1st year university Cell Biology Actual Exam Questions With Correct Detailed Answers A+ Score.

Small unit bound by a plasma membrane - correct answer Cell Osmosis - correct answer Movement of water across as semipermeable membrane from a hypotonic solution to a hypertonic solution or low osmolarity to high osmolarity or low osmotic pressure to high osmotic pressure HIGH CONCENTRATION OF WATER TO LOW CONCENTRATION OF WATER Smallest functional component of multicellular organism - correct answer Cell All living entities must: Harness Energy Respire Grow and develop Reproduce Respond to stimuli - correct answer What must living entities do? Robert Hooke in 1665 using cork - correct answer Who coined the term "Cell" and when? A scientist that invented 25 different hand made microscopes. Observed unicellular microorganisms and also blood cells in vertebrates. Who and When? - correct answer Anton Van Leeuwenhoek 1673 A scientist that concluded "all plant parts are made of cells". Who and When? - correct answer Matthias schleiden 1838 A scientist that concluded "all animal tissues are made of cells".Who and When? - correct answer Theodor Schwann 1839 Who and When did not accept the popular theory of spontaneous generation. Concluded " Cells arise from pre-existing cells" "omnis cellula e cellula" - correct answer Rudolf Virchow 1858 The cell theory postulate - correct answer -All organisms consist of one or more cells. -The cell is the basic structural unit of all organisms. -Cells arise from pre-existing cells "omnis cellula e cellula" -Cell smallest living entity -Cells are the basis of reproduction Microscopy - correct answer Was essential in the development of the cell theory. Subtypes of light microscopes - correct answer Brightfield Phase contrast Differential interference Contrast Confocal Fluorescence Subtypes of electron microscopy (EM) - correct answer Scanning EM Transmission How do cells differ - correct answer Size Shape/Structure Function Erythrocyte - correct answer Red blood cell. Diameter 8µm lipid bilayer and selectively permeable - correct answer The cell surface membrane What is a plasma membrane made of? - correct answer -Lipids -PS,PE,PC -Glycerol -Proteins integral and peripheral membrane proteins -Carbohydrates -Glycoproteins, glycolipids -Peptidoglycans and glycosaminoglycans What makes the plasma membrane semipermeable? - correct answer As it is amphiphatic (Hydrophobic tail and hydrophilic head) Cell wall in plants - correct answer composed of cellulose Cellulose - correct answer Complex carbohydrate can not be digested by animals as we don't have cellulase Bacterial cell wall (prokaryotes) - correct answer Composed of peptidoglycans Surrounded by gelatinous polysaccharide layer "slime layer" -glycocalyx Glycocalyx - correct answer component of the capsule surrounding the cell wall "slime layer" Cell surface appendages - correct answer Villi/microvilli Cilia Flagella Gram's Stain - correct answer Gram positive bacteria Gram negative bacteria Gram positive bacteria - correct answer Have single layer in cell wall Gram negative bacteria - correct answer Have several layers in cell wall What is the purpose of: Villi/microvilli - correct answer To increase the cell's surface area What is the purpose of: Cilia - correct answer to move the extracellular fluid (ECF) What is the purpose of: Flagella - correct answer To assist in cell movement Nucleus - correct answer Contains the blueprint for proteins Has chromosomes Has nucleolus Separated from cytoplasm by double membrane (nuclear envelope) contains nuclear pores Nucleolus - correct answer Within the nucleus Has no membrane Site of transcription and ribosome synthesis Centrioles - correct answer 9 pairs of triplet microtubules. specialised microtubules Found adjacent to nucleus in animal cells only. perpendicular pair of centrioles for the "centrosome". organise spindle mitosis and meiosis. Centrosome - correct answer In many cells the centrosome is near the nucleus. Two perpendicular centrioles In cell division each cell gets only one pair of centrioles (one centrosome). Forms the mitotic spindle Synthetics organelles - correct answer Chloroplasts Ribosomes Endoplasmic Reticulum Golgi apparatus Site of photosynthesis - correct answer Chloroplasts Site of translation of proteins - correct answer Ribosomes Site of protein and lipid synthesis - correct answer Endoplasmic reticulum Site of protein processing, sorting and secretion - correct answer Golgi apparatus Mitochondrion - correct answer Bound by a double membrane Inner and outer membranes separated by inter membrane space The inner membrane is folded into "cristea" The inside of the mitochondrion is he "matrix" Has mitochondrial DNA An organelle with only maternal DNA - correct answer Mitochondrion organelles bound by double membrane - correct answer Chloroplasts Mitochondrion Nucleus Ribosomes - correct answer Organelle containing two subunits each is a complex of rRNA and proteins The larger subunit is enzymatic they exist in two sizes 40S+60S (80S in eukaryotes) 30S+50S (70S in prokaryotes) (numbers do not sum up) Polysomes - correct answer Several ribosomes translating the same mRNA template Endoplasmic reticulum (ER) - correct answer organelle with highly convoluted membrane system from the nucleus to the plasma membrane What is the difference between rough and smooth endoplasmic reticulum? - correct answer Smooth ER-site of lipid synthesis Rough ER- site of protein synthesis (rough as it has ribosomes attached to the convoluted membrane. The synthesis occurs in the lumen of the cisternae Golgi apparatus - correct answer A synthetic organelle series of specialised stacked cisternae which proteins and lipids are processed before secretion. molecules enter from the cis face and exit from the trans face of the GA Enzymes in the GA can add carbohydrates to lipids or proteins glycolipids and glycoproteins respectively Hydrophilic - correct answer polar compound that is attracted to water Hydrophobic - correct answer A compound that does not react with water Two major membrane lipids - correct answer Glycerophospholipids Sphingolipids NEVER forget cholesterol Glycerophospholipids - correct answer phosphatidylinositol phosphatidylcholine phosphatidylethanolamine phosphatidylserine Sphingolipids- serine linker - correct answer cerebroside sphingomyelin GM1 ganglioside Glycolipids - correct answer cerebroside GM1 ganglioside Types phospholipids - correct answer