Cell Biology

Biology

Cells – topic one

Structure of different cells

Animal

• nucleus
• cytoplasm
• mitochondria 
• ribosomes
• cell membrane

Plant

• Nucleus
• cytoplasm
• chloroplast
• cell membrane
• vacuole
• cell wall
• ribosomes
• mitochondria

Microscope and magnification

Magnification – the act or process of enlarging an image of a physical object    

Resolution – The shortest distance between two points in a specimen that can still be distinguished by the observer

Laser imaging -  laser imaging combines high-resolution optical images with depth salacity which allows us to view tiny structures.

Why are microscopes useful?

• Helps us see microorganisms and discover new microscopic species
• Can be used to make medicine
• To investigate cell structure

Calculations for magnifying

I = Actual x Magnification

A = Image / magnification

M = Image / actual

Properties of different microscopes.

Light microscopes

• light 
• 2000x
• colour
• cheap, easy to use, detailed
• 2D

Electron microscopes

• Electron
• 2,000,000x 
• Black and white
• very informative, very accurate, very detailed 3D or 2D
• Expensive, hard to operate

Exam practical

Using a light microscope to identify a cheek cell.

By preparing a slide from a swab of cheek cells.

Then looking through a microscope at

Mitosis and meiosis

• Diploids – 46 chromosomes
• Haploids – 32
• 2 haploids = diploid
• Gametes – Sex cells
• Cytokinesis – the process of separating the cells.

Mitosis

• The parent the cell has reached its full size and is ready…