Download Semmelweis Entrance Exam Medicine: Biology Questions and Answers and more Exams Medicine in PDF only on Docsity!
Biology Questions And Answers
What are carbohydrates and lipids? - correct answer Organic compounds that are mostly composed of three types of atom; carbon, hydrogen and oxygen What do carbohydrates do? - correct answer provide energy, in the form of sugars like glucose and fructose, but they also make up structures like cellulose, which form the cell wall of plant cells What type of carbohydrate is the most important source of energy? - correct answer mono-, di- and poly-saccharides What are mono and disaccharides? - correct answer polar and soluble in water What are polysaccharides? - correct answer Macromolecules resulting from polymerization (condensation) of sugars and are not soluble in water Examples of monosaccharides - correct answer ribose, glucose, fructose, galactose
Biology Questions And Answers
What forms a disaccharide? - correct answer two monosaccharides linked together by condensation reactions with glycosidic bonds releasing one H2O molecule Alpha glucose structure - correct answer Beta glucose structure - correct answer Examples of Polysaccharides - correct answer cellulose, glycogen and starch Monomer of Sucrose - correct answer glucose and fructose monomer of maltose - correct answer glucose and glucose monomer of lactose - correct answer glucose and galactose monomer of starch - correct answer glucose
Biology Questions And Answers
What is fructose? - correct answer a sugar found in fruit and honey Main characteristic of lipids? - correct answer little to no affinity to water, mostly hydrophobic What are the simple forms of lipids? - correct answer fat, oil and wax What are lipids characteristics in different solvents? - correct answer they are non-polar and insoluble in water, but soluble in organic solvents What are triglycerides? - correct answer the main group of lipids. They are formed by condensation reactions between one glycerol and three fatty acids, creating ester bonds What are the main types of triglycerides? - correct answer fats and oils. Fats are solid and oil liquid at room temp
Biology Questions And Answers
What are fatty acids? - correct answer carboxylic acids, possessing a -COOH functional group What are the two basic forms of fatty acids? - correct answer saturated and unsaturated What differs saturated from unsaturated fatty acids? - correct answer Unsaturated fatty acids have double bonds; a monounsaturated having one, whereas a polyunsaturated having multiple What are cis and trans isomers? - correct answer cis having the double bond elements on the same side, trans on opposite Benefit of lipids over carbohydrates? - correct answer Lipids have a higher energy content and can act as thermal insulators What is the primary protein structure? - correct answer the number and sequence of amino acids in a polypeptide
Biology Questions And Answers
What are hydrogen bonds? - correct answer a special type of dipole-dipole attraction between molecules, not a covalent bond to a hydrogen atom. It results from the attractive force between a hydrogen atom covalently bonded to a very electronegative atom such as a N, O, or F atom and another very electronegative atom Why is DNA antiparallel? - correct answer so that the paired bases can face each other what is mRNA? - correct answer Messenger RNA: Encodes amino acid sequence of a polypeptide What is tRNA? - correct answer transfer RNA. It carries amino acids around during translation. What is rRNA? - correct answer Ribosomal RNA. with ribosomal proteins, makes up the ribosomes, the organelles that translate the mRNA
Biology Questions And Answers
what is snRNA? - correct answer small nuclear RNA. with proteins, forms complexes that are used in RNA processing in eukaryotes What are enzymes? - correct answer biological catalysts. They are globular proteins that can speed up a biochemical reaction. Alternative pathway What is glycolysis? - correct answer the breakdown of glucose by enzymes, releasing energy and pyruvic acid. What is the kreb's cycle? - correct answer second stage of cellular respiration, in which pyruvic acid is broken down into carbon dioxide in a series of energy-extracting reactions What is the mechanism of ATP production in the mitochondria? - correct answer located in the inner mitochondrial membrane, allows the protons to diffuse back across the membrane to the matrix. ATP synthase uses the energy that the protons release as they diffuse down the concentration gradient to produce ATP
Biology Questions And Answers
what is the nucleus - correct answer A part of the cell containing DNA and RNA and responsible for growth and reproduction What are chromosomes? - correct answer Chromosomes are long, thin strings composed of DNA and proteins which carry genes. What is the function of the endoplasmic reticulum? - correct answer Modifies, packages, and transports proteins What is the function of the golgi apparatus? - correct answer sorts and modifies proteins that have arrived from the rough ER What is the function of ribosomes? - correct answer protein synthesis by translating mRNA What is the cytoskeleton? - correct answer a microscopic network of protein filaments and tubules in the cytoplasm of many living cells, giving them shape and coherence.
