Wednesday, October 16, 2013

Animal CellPlant Cell
Cell wall:AbsentPresent (formed of cellulose)
Shape:Round (irregular shape)Rectangular (fixed shape)
Vacuole:One or more small vacuoles (much smaller than plant cells).One, large central vacuole taking up 90% of cell volume.
Centrioles:Present in all animal cellsOnly present in lower plant forms.
Chloroplast:Animal cells don't have chloroplastsPlant cells have chloroplasts because they make their own food
Endoplasmic Reticulum (Smooth and Rough):PresentPresent
Golgi Apparatus:PresentPresent
Plasma Membrane:only cell membranecell wall and a cell membrane
Microtubules/ Microfilaments:PresentPresent
Flagella:May be found in some cellsMay be found in some cells
Lysosomes:Lysosomes occur in cytoplasm.Lysosomes usually not evident.
Cilia:PresentIt is very rare

Comparison chart

Definition:A type of cellular reproduction in which the number of chromosomes are reduced by half through the separation of homologous chromosomes, producing two haploid cells.A process of asexual reproduction in which the cell divides in two producing a replica, with an equal number of chromosomes in each resulting diploid cell.
Function:sexual reproductionCellular Reproduction & general growth and repair of the body
Type of Reproduction:SexualAsexual
Occurs in:Humans, animals, plants, fungiall organisms
Crossing Over:Yes, mixing of chromosomes can occur.No, crossing over cannot occur.
Pairing of Homologs:YesNo
Number of Divisions:21
Number of Daughter Cells produced:4 haploid cells2 diploid cells
Chromosome Number:Reduced by halfRemains the same
Steps:The steps of meiosis are Interphase, Prophase I, Metaphase I, Anaphase I, Telophase I, Prophase II, Metaphase II, Anaphase II and Telophase II.The steps of mitosis are Interphase, Prophase, Metaphase, Anaphase, Telophase and Cytokinesis
Karyokinesis:Occurs in Interphase IOccurs in Interphase
Cytokinesis:Occurs in Telophase I & Telophase IIOccurs in Telophase
Centromeres Split:The centromeres do not separate during anaphase I, but during anaphase IIThe centromeres split during Anaphase
Creates:Sex cells only: Female egg cells or Male sperm cellsMakes everything other than sex cells
Discovered by:Oscar HertwigWalther Flemming


Stands for:DeoxyriboNucleicAcidRiboNucleicAcid
Definition:A nucleic acid that contains the genetic instructions used in the development and functioning of all modern living organisms (scientists believe that RNA may have been the main genetic material in primitive life forms).
  • A single-stranded chain of alternating phosphate and ribose units with the bases Adenine, Guanine, Cytosine, and Uracil bonded to the ribose. 
  • RNA molecules are involved in protein synthesis and sometimes in the transmission of genetic information.
Function:Medium of long-term storage and transmission of genetic informationTransfer the genetic code needed for the creation of proteins from the nucleus to the ribosome.
Unique Features:The helix geometry of DNA is of B-Form. DNA is protected in the nucleus, as it is tightly packed. DNA can be damaged by exposure to ultra-violet rays.The helix geometry of RNA is of A-Form. RNA strands are continually made, broken down and reused. RNA is more resistant to damage by Ultra-violet rays.
Predominant Structure:Double- stranded molecule with a long chain of nucleotidesA single-stranded molecule in most of its biological roles and has a shorter chain of nucleotides
Bases & Sugars:Deoxyribose sugar; phosphate backbone; Four bases: adenine, guanine, cytosine and thymineRibose sugar; phosphate backbone. Four bases: adenine, guanine, cytosine, and uracil
Pairing of Bases:A-T(Adenine-Thymine), G-C(Guanine-Cytosine)A-U(Adenine-Uracil), G-C(Guanine-Cytosine)
Stability:Deoxyribose sugar in DNA is less reactive because of C-H bonds. Stable in alkaline conditions. DNA has smaller grooves, which makes it harder for enzymes to "attack" DNA.Ribose sugar is more reactive because of C-OH (hydroxyl) bonds. Not stable in alkaline conditions. RNA has larger grooves, which makes it easier to be attacked by enzymes.
Propagation:DNA is self-replicating.RNA is synthesized from DNA when needed.


