Cell stucture Flashcards
What is the protoplasm?
It’s all the living parts of a cell
What is the largest cell and smallest smell in humans?
Largest - egg
Smallest - sperm
Why must cells be stained?
Organelles are colourless
What stain is used to see onion cells?
Iodine
What stain is used for cheek cells?
Methylene blue
What does the electron microscope do?
It shows the ultra structure of cells
What is the composition and function of the cell membrane?
Composition - phospho lipid bilayer and protein
Function - selectively permeable
What is the composition and function of the cytoplasm?
C - jelly-like fluid, mostly water
F - Chemical reactions
What is the composition and function of the nucleus?
C - nuclear membrane containing chromatin
F - controls all cells activities
What is chromatin made of
Protein and DNA
What is the function of nuclear pores?
Allow chemicals in and out of the nucleus
What is the function of the nucleolus
It makes ribosomes
What is the composition and function of the cell wall?
C - cellulose
F - provides strength + makes less flexible
What is the composition of the vacuole and it’s function?
C - cell sap [membrane]
F - stores water and salts also give strength and shape
Composition and function of chloroplasts
C - double membrane containing chlorophyll and DNA
F - photosynthesis
Composition and function of mitochondria
C - double membrane containing DNA
F - Respiration
Why are mitochondria plentiful in active cells?
A lot of energy is required and mitochondria release energy in respiration
Composition and function of ribosomes
C - RNA
F - protein synthesis
What is a cell sap made up of?
Sugar salts and water
Prepare slide for animal cell for examination
1) few drops of water on slide
2) using finger, rub mouth place on slide
3) dropper, add drops of methylene blue
4) mounted needle, lower coverslip
What was the purpose of the glass slide?
Allow light to pass through it
What was the purpose of the coverslip?
Holds the cells in place and stops it from drying out
How did you examine the cells under the microscope?
Lenses = magnify Wheels = focus Diaphragm = light
What was it difficult to see cells under low power
Cells are spread out and smaller