Italics Topics are Triple Science ONLY
, Chapter 1 – Microscopes
Light Microscopes Electron Microscopes
- Uses beams of light - Uses beams of electrons Lens closest to your
- Small size - Large & non-portable eyes: 10x magnification
- Relatively cheap - Expensive
- Lower magnification - Higher magnification
- Not much training - Lots of training needed
Microscopes Keyword Definitions make image
3 different lens
- Specimen – object or organism that is being viewed clearer
- Magnification – number of times bigger the image is
- Resolution – the ability to distinguish between two where you put
- separate points on the image and it is the resolving the slide, it has
clips to hold it
- power of a microscope that affects amount of detail very sharp &
clear image
Magnification
Millimetre (mm)
÷1000 x1000
Size of image Micrometre (μm)
Size of real object ÷1000 x1000
Nanometre (nm)
projects light onto the slide, can be mirror or light bulb.
,Chapter 1 – Animal & Plant Cells
Sub-cellular Structures
Nucleus – controls all the activity of the cell and stores genetic
material.
Mitochondria – respiration occurs here, releasing energy.
Chloroplasts – contain chlorophyll and absorbs light for photosynthesis.
Ribosomes – proteins are synthesised (made) here.
Cytoplasm – a liquid gel where chemical reactions take place.
Cell Wall – made of cellulose, strengthens the cell.
Vacuole – it is full of cell sap which is full of ions which gives it salty
liquid. This keeps the plant fat and turgid.
Cell membrane = controls the movement of substances in and out.
Comparison
Plant cells have vacuoles, chloroplasts & cell walls, whereas animal
cells don’t have these sub-cellular structures.
Plant cells are bigger than animal cells in size.
Plant cells make their own food by photosynthesis, but animal don’t.
, Chapter 1 – Eukaryotes and Prokaryotes
Eukaryotes
- Animal cells and plant cells are Eukaryotes. All animals and including humans, plants, fungi and protista are
- Eukaryotes.
- All Eukaryotic cells have a cell membrane, cytoplasm, and genetic material enclosed in a nucleus.
Prokaryotes Comparison
- Example: Bacteria - Prokaryotes are older and simpler
- In prokaryotic cells, genetic material isn’t enclosed in nucleus. - Prokaryotes are simple and smaller therefore
- The bacterial chromosome is found as a single loop, and may - they can reproduce faster
- have extra small rings of DNA called plasmids, coding for - Eukaryotes have a nucleus, and membrane
- certain features like antibiotic resistance. - bound organelles
- Both have DNA, ribosomes, cytoplasm, and
- cell membranes
- Eukaryotes are larger and more complex
- Prokaryotes are single celled
- Eukaryotes can be multi-cellular
- Prokaryotes have single chromosomes
- (plasmid)
- Eukaryotes have multiple chromosomes
- (DNA in the nucleus)
, Chapter 1 – Microscopes
Light Microscopes Electron Microscopes
- Uses beams of light - Uses beams of electrons Lens closest to your
- Small size - Large & non-portable eyes: 10x magnification
- Relatively cheap - Expensive
- Lower magnification - Higher magnification
- Not much training - Lots of training needed
Microscopes Keyword Definitions make image
3 different lens
- Specimen – object or organism that is being viewed clearer
- Magnification – number of times bigger the image is
- Resolution – the ability to distinguish between two where you put
- separate points on the image and it is the resolving the slide, it has
clips to hold it
- power of a microscope that affects amount of detail very sharp &
clear image
Magnification
Millimetre (mm)
÷1000 x1000
Size of image Micrometre (μm)
Size of real object ÷1000 x1000
Nanometre (nm)
projects light onto the slide, can be mirror or light bulb.
,Chapter 1 – Animal & Plant Cells
Sub-cellular Structures
Nucleus – controls all the activity of the cell and stores genetic
material.
Mitochondria – respiration occurs here, releasing energy.
Chloroplasts – contain chlorophyll and absorbs light for photosynthesis.
Ribosomes – proteins are synthesised (made) here.
Cytoplasm – a liquid gel where chemical reactions take place.
Cell Wall – made of cellulose, strengthens the cell.
Vacuole – it is full of cell sap which is full of ions which gives it salty
liquid. This keeps the plant fat and turgid.
Cell membrane = controls the movement of substances in and out.
Comparison
Plant cells have vacuoles, chloroplasts & cell walls, whereas animal
cells don’t have these sub-cellular structures.
Plant cells are bigger than animal cells in size.
Plant cells make their own food by photosynthesis, but animal don’t.
, Chapter 1 – Eukaryotes and Prokaryotes
Eukaryotes
- Animal cells and plant cells are Eukaryotes. All animals and including humans, plants, fungi and protista are
- Eukaryotes.
- All Eukaryotic cells have a cell membrane, cytoplasm, and genetic material enclosed in a nucleus.
Prokaryotes Comparison
- Example: Bacteria - Prokaryotes are older and simpler
- In prokaryotic cells, genetic material isn’t enclosed in nucleus. - Prokaryotes are simple and smaller therefore
- The bacterial chromosome is found as a single loop, and may - they can reproduce faster
- have extra small rings of DNA called plasmids, coding for - Eukaryotes have a nucleus, and membrane
- certain features like antibiotic resistance. - bound organelles
- Both have DNA, ribosomes, cytoplasm, and
- cell membranes
- Eukaryotes are larger and more complex
- Prokaryotes are single celled
- Eukaryotes can be multi-cellular
- Prokaryotes have single chromosomes
- (plasmid)
- Eukaryotes have multiple chromosomes
- (DNA in the nucleus)