Eukaryotic CellProkaryotic Cell
Number of chromosomes:More than oneOne--but not true chromosome: Plasmids
Cell Type:Usually multicellularUsually unicellular (some cyanobacteria may be multicellular)
True Membrane bound Nucleus:PresentAbsent
Example:Animals and PlantsBacteria and Archaea
Genetic Recombination:Meiosis and fusion of gametesPartial, undirectional transfers DNA
Lysosomes and peroxisomes:PresentAbsent
Microtubules:PresentAbsent or rare
Endoplasmic reticulum:PresentAbsent
Cytoskeleton:PresentMay be absent
DNA wrapping on proteins.:Eukaryotes wrap their DNA around proteins called histones.Multiple proteins act together to fold and condense prokaryotic DNA. Folded DNA is then organized into a variety of conformations that are supercoiled and wound around tetramers of the HU protein.
Golgi apparatus:PresentAbsent
Chloroplasts:Present (in plants)Absent; chlorophyll scattered in the cytoplasm
Flagella:Microscopic in size; membrane bound; usually arranged as nine doublets surrounding two singletsSubmicroscopic in size, composed of only one fiber
Permeability of Nuclear Membrane:Selectivenot present
Plasma membrane with steroid:YesUsually no
Cell wall:Only in plant cells and fungi (chemically simpler)Usually chemically complexed
Cell size:10-100um1-10um


Embryo:The dicotyledons embryo has two cotyledons.Monocotyledons have one cotyledon.
Leaf venation:Leaf veins are reticulated (branched).Leaf veins are parallel.
Flowers:Petals in multiples of four or five. May bear fruit ( if tree)multiples of three
Secondary growth:Often presentAbsent
Stem and vascular system:Bundles of vascular tissue arranged in a ring. The vascular system is divided into a cortex and stele.Bundles of vascular tissue scattered throughout the stem with no particular arrangement, and has no cortex.
Pollen:Pollen with three furrows or poresPollen with a single furrow or pore
Examples:Legumes (pea, beans, lentils, peanuts) daisies, mint, lettuce, tomato, oak, tree, etc.Grains, (wheat, corn, rice, millet) lilies, daffodils, sugarcane, banana, palm, ginger, onions, bamboo, sugar, cone, palm tree, banana tree,grass
Root Pattern:Taproot systemFibrous roots
Presence or absence of wood:both herbaceous and woodyherbaceous
# of seed leaves:2 seed leaves1 seed leaf

Regular FluSwine Flu
Strains:The strains that cause are Influenza virus A, B and C.The known strains that cause swine flu include subtypes of influenza A known as H1N1, H1N2, and H3N2.
Overview:Regular flu or influenza may be caused by RNA viruses belonging to the family Orthomxoviridae.Swine flu (also known as pig influenza, hog flu or pig flu) is caused by a family of viruses that is endemic to pigs.
Symptoms:Fever, chills, sore threat, body ache, headache, coughing, fatigue, nausea, vomiting and discomfort.Fever, chills, muscle pain, weakness, fatigue, sore throat, headache, and discomfort.
Prevention and Control:VaccinationVaccination
Treatment:Anti-viral drugs such as neuraminidase inhibitors and M2 protein inhibitors.Prescription drugs like Tamiflu or Relenza.

Definition:Antibiotics are small molecules or compounds that are effective in treating infections caused by organisms such as bacteria, fungi and protozoa.Vaccines are dead or inactivated organisms or compounds that are used to provide immunity to a particular infection or disease.
Source:Antibiotics can be derived from natural, semi-synthetic and synthetic sources.Sources of vaccines include live or inactivated microbes, toxins, antigens etc.
Types:Antibiotics are classified according to their structure and mechanism of action into 3 classes:
  • cyclic lipopeptides, 
  • oxazolidinones & 
  • glycylcyclines. 
The first 2 are targeted at Gram positive infections and the last one is a broad spectrum antibiotic
Vaccines are of different types-live and attenuated (vaccines against chicken pox), inactivated (BCG vaccine), subunit (Hepatitis C), toxoid, conjugate, DNA , recombinant vector vaccines and other experimental vaccines.
Side effects:Some antibiotics may have side effects like diarrhea, nausea and allergic reactions.Some vaccines may cause allergic reactions.

