Mitosis, Cell cycle, and Cancer
Name the four different stages of Mitosis, and what happens during each one of them :D
Prophase, Metaphase, Anaphase, Telophase (PMAT)
In prophase, the nucleolus disappears and chromosomes condense and become visible.
(In prometaphase, kinetochores appear at the centromeres and mitotic spindle microtubules attach to kinetochores. )
In metaphase, chromosomes are lined up and each sister chromatid is attached to a spindle fiber.
In anaphase, sister chromatids (now called chromosomes) are pulled toward opposite poles.
In telophase, chromosomes arrive at opposite poles, and nuclear envelope material surrounds each set of chromosomes.
Finally, in cytokenesis, the two daughter cells are separated.
Name 5 different organelles found in an animal, plant, or bacterial cell, and their functions.
cell membrane controls what enters and leaves the cell nucleus The control center of the cell. Regulates all activities within the cell.
ribosome makes proteins by connecting specific amino acids together
cytoplasm gel-like substance that cushions organelles nucleolus assembles ribosomes
Golgi Apparatus/Body stack of membranes in the cell that modifies, sorts, and packages proteins from the endoplasmic reticulum
Endoplasmic Reticulum (ER) The transportation system of the cell. It moves materials around the cell. An intracellular highway along which molecules can move from one part of the cell to another.
Vacuole Cell organelle that stores materials such as water, salts, proteins, and carbohydrates in plants. In animal cell stores waste. It is larger in the plant cell.
DNA A complex molecule containing the genetic information that makes up the chromosomes.
Microtubules Thick hollow tubes of protein that make up the cilia, flagella, and spindle fibers.
Mitochondria Powerhouse of the cell, organelle that is the site of ATP (energy) production.
cell wall A rigid layer of nonliving material that surrounds the cells of plants and some other organisms. Gives support to cell.
chloroplast An organelle found in plant and algae cells that captures sunlight to perform photosynthesis( making food for plant)
flagella A long, whip-like filament that helps some unicellular organisms move through water.
cilia short hair-like structures used to propel an organism through water. Also found in specialized cells such as the respiratory tract.
Rough Endoplasmic Reticulum A structure covered with ribosomes where many proteins for transport are assembled and move throughout the cell.
Smooth Endoplasmic Reticulum Membraneous structure in the cytoplasm that makes lipids.
Cytoskeleton network of protein filaments within some cells that helps the cell maintain its shape and is involved in many forms of cell movement
Lysosome cell organelle filled with enzymes needed to break down certain materials in the cell
Plasmid A small ring of DNA that carries accessory genes separate from those of the bacterial chromosome
Pili Appendages that allow bacteria to attach to each other and to transfer DNA
Capsule A sticky layer that surrounds the cell walls of some bacteria, protecting the cell surface and sometimes helping to glue the cell to surfaces.
Difference between active and passive transport.
Active transport uses energy, while passive transport does not.
my brain is burning this one is easy im sure she'll get it right so i wont type ;)
um im tired of writing questions just have free points (or ill come up with a question on the spot)
yay!
What is cancer? And how do malignant and benign tumor differ? How do the different types of tumors effect treatment plans for patients effected?
Cancer is the uncontrolled division of cells.
Malignant tumors are basically tumors that can metastasize, which is basically move to different parts of the body through metastasis (tumor growth bla bla bla), while benign tumors stay attached to the parent cancer cells...etc. etc.
TLDR: Malignant tumors move around, benign tumors stay put.
Mitochondria are observed in plant cells that contain chloroplasts. Why do you find mitochondria in photosynthetic tissue?
It's the fourth one.
Name three types of bulk transport :D
Endocytosis - plasma membrane (__bends/folds___) and (___engulfs__)the particle forming a vesicle
Phagocytosis - endocytosis of large molecules like food particles or bacteria
Pinocytosis - endocytosis of small molecules or liquids
Exocytosis - a membrane bound vesicle goes to the side of the cell, fuses with the cell membrane and expels its innards outwards (active transport to transport things to outside of the cell)
Describe two ways that decreasing temperature would affect the rate of diffusion of molecules across a cell’s plasma membrane.