Biology Questions And Answers
What is exocytosis? - correct answer a process by which the contents of a cell vacuole are released to the exterior through fusion of the vacuole membrane with the cell membrane. What is endocytosis? - correct answer the taking in of matter by a living cell by invagination of its membrane to form a vacuole What is the function of a cell membrane? - correct answer The cell membrane regulates what enters and leaves the cell and also protects and supports the cell Cell membrane diagram - correct answer Describe the process of mitosis - correct answer - Start with: Diploid, 2N
- Interphase: DNA replication = Dipoid, 4N
- Prophase: Condensation of chromatin, appearance of sister chromatids
- Metaphase: Sister chromatids align
- Anaphase: Sister chromatids separate, centromeres divide
Biology Questions And Answers
Example of prokaryotic cell - correct answer E. coli Example of eukaryotic cell - correct answer plant and animal cells What is the structure of eukaryotic cells? - correct answer What is the structure of a virus? - correct answer A typical virus is composed of a core of DNA or RNA surrounded by a protein coat What is transformation? - correct answer uptake of DNA from environment What is conjugation? - correct answer A process in which 2 organisms exchange genetic material What are all the parts to the digestive system? - correct answer
Biology Questions And Answers
How does absorption occur? - correct answer diffusion, facilitated diffusion, osmosis, active transport How does absorption work? - correct answer - food molecules are absorbed into the blood or the lymph. To be absorbed in the body the molecules need to pass into the capillaries or the villus. Fats absorb into the lymph
- Substances to be absorbed move from the lumen into the epithelial villi
- Amino acids and monosaccharides move from the villi into capillaries and monoglycerides move into the lacteals What are some of the digestive enzymes? - correct answer -trypsinogen and chymotrypsin (breaks down proteins) -amylase breaks down starches and sugars -lipase breaks down fats What are the parts of the respiratory system? - correct answer
Biology Questions And Answers
What is blood? - correct answer fluid connective tissue What does blood contain? - correct answer Nutrients such as glucose, antibodies, carbon dioxide, heat, oxygen, urea and hormones What are the different cell types? - correct answer Prokaryotic and Eukaryotic What is the process of cellular immune response? - correct answer the immune system's third line of defense, involving the attack of pathogens by T cells What are the three lines of defense? - correct answer First line: Natural barriers: Skin and mucous membranes Second line: Inflammation Third line: Adaptive (acquired) immunity How does blood clotting occur? - correct answer Clotting seals damaged vessels to prevent pathogenic entry
- Injured cells and platelets release clotting factors
- These factors convert prothrombin into thrombin
Biology Questions And Answers
- Thrombin converts fibrinogen (soluble) into fibrin (insoluble)
- Fibrin forms a mesh of fibres that block the injured site - Clotting factors also cause platelets to become sticky and form a solid plug (called a clot), sealing the wound - This process of events is called a coagulation cascade
- Clot formation in coronary arteries lead to heart attacks What is innate immunity? - correct answer Nonspecific protection against foreign substances indiscriminantly All cells but lymphocytes What is the humoral immune response? - correct answer The humoral immune response targets pathogens circulating in "humors," or extracellular fluids, such as blood and lymph. Antibodies target invading pathogens for destruction via multiple defense mechanisms, including neutralization, opsonization, and activation of the complement system. Patients that are impaired in the production of antibodies suffer from severe and frequent infections by common pathogens and unusual pathogens What are muscles? - correct answer tissues or fibers that cause movement of body parts and organs
Biology Questions And Answers
Parts of the female reproductive system - Describe the ovarian cycle - correct answer Eggs are formed through meiosis in ovaries 1 matures enough to be released into fallopian tubes (halfway through monthly cycle) Corpus luteum where egg used to be disintegrates unless fertilized What causes ovulation? - correct answer surge of LH What causes menstruation? - correct answer drop in estrogen and progesterone What are the pituitary gland hormones and what are their functions? - correct answer The pituitary gland is about the size of a pea. It is located in the brain, and sits just behind the bridge of the nose. The pituitary gland is called the master gland of the endocrine system. This is because it controls many other hormone glands in the body
Biology Questions And Answers
What are the adrenal gland hormones and what are their functions? - correct answer The adrenal cortex—the outer part of the gland—produces hormones that are vital to life, such as cortisol (which helps regulate metabolism and helps your body respond to stress) and aldosterone (which helps control blood pressure) What are the thyroid gland hormones and what are their functions? - correct answer The function of the thyroid gland is to take iodine, found in many foods, and convert it into thyroid hormones: thyroxine and triiodothyronine Describe the autonomic nervous system - correct answer The autonomic nervous system is the motor subdivision of the parasympathetic nervous system that controls body activities automatically. The ANS is composed of a specialized group of neurons that regulate the cardiac muscle, smooth muscles, and gland. The relative stability of the body is due to the ANS. What are spinal reflexes? - correct answer simple pathways in the nervous system that rapidly generate muscle contractions