Saturated FatsUnsaturated Fats
Type of bonds:Consist of SINGLE bondConsist of  at least 1 DOUBLE bond
Recommended consumption:Not more than 10% of total calories per dayNot more than 30% of total calories per day
Health Effects:Excessive consumption is not good because of their association with atherosclerosis and heart diseases.Unsaturated fats are considered good to eat if you are watching your cholesterol. Also high in antioxidants.
Cholesterol:Saturated fats increase Low Density Lipoproteins (LDL or bad cholesterol) & Very Low Density Lipoproteins (VLDL's).Sources of bad cholesterol are foods rich in trans fatty acids, refined carbohydrates, such as white sugar, and flour.Unsaturated fats increase High-Density Lipoprotein (HDL or good cholesterol) and decrease Low Density Lipoproteins (LDL or bad cholesterol). Sources of HDL include onions and Omega-3 fatty acids like flax oil, fish, foods rich in fiber like grains.
Commonly found in:Butter, coconut oil, whole milk, meat, peanut, butter, margarine, cheese, vegetable oil, fried foods, & frozen dinnersAvocado, soybean oil, canola oil and olive oil, sunflower oil, fish oils walnuts, flax, & red meats
Shelf Life:These are long lasting and do not spoil quicklyThese spoil quickly
Melting Point:HighLow
Physical state at room temperature:Solid (Trans Fats & Saturated Fats)Liquid (Monounsaturated & Polyunsaturated Fats- Omega 3's & 9's)
Examples:Hydrogenated Oils, Butter, Processed MeatsOlive Oil, linoleic acid, alpha-linolenic acid


Vitamin B
  • Currently 3.1
Vitamin B
Vitamin C
  • Currently 3.17/5
Vitamin C
Introduction (from Wikipedia):The B vitamins are eight water-soluble vitamins that play important roles in cell metabolism. Historically, the B vitamins were once thought to be a single vitamin, referred to as vitamin B (much as people refer to vitamin C or vitamin D).Vitamin C or L-ascorbic acid is an essential nutrient for humans, in which it functions as a vitamin. Ascorbate (an ion of ascorbic acid) is required for a range of essential metabolic reactions in all animals and plants.
Classification:Compounds involved in cell metabolismAntioxidants
Types:Vitamins B1, B2, B3, B5,B6, B7, B9, B12Vitamin C (Ascorbic acid)
Source:Meats, potatoes, lentils, bananasFruits and vegetables
Diseases caused by deficiency:Beriberi, pellagra, anaemia, ariboflavinosis, dermatitisScurvy
Toxicity:Neurological damageIndigestion
Dietary requirement:Varies for each type60-95 mg

Gram-negative BacteriaGram-positive Bacteria
Gram reaction:Can be decolourized to accept counter stain (Safranin or Fuchsine); stain red or pink, they don't retain the Gram stain when washed with absolute alcohol and acetone.Retain crystal violet dye and stain dark violet or purple, they remain coloured blue or purple with gram stain when washed with absolute alcohol and water.
Peptidoglycan layer:Thin (single-layered)Thick (multilayered)
Teichoic acids:AbsentPresent in many
Periplasmic space:presentAbsent
Outer membrane:PresentAbsent
Lipopolysaccharide (LPS) content:HighVirtually none
Lipid and lipoprotein content:High (due to presence of outer membrane)Low (acid-fast bacteria have lipids linked to peptidoglycan)
Flagellar structure:4 rings in basal body2 rings in basal body
Toxins produced:Primarily EndotoxinsPrimarily Exotoxins
Resistance to physical disruption:HighLow
Inhibition by basic dyes:HighLow
Susceptibility to anionic detergents:HighLow
Resistance to sodium azide:HighLow
Resistance to drying:HighLow
Cell wall composition:The cell wall is 70-120 Armstrong thick two layered.The lipid content is 20-30% (High), whereas Murein content is 10-20% (Low).The cell wall is 100-120 Armstrong thick, single layered. The Lipid content of the cell wall is low , whereas Murein content is 70-80% (Higher).
Mesosome:Mesosome is less prominent.Mesosome is more prominent.
Antibiotic Resistance:More Resistant to antibiotics.More Susceptible to antibiotics

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