The Cell - Chapter 5 Flashcards
What are the three ideas of cell theory? Who created them?
- All living things are composed of one or more cells. 2. Cells are organisms’ basic units of structure and function. 3. Cells come only from preexisting cells. Matthias Schleiden, Theodor Shwann and Rudolph Virchow
What are the three major parts of a cell?
outer boundary, interior substances, control region
Describe the outer boundary.
is the plasma or the cell membrane, acts as a barrier protecting the inside, acts as food/gas/waste exchange
Describe the interior substances.
the cytoplasm and organelles
What is the cytoplasm?
the watery fluid that fills the cell and surrounds the organelles. It is always moving, which is called cytoplasmic streaming
What are organelles?
What is the nucleus?
**The control centre of the cell. **It sends instructions to organelles to perform specific functions. It is surrounded by a nuclear membrane (which has holes called nuclar pores) and it contains DNA, RNA or BOTH (genetic material), and a nucleolus.
What is the nucleoplasm?
A thick watery fluid (same as cytoplasm) contained in the nucleus.
What is the nucleolus?
A spherical organelle in the nucleus that synthesizes and assembles ribosomal RNA.
What are the two basic types of cells?
prokaryotic and eukaryotic
What are prokaryotic cells?
What are eukaryotic cells?
They have a nucleus and membrane bound organelles. They are bigger than prokaryotes.
What does a cell do when it reaches its maximum size?
It divides by mitosis because its surface area (cell membrane) is too small to fit its volume (inside).
What is the plasma or cell membrane composed of?
fat (lipids) and proteins. Makes phospholipid bilayer.
What is another name for the phospholipid bilayer and what are its two parts?
also called fluid mosaic model. Has the hydrophilic layer and pydrophobic layer.
