Midterm Review Flashcards
(39 cards)
What kind of distortion happened with compound microscopes?
Image reversal
Left-right, top-bottom
Advantages of stereoscopic dissecting microscope
Observe think and large objects under high mag.
Observe in 3D
No image reversal
How to find Total magnification
Ocular (10x) x objective lens magnification
How to measure field diameter
Put ruler slide under microscope.
Find how many mm there are in the circle for objective 4x.
Then turn to 10x and do the same.
For 40x divide the number you got for 4x by 10
How do you measure true diameter?
Field diameter x linear fraction
Linear fraction: estimate the portion of the field that the specimen takes up.
How to measure scale of drawing
Drawing diameter /true diameter
Put x after number
How to prepare a wet mount
Add drop of culture onto microscope slide
Add clean cover slip at angle!!
Cross section:
Longitudinal section:
Median section:
Radial section:
Cut at right angles to the longitudinal axis
Cut parallel to longitudinal axis
Cut along the middle of an object
Cut made along a radius of a circular object
Prokaryotic cells
Absence of nucleus and membrane bound organelles
May have chloroplasts (Cyanobacteria)
Found in bacteria , blue-green algae
4 differences between plant and animal cells
- large central vacuole in plants
- ridged cell wall (plants)
- chloroplasts
- centrioles are in animal cells (can’t be seen under microscope)
Some rules for biological drawings
- arrange labels in a straight column on the right hand side of the drawing
- use straight continuous label lines
- if too many labels make second column on left
- no shading, crosshatching
- Below drawing has…. title(underline if scientific), manner in which slide was prepared(cross section, wet mount, total mag. , scale
Enzyme facts
Proteins Specific enzyme has specific substrate Don’t require substantial heat Don’t change equilibrium Don’t affect free energy Emerge unaltered
Spectrophotometer
Measures light absorbed by products
500nm mode 0-1 absorbance
For enzyme experiments how can you tell which experiment is experimental or control?
Experimental has both substrate and enzyme present
Should have highest absorbance rate
Competitive vs. Non competitive inhibition
Blocks substrate by attaching to active site of enzyme
(Can be reversed if concentration of substrate is raised)
Inhibitor binds to a non active site and changes nature of enzyme
Two things that can alter enzyme activity
Ph and temp (independent variable-we can change them)
Absorbance is dependent
DNA is made up of
Nucleotides- 5 carbon sugar (deoxyribose, nitrogenous bass, phosphate, hydrogen bonds
Double helix
Leading and lagging strand
Leading 5’-3’
Lagging 3’-5’
Dina replication occurs in what phase of cell division
S phase of interphase
Mitosis
Cytokinesis
The division of nuclear material, separation of duplicated chromosomes into daughter cells that are identical to parent.
Segregation of the cytoplasm into two daughter cells
Interphase
(Cell not dividing)(chromosomes refereed to as chromatin)
G1 phase: immediately after division, period of intense metabolic activity resulting in cell growth and new organelles.
S phase: DNA rep. Occurs; chromosomes replicate into sister chromosomes he,d by centromere.
G2 phase: short, Cell is metabolically preparing to divide
Prophase
Chromatin coils and condense Into visible chromosomes.
Nuclear membrane starts to break down and nucleolus disappears.
Spindle of microtubules form across cell.
Sister chromatids attached to spindle by kinetochores
Spindles extend to poles
Metaphase
Orientation of the chromosomes at the equator of the spindle
Anaphase
Division the centromeres to produce two separate, functional daughter cells each with own centromere.
Daughter chromosomes migrate to poles.
