Chapter 4 Flashcards
Type of microscope that uses visible light passed through a specimen, and then through a glass lenses. The lenses bend the light in such a way that the image of the specimen is magnifies as it is project into your eye or camera
- Light microscope (LM)
The theory that states that all living things are composed of cells and that all cells come from other cells.
Cell theory
Electron microscope (EM)
Type of instrument that focuses a beam of electrons through a specimen or onto its surface
The two main components of a cell’s plasma membrane
- A head with a negatively charged phosphate group. Hydrophilic (water-loving) heads face outward, exposed to the aqueous solutoins on both sides of a membrane.
- Two nonpolar fatty acid tails. Hydrophobic tails point inward, mingling together and shielded from water.
- The two phospholipids form a two-layer sheet called a phospholipid bilayer
The most obvious difference between a prokaryotic and eukaryotic cell.
Eukaryotic cell contains various organelles (‘little organs’) that perorm specific functions in the cell
Four basic function groups of eukaryotic cells
1)
Nucleus and ribosomes carry out the genetic control of the cell
2)
Organelles involved in the manufacture, distribution, and breakdown of molecules include the endoplasmic reticulum, Golgi apparatus, lysosomes, vacuoles, and peroxisomes.
3)
Mitochondria in all cells and chloroplasts in plant cells function in energy processing.
4)
Cytoskeleton, plasma membrane, and plant cell walls all provide structural support, movement, and communication between cells
The ____ contains most of the cell’s DNA and controls the cell’s activities by directing protein synthesis.
nucleus
The ____ encloses the nucelus in a double membrane. Uses protein-lined pores to controls the flow of materials into and out of the nucleus.
nuclear envelope
The structure in the nucleus where rRNA (ribosomal RNA) is synthesized.
nucleolus
What are the main functions of the nucleus.?
- To house and copy DNA and pass it on to daughter cells in cell division.
- To build ribosomal subunits
- To transcribe DNA instructions into RNA and thereby control the cell’s functions
The cellular components that use instructions sent from the nucleus to carry out protein synthesis.
Ribosomes
What role do ribosomes play in carrying out the genetic instructions of a cell?
- Ribosomes synthesize proteins according to the instructions carried by messenger RNA from the DNA in the nucleus.
The endomembrane system includes:
- Nuclear envelop
- Endoplasmic reticulum
- Golgi apparatus
- Lysosomes
- Vacuoles
- Plasma membrane
Why is smooth endoplasmic reticulum called ‘smooth?’
- It lacks attatched ribosomes
Why is rough endoplasmic reticulum called ‘rough?’
- It has ribosomes that stud the outer surface
Enzymed of the ____ ER are important in the synthesis of lipids, including oils, phospholipids, and steroid.
smooth
One of the functions of the ____ is to make more membrane. Phospholipids made by enzymes of the ___ are inserted into the ER membrane (thus the membrane grows).
Rough ER
Explain why we say that the endoplasmic reticulum is a
bio-synthetic factory.
The ER produces a huge variety of molecules, including phospholipids for cell membranes, steroid hormones, and proteins (synthesized by bound
ribosomes) for membranes, other organelles, and secretion by the cell.
