Module 1 Cell as the Basis of Life

• Temperature, Concentration, pH are important factors in chemical reactions.
• Cells are the basic structural and functional units of organisms and all cells come from pre-existing cells.
• Cells can be classified into Prokaryotes (Unicellular Organisms) and Eukaryotes (Unicellular and Multicellular).
• Prokaryotes are more abundant and have a higher SA:V ratio than eukaryotes.
• Prokaryotes are divided into two groups: Archaea and Bacteria.
• Eukaryotes are more complex and large than prokaryotes, with an average size of 10-100um.
• Multicellular plants and animals are composed of a variety of different types of eukaryotic cells.
• Eukaryotes are divided into kingdoms: Amoeba, fungi, Plantae and animalia.
• Eukaryotes contain membrane bound organelles, each with a specific function within the cell.
• Organelles carry out all the biochemical processes and reactions like transpiration and photosynthesis.
• Endosymbiosis is the process where large prokaryotic cells engulfed smaller prokaryotic cells, resulting in the creation of photosynthesising chloroplasts and cells that used oxygen to produce their own energy, resulting in the creation of mitochondria.
• The size of mitochondria and chloroplasts tend to be the same size as bacteria.
• The way mitochondria and chloroplasts divide tends to be the same process as prokaryotes.
• Cytoplasm consists of a liquid based background, in which there are dissolved chemical substances such as ions like chloride ions.
• The nucleus is a large spherical oval structure in the cytoplasm, it is transparent and colourless, and has two main functions: storing the cell’s DNA and being responsible for the cell’s growth, reproduction etc.
• The nucleus produces ribosomes.
• Chloroplasts are only found in plant cells, photosynthesis occurs in this section of the cell, and the chloroplast uses the sunlight to convert the energy into sugars to power the plant cells.
• Inside of the chloroplasts there are little green chlorophylls (molecules).
• Vacuoles are sac-like structures that store materials such as water, ions, wastes and proteins, and their size depends on the shape and size of the cell.
• Carrier proteins can assist in facilitated diffusion or active transport (May require energy to go against the concentration gradient).
• A fluorescence microscope has better resolution than a light microscope.
• The cytoskeleton is present in all cells and is a complex network of interlinking filaments and tubules throughout the cytoplasm.
• An electron microscope has greater resolution due to shorter wavelengths.
• Plants only use their mitochondria at night.
• Receptor proteins cause the cells to respond only to signals from substances.
• A light source passes through a condenser lens then through the specimen.
• Some proteins penetrate the whole way through the membrane, forming channels that allow some materials to pass through the membrane.
• In a fluorescence microscope, the sample is labeled with a fluorescent dye that attaches to particular structures.
• Many cells were seen for the first time with the invention of the electron microscope.
• Cell size is measured in micrometres, where 1mm = 1000micrometres.
• Cells coordinate activities within their internal and external environments through movement across cell membrane, diffusion, and cell function.
• Mitochondria are responsible for creating more than 90% of the energy needed to sustain life.
• Animals have more mitochondria than plants.
• As temperature decreases, cell membranes with a high percentage of saturated fatty acid may solidify.
• In a fluorescence microscope, the sample is illuminated with a high intensity source of light that causes the fluorescent substance to emit light.
• Computer enhanced technology allows microscopic images to be digitally processed to allow cells to be viewed in different ways.
• Mitochondria produce the energy for the cell known as ATP through cellular respiration.
• The cytoskeleton supports, shapes and helps facilitate movement.
• The beam of light passes through the convex objective lens, the image is magnified and viewed through the ocular lens.
• The mitochondria is the powerhouse of the cell.