A lower temperature means less energy in the molecules, so they will move at a slower speed. Lowering temperature also decreases the kinetic energy of the molecules in the plasma membrane, compressing them together. This increases the density of the plasma membrane, which slows diffusion into the cell.
different type of osmotic pressure and how they work and animal/plant cell responses
Osmotic Pressure:
Levels of osmotic pressure:
Hypertonic - Inside of the cell has a lower solute (more solvent) concentration than outside the cell. Water moves out of the cell.
Describe what happens to cell: The cell will quickly become dehydrated and will deflate as water rushes out of the cell to maintain a stable concentration gradient equilibrium. Called plasmolysis when the cell contracts/shrinks due to the movement of water molecules across the cell membrane.
Hypotonic Inside of the cell has a higher solute (more solvent) concentration than outside the cell. Water moves into the cell.
Describe what happens to cell: The cell will have a lot of water rush into the cell, because it isn’t being obstructed by other particles and has a higher concentration of water outside, which makes the cell enlarge and swell until it can pop (cytolysis).
How does cancer occur? (What causes cancer?)
Cancer can primarily occur due to mutations (accumulated sometimes) within the cell's DNA, causing things to malfunction and uncontrolled division to occur. Issues with genes like the p53 gene and other checkpoint genes can also cause cancer (also mutations). So, it's basically mutations :/
(explain frame shift if you want)
Compare and contrast the cell wall and the cell membrane.
CELL WALL
CELL MEMBRANE
Present only in plants and in some fungi, bacteria, algae. Present in all types of cells, in humans, animals, plants, bacteria, etc.
It is the outermost part of the plant cellIt is the outermost covering the animal cells
It is made up of pectin, chitin, lignin, glycoproteins, glycolipids, sugar, and cellulose.It is a lipid bilayer. And is composed of lipoproteins and carbohydrates.
The cell wall is 0.1 μm to several μm in thicknessThe cell membrane is 7.5–10 nm in thickness
It is the thick and rigid structure with a fixed shape.It is a thin and delicate structure. It is flexible to change the shape as needed.
It protects the cell from the external environment.It protects and maintains the internal environment of the cell.
The cell wall is metabolically inactiveThe cell membrane is metabolically active.
The cell wall grows in thickness over time. Further, it occupies the whole cell in the plant as the cell ages and dies.It is of the same thickness for the lifetime of the organism.
The cell wall is fully permeable to smaller molecules with the size of 30-60 kDa.The membrane is selectively permeable and controls the movement of the substance into and outside the cell.
Functions include protection from the external environment.Functions include permeability, signal reception, motility conduction, cell division, sexual reproduction, etc.
Both of the regular intravenous solutions administered in medicine, normal saline and lactated Ringer’s solution, are isotonic. Why is this important?
because if you use hypotonic or hypertonic then your cells will go boom or weew
whats an aquaporin
water protein channel
What is the direction of water flow for a bacterial cell living in a hypotonic environment? How do cell walls help bacteria living in such environments?
The water will go into the cell. Hypotonic environments have lower concentrations of solute outside compared to inside the cell, and osmosis will move water across the concentration gradient. Cell walls, like in plant cells, help bacteria maintain their structure and not burst. It protects the bacteria from osmotic shock and helps them withstand osmotic pressure.
Why do heart and brain cancer rarely occur?
Because your heart and brain cells (neurons) rarely if ever divide, there is very little room for mutations to occur. Therefore, it is more rare and difficult to find patients with such types of cancer.
Cancers usually occur more often in places with primarily epithelial cells, which divide often, allowing more space for mutations.
Why are membrane bound organelles desirable? Name three membrane bound organelles.
They can help separate cellular reactions within structures, isolating chemicals and enzymes from places they shouldn't be.
