Sizes and maths Flashcards
What does 1cm equal to in m?
1x10⁻²m = 1cm
What does 1mm equal in m?
1x10⁻³m = 1mm
What does 1 micrometer equal in m?
1x10⁻⁶ = 1μm
What does 1 nanometre equal in m?
1x10⁻⁹ = 1nm
Order of scales
Metre
Centimetre
Millimetre
Micrometer
Nanometre
Order of magnitude
A tool used to compare the sizes of different things
1 order of magnitude larger means 10x larger
Object A is 1 order of magnitude larger than object B meaning
object A is 10x larger than Object B
Object A is 2 orders of magnitude larger than object B
Object A is 100x larger than B
Pattern of orders of magnitude
Every order is 10x greater
How can we easily find out how many orders of magnitude an object is bigger by?
Count the zeros
1 zero = 1 order of magnitude
2 zeroes = 2 orders of magnitude
Etc etc
Surface area : volume ratio meaning
The ratio of the surrounding area (the surface area) : the stuff inside
Larger surface area to volume ratio meaning
The object is small
And contains a large difference to the surrounding area to the big amount of space inside
Eg 12 : 1
Small surface to volume ratio meaning
The object is large
And contains a smaller difference between the surrounding area and the stuff inside as the amounts are closer together
What happens to surface area to volume ratio as organisms get larger?
The ratio falls
Eg the numbers are closer together like 1: 2
What problem is there for multicellular organisms with surface area to volume ratio?
The surface area isn’t large enough for the volume as the numbers are too close
So cells on the inside can’t get oxygen needed as the oxygen can’t diffuse that far (too far away from surface)
