B1

• What are eukaryotic cells?

  Cells with a nucleus
• What size are eukaryotic cells?

  10-100 micrometers
• What are prokaryotic cells?

  Cells with no nucleus
• What size are prokaryotic cells?

  1-10 micrometers
• Where is the genetic material found in prokaryotic cells?

  Cytoplasm and in plasmids
• State the function of the nucleus

  Controls all activities of the cell, contains genetic information
• State the function of mitochondria

  Contains the enzymes for cellular respiration
• State the function of cell membrane

  Contains receptor molecules, selective barrier to control what enters cell
• State the function of cytoplasm

  Site of chemical reactions
• State the function of ribosomes

  Site of protein synthesis
• Name three subcellular structures a plant cell has that an animal cell does not

  Chloroplast, cell walll, vacuole
• State the function of chloroplasts

  Contain chlorophyll which absorbs light energy for photosynthesis to occur
• Where are chloroplasts found?

  Only in green parts of the plant
• What is the function of the cell wall?

  To protect and support the cell
• What is a plants cell wall made from?

  Cellulose
• State the function of the vacuole

  Contains cell sap which keeps the cell rigid and the plant upright
• What is the cell wall in a prokaryote made from?

  Peptidogylcan
• State the function of flagella

  Tail like structures that allow the cell to move through liquids
• State the function of pili

  Hairlike structures that allow the cell to attach to structures and transfer genetic material between bacteria
• State the function of a slime capsule

  Prevents dehydration of cell and protects it from poisonous substances. Also allows cell to stick to smooth surfaces
• State the function of plasmids

  Circular rings of DNA used to store extra genes
• State the advantages of a light microscope

  Cheap, portable, simple to prepare sample, natural colour of specimen seen, specimen can be alive
• State the advantage of an electron microscope

  Specimen can be viewed in higher resolution so subcellular structures can be seen
• State the disadvantages of an electron microscope

  Expensive, not portable, complex sample preparation, imagine in black and white, specimen must be dead
• Define resolution

  The smallest distance between two points that can be seen as separate entities
• Describe how to observe cells through a light microscope [6]

  Move the stage to its lowest position, select the objective lens with the lowest magnification, place slide with cells on it on the stage, raise stage to highest position, lower stage slowly using coarse focus knob until you see your image, turn fine focus knob slowly until object comes into clear focus.
• Why do scientists stain cells?

  To make the cells clearer or more visible
• What does DNA stand for?

  Deoxyribonucleic Acid
• Define chromosome

  A strand of DNA which contains genes
• How many chromosomes are in each human cell

  46
• Define genes

  Section of DNA which codes for a specific protein
• What is the DNA monomer called?

  Nucleotide
• What does a nucleotide consist of?

  Sugar, phosphate, base
• What are the complementary base pairs in DNA?

  A-T, C-G
• Rank the following in order from smallest to largest: nucleus, cell, gene, chromosome

  Gene, chromosome, nucleus, cell
• Describe the structure of DNA

  Two strands are joined together by complementary base pairs. Forms a double helix shape
• What is the purpose of transcription?

  To produce mRNA strand
• Describe the process of transcription

  DNA unzips, complementary base pairs pair up which forms an mRNA strand, mRNA strand leaves the nucleus, DNA zips back up
• What is the purpose of translation?

  To produce a protein from an mRNA strand
• Describe the process of translation

  mRNA strand attaches to ribosome, it is read in threes by tRNA, each triplet codes for a separate amino acid (triplet code), amino acids join together to form polymers, the chain of amino acids determines which protein will fold