Some membrane bound organelles
A cell develops a mutation in its potassium channels that prevents the ions from leaving the cell. If the cell’s aquaporins are still active, what will happen to the cell? ( Be sure to describe the tonicity and osmolarity of the cell.) you can ignore that part if you want i dont think its gonna be tested :D
osmolarity -- the concentration of a solution expressed as the total number of solute particles per liter.
tonicity -- the capability of a solution to modify the volume of cells by altering their water content.
If the mutation occurs in the potassium channel, accumulation of the potassium ions occurs that is pumped into the cell due to this osmolarity increases inside the cell by creating the hypotonic solution.
As plasma membrane is selectively permeable to water so that water will flow into the cell by the aquaporins, If the concentration of potassium is high, then enough water will flow into the cell to lyse it.
How an extracellular solution develops changes in a cell volume by affecting the osmosis is described by the tonicity whereas the total solute concentration of the solution is described by the osmolarity.
explain how a sodium-potassium pump works
The sodium-potassium pump goes through cycles of shape changes to help maintain a negative membrane potential. In each cycle, three sodium ions exit the cell, while two potassium ions enter the cell. These ions travel against the concentration gradient, so this process requires ATP
uh visual explanation if diane wants it
Pathogenic E. coli have recently been shown to degrade tight junction proteins during infection. How would this provide an advantage to the bacteria?
The tight junction (TJ) constitutes the barrier both to the passage of ions and molecules through the paracellular pathway and to the movement of proteins and lipids between the apical and the basolateral domains of the plasma membrane.
Disruption of the tight junctions will allow paracellular transport of the bacteria, bacterial-derived lipopolysaccharides (LPS), and luminal bacteria. This can lead to LPS entering systemic circulation and causing disease.
Chemotherapy drugs such as vincristine (derived from Madagascar periwinkle plants) and colchicine (derived from autumn crocus plants) disrupt mitosis by binding to tubulin (the subunit of microtubules) and interfering with microtubule assembly and disassembly. Exactly what mitotic structure is targeted by these drugs and what effect would that have on cell division?
Chemotherapy drugs like vincristine and colchicine target the mitotic structure known as spindle fibers, which are formed with the help of tubulin. By binding to tubulin, these drugs disrupt microtubule assembly and disassembly, preventing the formation of spindle fibers and ultimately halting cell division.
There are folds within the inside of a mitochondria called cristae, and the inside where the reaction happens is called a 'matrix'. How does this help the mitochondria perform its function?
It helps increase the surface area of the inner folds, which helps it more efficiently convert glucose to ATP for energy! Extra points if you can name what ATP stands for :D
An organism is excreting ions in its urine. What is likely the current tonicity of the organism’s cells, and why?
Tonicity refers to the relative concentration of solutes in the fluid inside and outside of cells. Hypotonicity means a lower concentration of solutes outside the cell, causing water to enter the cell. Hypertonicity means a higher concentration of solutes outside the cell, causing water to leave the cell.
The organism is excreting ions in its urine. When ions are excreted, they are being removed from the body fluids, decreasing the overall solute concentration in the body fluids.
Removing ions (solutes) from the body fluids decreases the solute concentration in these fluids. This can make the external environment of the cells relatively less concentrated compared to the inside, resulting in hypotonicity.
Based on the analysis, the cells are likely to experience hypotonicity due to having less solute in the body fluids. Therefore, the correct answer is (d) hypotonicity due to less solute in its body fluids.
explain the fluid mosaic membrane
membrane = mosaic of components
fluid = liquid and easily bendable due to silly little phospholipids
The major role of the cell wall in bacteria is protecting the cell against changes in osmotic pressure, pressure caused by different solute concentrations in the environment. Bacterial cells swell, but do not burst, in low solute concentrations. What happens to bacterial cells if a compound that interferes with the synthesis of the cell wall is added to an environment with low solute concentrations?
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