ (A‬خٍ‪١‬خ ‪َ ٚ‬فبرٌت )‪ (P‬اٌغض‪ٞ‬ء اٌّزٕمً؟ اسعُ‬ ‫‪dn/dt‬وذاٌخ ٌـ ‪A‬أ‪ٚٚP ٚ‬طف اٌ‪ٛ‬ظ‪١‬فخ‪.‬‬ ‫اإلجببت‪:‬‬ ‫ػٕذِب ‪٠‬ى‪ ْٛ‬رذسط اٌزشو‪١‬ض صبثزًب‪ ،‬فئْ ِؼذي االٔزشبس )‪٠ (dn/dt‬ؼزّذ ػٍ‪ ٝ‬يسبحت انسطح )‪َ ٚ (A‬فبرٌت انغشبء )‪ٌٍ (P‬غض‪ٞ‬ء اٌّزٕمً‪.‬‬ ‫‪1.‬يعذل االَخشبس )‪ (dn/dt‬وانعالقت يع يسبحت انسطح‪(A):‬‬ ‫انعالقت ‪:‬إرا صادد يسبحت انسطح )‪ٌٍ(A‬خٍ‪١‬خ‪ ،‬ع‪١‬ضداد ِؼذي االٔزشبس ثشىً ِجبشش‪.‬‬ ‫‪‬‬ ‫انخفسٍش ‪:‬ص‪٠‬بدح ِغبؽخ اٌغطؼ ر‪ٛ‬فش ِغبؽخ أوجش ٌٍغض‪٠‬ئبد ًٌلٔزشبس ػجش اٌغشبء‪ِّ ،‬ب ‪٠‬ؤد‪ ٞ‬إٌ‪ ٝ‬ص‪٠‬بدح ف‪ِ ٟ‬ؼذي االٔزشبس‪.‬‬ ‫‪‬‬ ‫انشسى انبٍبًَ ‪٠:‬ى‪ ْٛ‬اٌشعُ اٌج‪١‬بٔ‪ ٟ‬ػجبسح ػٓ خظ يسخقٍى‪ ،‬ؽ‪١‬ش أْ ِؼذي االٔزشبس ‪٠‬ضداد ثشىً ِزٕبعت ِغ ص‪٠‬بدح ِغبؽخ‬ ‫‪‬‬ ‫اٌغطؼ‪.‬‬ ‫انذانت انشٌبضٍت‪:‬‬ ‫‪dndt∝A\frac{dn}{dt} \propto Adtdn∝A‬‬ ‫ِؼذي االٔزشبس ‪٠‬زٕبعت ؽشد‪ً٠‬ب ِغ ِغبؽخ اٌغطؼ‬ ‫‪2.‬يعذل االَخشبس )‪ (dn/dt‬وانعالقت يع انُفبرٌت‪(P):‬‬ ‫انعالقت ‪:‬إرا صادد َفبرٌت اٌغشبء )‪ٌٍ (P‬غض‪ٞ‬ء اٌّزٕمً‪ ،‬ع‪١‬ضداد ِؼذي االٔزشبس أ‪٠‬ؼً ب ثشىً ِجبشش‪.‬‬ ‫‪‬‬ ‫انخفسٍش ‪:‬ص‪٠‬بدح إٌفبر‪٠‬خ رؼٕ‪ ٟ‬أْ اٌغض‪ٞ‬ء ‪ّ٠‬ىٕٗ ػج‪ٛ‬س اٌغشبء ثغ‪ٌٛٙ‬خ أوجش‪ِّ ،‬ب ‪٠‬ض‪٠‬ذ ِٓ عشػخ االٔزشبس‪.‬‬ ‫‪‬‬ ‫ؼب ػجبسح ػٓ خظ يسخقٍى‪ ،‬ؽ‪١‬ش ‪٠‬ضداد ِؼذي االٔزشبس ِغ ص‪٠‬بدح إٌفبر‪٠‬خ‪.‬‬ ‫انشسى انبٍبًَ ‪٠:‬ى‪ ْٛ‬اٌشعُ اٌج‪١‬بٔ‪ ٟ‬أ‪ً ٠‬‬ ‫‪‬‬  ‫انذانت انشٌبضٍت‪:‬‬ ‫‪dndt∝P\frac{dn}{dt} \propto Pdtdn∝P‬‬ ‫ِؼذي االٔزشبس ‪٠‬زٕبعت ؽشد‪ً٠‬ب ِغ إٌفبر‪٠‬خ‬ ‫انخفسٍش انبٍىنىجً‪:‬‬ ‫صٌبدة يسبحت انسطح )‪(A‬لذ رؾذس ف‪ ٟ‬خًل‪٠‬ب أوضش رّذدًا أ‪ ٚ‬خًل‪٠‬ب رؾز‪ ٞٛ‬ػٍ‪ ٝ‬اِزذاداد ِضً اٌشؼ‪١‬شاد اٌذل‪١‬مخ (اٌّ‪١‬ىش‪ٚ‬ف‪).ٍٍٟ١‬‬ ‫‪‬‬ ‫صٌبدة انُفبرٌت )‪(P‬لذ رؾذس ف‪ ٟ‬ؽبٌخ ‪ٚ‬ع‪ٛ‬د ثش‪ٚ‬ر‪ٕ١‬بد ٔمً أ‪ ٚ‬لٕ‪ٛ‬اد ف‪ ٟ‬اٌغشبء اٌخٍ‪ ٞٛ‬رغ‪ِ ًٙ‬ش‪ٚ‬س اٌغض‪٠‬ئبد‪.‬‬ ‫‪‬‬ ‫انخخبو‪:‬‬ ‫انشسى انبٍبًَ نًعذل االَخشبس )‪ (dn/dt‬ببنُسبت نًسبحت انسطح )‪ٚ (A‬إٌفبر‪٠‬خ )‪٠ (P‬ى‪ ْٛ‬خ ً‬ ‫طب يسخقٍ ًًب طبعذًا‪ ،‬ألْ وًل‬ ‫‪‬‬ ‫اٌؼبٍِ‪٠ ٓ١‬ؤصشاْ ثشىً ؽشد‪ ٞ‬ػٍ‪ ٝ‬عشػخ االٔزشبس‪.‬‬