Exam 1: Cells & Organelles Flashcards
Cells are the ___ living unit
Smallest
How many cells does the body have?
35 trillion
Cells are typically _____.
Specialized; have specific tasks to perform
What does a group of cells that are like-minded create?
Tissues
Cells -> Tissues -> Organs -> Body
T/F Most cells do NOT replicate
False
If a cell cannot replicate, what will replicate for them in a different part of the body?
Progenitor cells
Ex: RBC cannot replicate; they are produced in the bone marrow
How much water is in the inside of cells and what is the compartment called?
70-85% of cells are water (by weight); the water is in the cytoplasm and that is where chemical reactions take place to form specialized tasks and keeps the cells alive
How do we keep things inside and outside of the cell?
Cell membrane/phospholipid bilayer; Hydrophilic/Charged heads and hydrophobic tails that are fatty
Hydrophobic = NO charge. Hydrophilic means = can have + or - charge
If something has a charge it can be dissolved in water. Remember that hydrophobic means not water dissolving.
What does the nucleus do?
The nucleus houses the cell’s DNA and protects it from viruses and bacteria with a double phospholipid bilayer membrane.
What allows things in and out of the nucleus?
Pores
Why do steroids need to get into the nucleus?
They affect transcription and need a way to turn on/off stress response proteins
What is the endoplasmic reticulum?
Extension of the nuclear wall
What does the smooth endoplasmic reticulum do?
Produces fats and lipids, stores things like calcium (specifically in the muscle cells)
Where does transcription occur?
In the nucleus
Where does translation occur?
Ribosomes
Where are proteins formed?
Rough ER; specifically the ribosomes
Where does lipid formation occur?
Smooth ER
What does the golgi apparatus do?
Post-translational processing; modifies proteins and folds them differently; gets rid of certain parts and throws them away
When proteins are active and ready to be used, how are they transported around the inside of cell?
Via transport vesicles
T/F Vesicles from the golgi are NOT modified.
False; Vesicles from the ROUGH ER are not modified while vesicles from the GOLGI are modified
How do cells transport things outside of the cell?
Via secretory vesicles; they will fuse within the cell wall and dump any contents needed outside of the cell
Describe the process of transcription/translation.
DNA is transcribed in the nucleus to become RNA. The RNA is allowed outside of the nucleus and makes contact with ribosomes in the cytoplasm to be TRANSLATED into proteins and linking amino acids together.
What percentage of RNA is translated in the rough ER?
95%
What percentage of RNA is translated in the cytosol?
5%
What are sugars used for?
Energy, help with structural function, and identification
What do cells use to move around?
Flagella
What small projections from the cell help move things surrounding the cell?
Cillia
What does the mitochondria do?
Produces ATP from energy compounds and O2
What is the job of the lysosome?
Lysosomes use the acidic internal environment to degrade things such as dysfunctional proteins
What is the role of peroxisomes?
Perioxisomes destroy things that need to be broken down and are better known for processing toxins within the cells; lots are found in the liver and they use oxidative stress to destroy things
What organelle(s) have 12-20 sets of our mother’s DNA?
Mitochondria
What organelle helps us in crime scenes?
Mitochondria
As you place more sugars on a protein what happens?
The less functional it will be.
