Lab Flashcards
(50 cards)
When should you use a compound microscope
When observing small, thin specimens that require high magnification, such as cells, bacteria, or thin tissue slices
When should you use a stereo microscope?
When observing larger, three-dimensional specimens such as whole insects, leaves, or small dissections that do not require high magnification.
What are the key differences between a compound and a stereo microscope?
A compound microscope provides high magnification (up to 1000x) and is used for thin specimens, while a stereo microscope provides lower magnification (10x-40x) and is used for viewing surface details of 3D objects
What part of the compound microscope controls the amount of light passing through the specimen?
The diaphragm (or iris diaphragm).
Why is it important to start with the lowest objective lens when using a compound microscope?
It provides the widest field of view, making it easier to locate and center the specimen before increasing magnification
What must all tissue plans and sketches include?
A title, a notes section, accurate proportions, and labels/annotations (at least two, preferably three).
What is the purpose of a tissue plan
A simplified drawing of a specimen, focusing on the arrangement and proportions of major structures rather than fine details
What is the difference between a tissue plan and a sketch
A tissue plan is a schematic representation of structures, while a sketch is a more detailed, realistic drawing
What is a good rule of thumb for making biological sketches
Use clear, unshaded lines, keep proportions accurate, and label major structures with straight lines
What are the essential components of a scientific data table
A descriptive title, labeled columns and rows, appropriate units, and clear data presentation
Why should tables be formatted neatly
Proper formatting ensures data is easy to read and interpret, reducing confusion during analysis
What is one of the most important safety rules in dissection
Always cut away from your body and handle sharp instruments carefully
Why is it important to pin down specimens during a dissection
It stabilizes the specimen, making it easier to observe and cut accurately
Why should you keep specimens moist during a dissection
Prevents tissues from drying out, which can make structures harder to identify and manipulate
What is leaf morphology
The study of leaf structure, including shape, venation, and arrangement
What are mesophytes
Plants adapted to moderate water conditions, like most deciduous trees
How do xerophytes reduce water loss
They have thick cuticles, sunken stomata, and reduced leaf surface area
What is a hydrophyte
A plant adapted to aquatic environments, often with large air spaces for buoyancy
Give an example of a leaf specialization
Spines in cacti reduce water loss and provide protection
What is transpiration
The loss of water from a plant through stomata
How does humidity affect transpiration
High humidity decreases transpiration because less water evaporates
How does wind affect transpiration
It increases transpiration by removing the boundary layer of humid air around the leaf
What is the function of stomata
They regulate gas exchange and water loss in plants
What is the function of vascular tissue
To transport water (xylem) and nutrients (phloem) throughout the plant
