Chapter 3 (Basic Cell Biology) Flashcards
What causes rough ER to have a rough appearance?
Rough ER is covered with ribosomes.
Which of the following organelles is composed of a series of flattened membrane sacs? Nucleus, Golgi Apparatus, Cytoskeleton, Peroxisome
Golgi Apparatus
Which of the following statements MOST accurately describes passive transport?
Passive transport allows molecules to scatter
Which of the following MOST accurately describes simple diffusion?
A NONPOLAR molecule passes through a CHANNEL
What would happen to a human cell that is placed in a 0.09% NaCl solution?
The cell would swell and burst
What portion of the plasma membrane is nonpolar? (has no charge)
The interior (fatty acids) is nonpolar.
What type of cell connection uses cadherins to tie neighboring cells to one another?
Desmosome
Where is interstitial fluid located?
It is between neighboring cells
Which of the following statements MOST accurately describes the nucleus?
The nucleus is the information center of the cell.
T or F: The cytoplasm includes the nucleus
FALSE: The cytoplasm includes everything surrounding the nucleus including smaller organelles, but does NOT include the nucleus itself.
Please describe the basic makeup of the cell membrane in one sentence.
The cell membrane is made of a phospholipid bilayer with a nonpolar interior of fatty acids and a polar exterior of phosphates (with glycerol between).
What is the job of the cell membrane?
It is the boundary that separates the living cell from non living surroundings and controls the intake or rejection of outside materials.
What is the difference between hydrophilic and hydrophobic? Which is polar?
Hydrophilic will mix with water and is POLAR. Hydrophobic does not mix well with water (greasy/fatty/etc) and is NONPOLAR.
How thick is the plasma membrane bilayer?
The bilayer is about 9 nm thick
Does the bilayer contain anything besides phosphate, glycerol, and fatty acids?
Yes, it contains cholesterol, glycolipids, glycoproteins, proteins, and enzymes, proteins and sugar groups for cell recognition (such as blood type, immune response, etc.)
T or F: The human plasma membrane contains cholesterol
TRUE: It keeps us fluid but strong.
T or F: Almost all human cells are uninucleate
TRUE. A few types of cells can be multinucleate (very hard working cells like hepatocytes and cardiomyocytes), and only one is anucleate (erythrocytes).
What multinucleate human cells might you find and why?
Cardiomyocytes and hepatocytes. The heart and liver are very hard working and may have mutiple nuclei to support their jobs.
What human cell is anucleate?
Erythrocytes
What is the shell surrounding the nucleus called?
The nuclear envelope
What parts are contained within the nucleus?
DNA in the form of chromatin, and the nucleolus which produces RNA to create new ribosomes in the cytosol outside the nucleus.
What does the nucleolus look like?
A dark spot within the nucleus
What average size is the human nucleus? Can it be seen with a light microscope?
It is approximately 5 microns across. Yes, it can be seen with a light microscope.
What are the parts of the cytoplasm?
The cytoplasm is everything within the cell excluding the nucleus and cell membrane. It contains the cytosol (80% water, fluid), organelles, and inclusions.
Is cytosol watery, or viscous in texture?
It’s viscous due to the amount of solutes in the water
Is cytosol purely water?
No, it contains dissolved solutes like enzymes, nutrients, and vitamins.
What is an inclusion?
A large chunk of a substance valuable to the cell, but too large to be broken down.
What type of inclusions might you find in a human cell?
Lipids (lipid drop), Melanin, Glycogen
What does ‘organelle’ mean?
Little Organ
Which organelle is NOT surrounded by a phospholipid bilayer?
Ribosomes
What size are ribosomes? What size are the parts and their names?
The entire ribosome is about 80s in size. The large subunit is ____ and the small subunit is 40s in size.
T or F: A busy cell can contain thousands of ribosomes.
True!
T or F: A ribosome’s job is to produce new proteins
True!
How does the mitochondria create ATP?
By oxidizing organic compounds
T or F: A busy cell will have only one mitochondrion
False: A busy cell may have more mitochondria. Ranges from tens to hundreds.
How many mitochondria might you expect to find in a human cell?
Tens to hundreds
What do mitochondria produce?
ATP (Adenosine Triphosphate), energy currency of the cell.
What is the structure of the endoplasmic reticulum?
An extensive network of flattened membrane sacs.
What does reticulum mean?
“Little net” in latin, or a network (MW dictionary)
T or F: The ER can fill over half the cell
True!
What are the two parts of the endoplasmic reticulum?
The rough ER (more of this) and the smooth ER (less of this).
What is the job of the Rough ER?
It excretes proteins into the extracellular space.
What is each sac within the golgi apparatus called BEFORE it pinches off?
A cistern
What is the small transport vehicle produced by the golgi apparatus called?
A vesicle
What is the function of the golgi apparatus?
Like a post office in the cell, directs things where to go and packages them for delivery
T or F: Lysosomes and vesicles are the same size
False: Lysosomes are LARGER than a vesicle
What do lysosomes contain and why?
Lysosomes contain enzymes and acids used to break down things within the cell (like a garbage can/recycling center)
What is a peroxisome?
A large, spherical organelle that contains protective enzymes that break down abnormal O2 in your body and detoxify free radicals.
What enzymes do a peroxisome contain?
Catalases and Oxidases (Cata=break down)
What is the cytoskeleton?
The network of long, thin protein fibers that support the cell.
What are the 3 types of cytoskeletal PROTEINS?
Microfilaments (Actin), Intermediate Filaments (Keratin [strongest]), and Microtubules (large fat tubes of Tubulin)
What is the basic description of diffusion?
All molecules in the universe contain kinetic energy; this causes molecules to scatter and spread out of their own accord
T or F: Passive transport can use ATP
False, passive transport methods do not use ATP.
Why can water move through the cell membrane easily, while other polar molecules cannot?
Water molecules are so tiny, they pass through like through a beaded curtain
What is Osmosis?
The passive transport of water.
What is the difference between hypertonic, hypotonic, and isotonic?
Hypertonic is a HIGH concentration of solutes outside the cell, hypotonic is a LOWER concentration outside the cell, and Isotonic is a balance of solutes within and without.
