Biology POB II Review Paper
POB II: Exam II Review
Chapter 6: tour of the cell
Microscopy:
• Microscopes provide a window to the cell.
• Most important tool in cytology
• Resolution has improved understanding of cells. o Resolving power – the smallest distance between two objects that allows them to be seen as distinct objects. o Resolving power of the human eye is 0.1 mm
• Light microscope – uses glass lenses and visible light to form a magnified image of an object. o Resolving power of about 100 nm (.0002 mm) o Advantage: View of cells and organelles o Disadvantage: Cannot visualize ribosomes o Types of light microscopy:
Brightfield microscopy- passes light directly through specimen. Very little contrast (will show natural colors).
Brightfield stained …show more content…
Function almost like separate small organisms
If the cell requires more energy they have more mitochondria.
Plastids
• Photosynthesize or store materials
• Found only in plants and certain protists.
• A familiar plastid is the chloroplast which contains the green pigment chlorophyll and is the site of photosynthesis
• Light is converted to energy of chemical bonds, provides food for the plant and for other organisms.
• Chloroplasts have a double membrane like mitochondria. o Chloroplasts contain membrane structures that look like stacks of pancakes – called grana. o The circular stacks that make up grana are called thylakoid.
A Single membrane sack made of phospholipids and proteins
Contain chlorophyll and carotenoids
Used to harvest lightenergy and convert it to glucosefrom CO2 and H2O o Fluid inside the chloroplast is the stroma and contains the grana, ribosomes, enzymes, DNA. o Not all plant cells have chloroplasts
• Other types of plastids include the chromoplasts and leucoplasts o Chromoplasts – may be important just for color ( tomato color from carotenoids) o Leucoplasts – are involved in storage of starch and
Chapter 6: tour of the cell
Microscopy:
• Microscopes provide a window to the cell.
• Most important tool in cytology
• Resolution has improved understanding of cells. o Resolving power – the smallest distance between two objects that allows them to be seen as distinct objects. o Resolving power of the human eye is 0.1 mm
• Light microscope – uses glass lenses and visible light to form a magnified image of an object. o Resolving power of about 100 nm (.0002 mm) o Advantage: View of cells and organelles o Disadvantage: Cannot visualize ribosomes o Types of light microscopy:
Brightfield microscopy- passes light directly through specimen. Very little contrast (will show natural colors).
Brightfield stained …show more content…
Function almost like separate small organisms
If the cell requires more energy they have more mitochondria.
Plastids
• Photosynthesize or store materials
• Found only in plants and certain protists.
• A familiar plastid is the chloroplast which contains the green pigment chlorophyll and is the site of photosynthesis
• Light is converted to energy of chemical bonds, provides food for the plant and for other organisms.
• Chloroplasts have a double membrane like mitochondria. o Chloroplasts contain membrane structures that look like stacks of pancakes – called grana. o The circular stacks that make up grana are called thylakoid.
A Single membrane sack made of phospholipids and proteins
Contain chlorophyll and carotenoids
Used to harvest lightenergy and convert it to glucosefrom CO2 and H2O o Fluid inside the chloroplast is the stroma and contains the grana, ribosomes, enzymes, DNA. o Not all plant cells have chloroplasts
• Other types of plastids include the chromoplasts and leucoplasts o Chromoplasts – may be important just for color ( tomato color from carotenoids) o Leucoplasts – are involved in storage of starch and