Chapter 4 - Cards 1-10: Cellular Landscape Flashcards
Get a lay of the cellular landscape.
The cell theory, originally composed in 1838, includes three primary tenets. Name them.
The cell is the basic unit of life.
All living things are composed of cells, whether one or many.
All cells arise from other cells.
Cells can be categorized into two broad groups. What are the names of these groups?
Prokaryotic (bacteria) and eukaryotic cells (plants and animals)
What main features characterize eukaryotic cells?
Eukaryotic cells have membrane-bound organelles (little organs) and linear DNA (don’t worry about the linear DNA part for now).
Suggestion: Expand the image and read all of the names of the organelles - you will need to know what each one does.
What main features characterize prokaryotic cells?
Prokaryotic cells lack membrane-bound organelles.
Suggestion: Read all the names of the parts of a Prokaryotic cell. Prokaryotes generally contain one circular chromosome within what is called the nucleoid region (unnecessarily fancy name). Prokaryotes can also possess circular plasmids outside the genome. Can you find the plasmid in this image? Can you guess what a plasmid does? Hint: R-plasmids provide the bacteria with antibiotic resistance. I predict antibiotic resistance is going to become one of the greatest problems in biology in the next decade.
FIll in this sentence:
If viruses are 1 inch long then bacteria (prokaryotes) are ___ inches long and animal cells (eukaryotes) are ___ inches long.
If viruses are 1 inch then bacteria (prokaryotes) are 10 inches and animal cells (eukaryotes) are 100 inches.
What is the difference between cytosol and cytoplasm?
The cytosol is all the stuff in a cell. The cytoplasm is all the stuff inside a cell except for the nucleus.
Potential quiz question: do prokaryotic cells contain a nucleus? Ans: No, they don’t contain organelles! This also explains why the cytosol and cytoplasm are the same things in prokaryotic cells.
Most eukaryotic cells are about 0.1 mm. Why don’t gigundous cells exist?
Surface AREA increases as a squared term (l•w). Volume increase as a cubed term (l•w•h). The cell membrane is unable to support too large a volume.
Explain the fluid mosaic model of the plasma (cell) membrane.
The fluid mosaic model is used to describe the plasma membrane. It is composed of lipids with a “mosaic” of embedded proteins and other components, and its “fluidity” allows these macromolecule components to move laterally within the membrane.
I hope that you see the beauty in this image (take the time to read each of the labels and think about the three billion or so years it took to create such an amazing structure).
Potential quiz question: Is the alpha helix composed of hydrophilic or hydrophobic residues (amino acids)?
In animal cells, which organelle serves as the location for DNA in the form of linear chromosomes?
The nucleus holds the cell’s chromosomes. It is also the site of DNA replication and transcription.
While the mitochondria also include DNA, mitochondrial DNA is found in small circular chromosomes, not linear ones.
I’ve attached a short explanation that I found to be very informative. Take a listen :)
Enlarge this diagram and explain the relationship between the nucleus and a gene (a section of DNA which codes for a protein).
The nucleus of a cell contains the DNA. The DNA is made up of genes. A gene provides instructions for making a protein
