4.2 Prokaryotic Cells

4.2 Prokaryotic Cells

  • Important contributions were made to the theory by the man.
  • In this test, a doctor takes a small sample of cells from the patient's uterus and sends it to a medical lab to be stained and examined for any changes that could indicate cancer or a bug.
  • A cytotechnologist is a professional who studies cells via laboratory tests.
    • They are trained to determine which cellular changes are normal and which are abnormal.
    • Their focus is not limited to one area.
    • They study cells from all organs.
    • They consult a medical doctor when they notice a problem with their body tissue and fluids.
  • People's lives are saved by the work of tyotechnologists.
    • The chances of a successful outcome increase when a patient's treatment begins sooner.
  • The cells are from a Pap smear.
    • There are normal cells on the left.
    • The cells on the right have the human papillomaviruses.
    • The cells are larger.
    • Two of the cells have two nuclei instead of the normal number.
  • You can do the following by the end of this section: Name examples of prokaryotic and eukaryotic organisms, compare and contrast prokaryotic and eukaryotic cells, and describe the relative sizes of different cells.
    • The mostly single-celled organismsbacteria and Archaea are prokaryotes.
    • Eukaryotes include animal cells, plants, fungi, and protists.
  • All cells have the same four components: 1) a plasma membrane, an outer covering that separates the cell's interior from its surrounding environment; 2) a cytoplasm, which is the cell's genetic material; and 3) DNA, the cell's genetic material.
    • Prokaryotes and cells differ in several ways.
  • This is different in the eukaryotes.
  • The structure of a prokaryotic cell is shown in this figure.
    • All prokaryotes have a nucleus, ribosomes, and a cell wall.
    • Some of the structures are present in some of thebacteria.
  • The peptidoglycan cell wall and polysaccharide capsule are found in most prokaryotes.
    • The cell wall helps the cell maintain its shape and prevents dehydration.
    • The cell can attach to surfaces in its environment with the help of the capsule.
    • flagella, pili, and fimbriae are some of the prokaryotes that have flagella.
    • The flagella are used for walking.
    • The fimbriae attach to the cell.
  • The best way to prevent the spread of illnesses is to wash your hands.
  • Microbial are ubiquitous because they can only be seen with microscopes.
    • They live on many surfaces.
    • If someone sneezes into his hand and you touch the same door, the germs from the sneezer's mucus will be on your hands.
    • Microbes can enter your body if you touch your hands to your mouth, nose, or eyes.
  • Most of the microbes are beneficial.
    • Beer and wine can be made with the help of the microbes in your gut.
  • Scientists who study microbes are called microbiologists.
    • There are a number of careers for microbiologists.
    • They work in the food industry, as well as in the veterinary and medical fields.
    • They can work in the pharmaceutical sector by identifying new antibiotic sources that can treat infections.
  • Environmental microbiologists may look for new ways to use specially selected or genetically engineered microbes to remove pollutants from soil, as well as hazardous elements from contaminated sites.
    • We call them bioremediation technologies.
    • Microbiologists can provide insight and knowledge for designing, developing, and specificity of computer models ofbacterial epidemics.
  • Prokaryotic cells are smaller than eukaryotic cells, which have diameters ranging from 10 to 100mm.
    • The small size of the prokaryotes allows them to quickly diffuse to other parts of the cell.
    • Any waste produced in a prokaryotic cell can quickly diffuse.
    • This is not the case in eukaryotic cells, which have adapted to enhance transport.
  • Each unit of increase in a logarithmic scale represents a 10-fold increase in the quantity measured.
  • Small size is necessary for all cells.
    • We will look at the area and volume of a cell.
    • Not all cells are spherical in shape.
    • The formula for the surface area of a sphere is 4pr2, while the formula for its volume is 4pr3/3.
    • As the square of the cell's radius increases, its surface area increases, but its volume decreases.
    • As a cell increases in size, its surface area-tovolume ratio decreases.
    • If the cell had a cube shape, this principle would apply.
    • If the cell grows too large, there will not be enough surface area to support the increased volume.
    • As a cell grows, it becomes less efficient.
    • One way to become more efficient is to divide.
    • Other ways to increase surface area include folding the cell membrane, becoming flat or thin, and developing organelles that perform specific tasks.
    • These changes lead to the development of more sophisticated cells.
  • The surface area-to-volume ratio is affected by the cell's size.
    • A cell will divide or die if there is not enough surface area to support it.
    • The cell on the left has a volume of 1mm3 and a surface area of 6mm2, whereas the cell on the right has a volume of 8mm3 and a surface area of 24mm2.
  • eukaryotic cells are larger than prokaryotic cells.