A2.2 Cell structure

• Define the organism paramecium

  Paramecium is a eukaryotic organism living in freshwater environments it is classified as a heterotroph.
• how does paramecium conduct the life process nutrition

  paramecium is classified as a heterotroph and consumes smaller uni-cellular organisms for nutrition. the cytoplasm contains dissolved enzymes that catalyse metabolic reactions such as digestion and synthesis of cellular structures.
• how does paramecium conduct the life process movement


  they move through the beating of cilia
• how does paramecium conduct the life process of growth

  it grows until its at maximum surface area to volume ration, they then divide.
• How does paramecium conduct the life process of reproduction

  the nucleus divides via mitosis, to make another nuclei before the cell reproduces asexually, two paramecium fuses before dividing carrying out a form of sexual reproduction
• define the term 'naked' in prokaryotic DNA 


  the term 'naked' refers to DNA NOT being wrapped around histone proteins or is even associated with them.
• In context to the Golgi apparatus, sorting, concentrating and packing proteins into vesicles. Depending on the content, the vesicles are dispatched to 1 of 3. State the 3 


  within the cell, to organelles called lysosomes, the plasma membrane of the cell and section to the outside of the cell via exocytosis.
• define the organism Chlamydomonas

  chlamydomonas are eukaryotic organims that live in soil, freshwarer, oceans and even snow.
• outline and explain how chlamydomonas conduct the process of life nutrition

  chlamydomonas are classified as autotrophs and use photosynthesis as a means of nutrition.
• outline and explain how chlamydomonas conduct the process of life metabolism


  the cytoplasm and chloroplast contain dissolved enzymes that catalyse metabolic reactions such as digestion, photosynthesis, cellular respiration and the synthesis of cellular structures.
• outline and explain how chlamydomonas conduct the process of life movement 


  a light sensitive eyespot allows them to sense light and move using flagella.
• outline and explain how chlamydomonas conduct the process of life growth 


  they grow till the maximum surface area to volume ratio is met and then divide.
• Define Animalia 


  Animalia are holozoic, meaning they eat other organisms with internal digestion of nutrients.
• Define Fungi in relation to what saprotroph means 


  Fungi are saprotrophs, meaning they secrete digestive enzymes into their environment and then absorb nutrients into their body after there has been external digestion.
• State what vesicles are and distinguish the differences between transport vesicles and secretory vesicles.

  Vesicles are membrane bound sacs that contain and transport materials within cells. Transport vesicles move molecules between location inside the cell by budding off one organelle compartment and fusing with another. Secretory vesicles secrete molecules from the cell via exocytosis, and are also how new phospholipids are added to the cell membrane.
• state the 3 parts of cell theory

  The cell theory is a group of statements that serve as a tenet of life on earth. 1. all living things are composed of cells. 2. the cell is the basic unit of life. 3. cells come from pre-existing cells.
• Explain what endosymbiosis is, provide 2 examples of eukaryotic structures which evolved from endosymbiosis.

  Endosymbiosis is a term used to describe two organisms living together, with one inside the other. The endosymbiosis theory states that some organelles in eukaryotic cells were once prokaryotic microbes, resulting in the formation of the mitochondria and chloroplast.
• define lysosome in context to eukaryotic cells 


  small spherical organelles enclosed by a single membrane
• Compare and contrast cilia flagella 


  both are extensions from the cell surface which aid in cell movement, they are formed from modified centrioles called basal bodies. However, they differ in that cilia protrusions are short and numerous and beat in coordination, whereas flagella protrusions are longer and less numerous and move independently.
• Cell theory


  A group of statements that together serves as a tenet for life on earth
• Components of the cell theory

  • All living things are composed of living cells
  • The cell is the basic unit of life = meaning all living organisms consist of one or more cells
  • Cells come from pre-existing cells
• Cells are the basic structural unit of all living organisms, meaning that all living organisms consist of one or more cells
• Living things are composed of all cells
• Cell


  The basic unit of life, meaning it is the smallest structural unit that is capable of using energy to sustain itself in a highly ordered state
• Subcellular components have never been seen to perform the functions of life, whereas full cells have
• We have observed cells coming from other cells, but never observed spontaneous generation
• Deductive reasoning


  Based on a series of general observations, scientists deduce a single conclusion
• Inductive reasoning


  Based on specific observations and evidence, scientists notice a trend and induce a general rule
• Theory (in scientific use)

  A theory has been shown to be true through repeated observations and experiments. There is no current doubt. As of yet, no evidence has been collected that does not support the idea.
• Light microscope


  Most biologists use this microscope for investigating the structure of cells and tissue
• Electron microscope


  Electrons microscopes have higher magnification and resolution, but aren't practical for school use
• Magnification


  How much larger an object appears compared to its real size
• Determining total magnifying power of light microscope

  Multiply the magnifying power of the ocular by the magnifying power of the objective lens
• Wet mount


  A drop of water is used to suspend the specimen between the slide and cover slip
• Staining


  Chemicals that bind to structures within the sample and are used to make them show more clearly when being viewed
• Field of view


  The diameter of the area visible through microscope
• Estimating size of specimen in microscope field of view

  Estimate the fraction of the field of view that the specimen occupies, then multiply the FOV diameter by that estimated fraction
• Differences between light and electron microscopes

  • Magnification power
  • Resolution
  • Illumination Source
  • Advantages
  • Disadvantages
• There is consensus that life on Earth is composed of cells and that cells are the smallest unit of self-sustaining life
• Types of cells


  • Prokaryotic cells
  • Eukaryotic cells