Basic components of living systems Flashcards
What is the formula to calculate magnification?
size of image
magnification =
actual size of object
Why are cells stained before being viewed with a light microscope?
staining increases contrast between different cell components, makes them visible, and allows them to be identified
What is an eyepiece graticule?
a glass disc that fits on top of the eyepiece lens that is marked with a fine scale from 1 to 100
What is a stage micrometer?
a microscope slide with a very accurate scale in micrometers (µ) engraved on it
What is a scientific drawing
a labelled line drawing that is used to highlight particular features and does not include unnecessary detail or shading, it should always have a title and state the magnification
What is magnification?
how many times larger an image is than the actual size of the object being viewed
What is resolution?
the ability to see individual objects as separate entities
What is the function of the nucleus?
controls the metabolic activities of the cell as it contains genetic information in the form of DNA
What is the nucleolus?
area within the nucleus that is responsible for producing ribosomes
What is the function of mitochondria?
site of production of ATP in the final stages of cellular respiration
What are vesicles?
membranous sacs that are used to transport materials in the cell
What are lysosomes?
specialised forms of vesicles with hydrolytic enzymes that break down waste material in cells
What is the role of the cytoskeleton?
controls cell movement, movement of organelles within the cell, and provides mechanical strength to the cell
Name the three types of cytoskeletal filaments
microfilaments, microtubules, and intermediate fibres
Give two types of extension that protrude from some cells
flagella (whip-like protrusions) and cilia (tail-like protrusions)
