alevel biology

• What are the four types of microscopes mentioned?

  Light, transmission electron, scanning electron, laser scanning confocal
• Why do light microscopes have poor resolution?

  Due to the wavelength of light
• What type of samples can be used with light microscopes?

  Living samples
• How do transmission electron microscopes create images?

  Electrons pass through the specimen
• What type of image do scanning electron microscopes produce?

  3D images
• What do laser scanning confocal microscopes use to create images?

  Laser light
• What is resolution in microscopy?

  Minimum distance to view objects separately
• How is resolution determined in light microscopes?

  By the wavelength of light
• How is resolution determined in electron microscopes?

  By the wavelength of electrons
• What does magnification refer to?

  How many times larger the image is
• What are the four types of slide preparation?

  Dry mount, wet mount, squash slide, smear slide
• What is a dry mount slide?

  Specimen placed on a slide with a cover slip
• What is a wet mount slide?

  Specimen added to water or stain before covering
• What is a squash slide?

  A wet mount with a pressed cover slip
• What is a smear slide?

  Sample smeared across the slide
• What is the eyepiece graticule used for?

  To measure the size of objects viewed
• How do you calibrate the eyepiece graticule?

  Using a stage micrometer
• What is the formula for magnification?

  Size of image / size of real object
• How do you convert millimeters to micrometers?

  Multiply by 1,000
• What is differential staining?

  Using multiple stains for cell components
• What are two common stains used in microscopy?

  Crystal violet and methylene blue
• What is the purpose of scientific drawings?

  To accurately represent observed structures
• What are the rules for creating scientific drawings?

  Use pencil, title, state magnification, label features
• What is the function of the cytoskeleton?

  Provides mechanical strength and shape
• What are the two types of endoplasmic reticulum?

  Rough and smooth endoplasmic reticulum
• What is the function of rough endoplasmic reticulum?

  Protein synthesis for secretion
• What is the function of smooth endoplasmic reticulum?

  Lipid and carbohydrate synthesis
• What is the Golgi apparatus responsible for?

  Modification and transport of proteins
• What are lysosomes?

  Vesicles containing digestive enzymes
• What is the function of mitochondria?

  Site of aerobic respiration and ATP production
• What type of ribosomes are found in eukaryotic cells?

  80S ribosomes
• What type of ribosomes are found in prokaryotic cells?

  70S ribosomes
• What is the structure of ribosomes?

  Two subunits of protein and RNA
• What is the role of the nucleus?

  Site of DNA replication and transcription
• What is the function of the nucleolus?

  Site of RNA production and ribosome synthesis
• What are chromosomes made of?

  Protein-bound DNA wrapped around histones
• What is the function of cilia?

  Move substances or act as sensory organs
• What is the function of flagella?

  Provide mobility to certain cells
• What are microtubules involved in?

  Spindle fiber formation during cell division
• What is the role of the cytoplasm?

  Site for cellular processes and organelle suspension