Lecture - Chapter 6
Terms in this set (41)
What are the three important considerations of microscopy?
Magnification, resolution, and contrast
What is Magnification?
The ratio of an object's image size to its real size
What is Resolution?
The measure of the clarity of the image, or the minimum distance of two distinguishable points
What is Contrast?
Visible differences in brightness between parts of the sample
What is the Cell Theory?
All living things are composed of one or more cells, the cell is the basic unit of life, and all cells come from pre-existing cells
What are the basic features of all cells?
Cell membrane, cytoplasm, DNA or Genome, ribosomes
How does the Prokaryotic Domain differ than the Eukaryotic Domain?
Has a nucleoid (naked DNA) in the cytoplasm surrounded by cell membrane. Lacks a nucleus. Ribosomes are smaller than Eukaryote ribsomes
What is the plasma membrane?
Separation of inside and outside
What are tight junctions?
Preventage of leakage between cells. (Examples: Urinary Bladder, Digestive System)
What is desmosome?
Hold cells together like skin or heart cells
What are gap/communicating junctions?
Holes between cells that allow quick communication and exchange of ions or small molecules. (Example: Cardiac Muscle or Electric Eel)
What is Cytosol?
The liquid portion of a cell
What are Eukaryotic Cells?
Membrane bounded organelles. Especially nucleus (DNA)
Cytoplasm in region between the plasma membrane and nucleus
What are in animal cells and not plant cells?
Lysosomes - digestive enzymes. Centrioles - Help make cilia and flagella.Cilia and flagella.
What are in plant cells and not animal cells?
Chloroplast -Photosynthesis. Cell Wall - rigid and supports plant. Central Vacuole - Fills with water and creates turgor pressure
What makes up the nucleus?
Chromatin, nuclear membrane, nucleolus, and nuclear pore
What are chromatins?
Relaxed chromosomes (protein + dna)
What is the nuclear membrane?
Surrounds the nucleus
What is the necleolus?
Where ribosomes are assembled
What are nuclear pores?
Holes large enough for ribosomes to pass through
What determines the sequence of amino acids in a polypeptide?
Information from DNA goes to mRNA
What does DNA store?
Information to make proteins
What do Chromatins do?
Condense to form chromosomes for cell division
What is the nuclear envelope?
A double membrane of two phospholipid bilayers
What do Ribosomes do?
What are free ribosomes?
Make proteins in the cytoplasm
What are attached ribosomes?
Attached to RER and make proteins for endomembrane system
What makes up the endomembrane system?
SER, RER, Golgi Apparatus, Lysosomes, Cell or Plasma Membrane
What is SER?
Lacks the ribosomes of RER, produces lipids including steroids, detoxifies drugs, and stores calcium
What is RER?
Makes proteins for RER, Glogi, Lysosomes, and membrane
What do SER and RER do?
Produce new cell membrane
Concentrates/sorts and modifies proteins from RER to go to Lysosomes and Cell Membrane
What are Lysosomes?
Contains digestive enzymes with a pH of 5
What is phagocytosis?
Digestion of bacteria by white blood cells
What is autodigestion?
Self destructive mechanism
What is autophagy?
Digestion of damaged organelles
What is the mitochondria?
Site of cellular respiration: energy in food molecules are used to make ATP
What is the chloroplast?
Membrane called plastids
What is the endosymbotic theory?
Origin of mitochondria and chloroplasts. Formerly living prokaryotes living within larger eukaryotic cells
What evidence supports the endosymbiotic theory?
Both mitochondria have DNA more similar to aerobic bacteria and chloroplasts have DNA more similar to photosynthetic bacteria than to eukaryotic DNA
What do both mitochondria and chloroplast have?