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