1. National 5: Unit 1 revision

2. Chapter 1: Cell Structure
Unit 1: Cell biology
Chapter 1: Cell Structure

7. Questions What are the basic units of life?
Draw and label an animal, plant, fungal and bacterial cell
Write a comparison of a fungal cell and a green plant cell
Write the function of the: Nucleus, Cytoplasm, Cell membrane, Mitochondria, Ribosomes, Cell wall, Vacuole, Chloroplasts, Large Circular chromosome, plasmid
Explain why a plant’s root cells do not have chloroplasts
How does the cell wall in a plant cell, fungal cell and bacterial cell compare?

8. Field of view
In order to calculate the length of a cell, we can COUNT the number of cells along the DIAMETER of the microscope then perform a calculation.
If there are 8 cells in the FIELD OF VIEW and the diameter is 2mm- How would we work out the length of one cell?

9. The diagram below shows onion cells as observed under a microscope at a magnification of 100 X.
The diameter of the field of view is 300 micrometres. The average width of each cell in micrometres is
A 0.38
B 0.75
C 375
D 75

10. The diagram below shows onion cells as observed under a microscope at a magnification of 100 X.
The diameter of the field of view is 300 micrometres. The average width of each cell in micrometres is
A 0.38
B 0.75
C 375
D 75

11. The diagram below shows a group of cells as seen under a microscope.
The field of view was 2 mm in diameter.
Calculate the average length and width of the cells.
Average length __________ mm
Average width __________ mm

12. The diagram below shows a group of cells as seen under a microscope.
The field of view was 2 mm in diameter.
Calculate the average length and width of the cells.
Average length 0.4 mm
Average width 0.2mm

13. Total magnification
In order to work out the TOTAL MAGNIFICATION of a microscope we must multiply the power of the EYE PIECE LENS by the power of the OBJECTIVE LENS.
If we know the TOTAL MAGNIFICATION we can use DIVISION to work out the strength of the EYEPIECE LENS or the OBJECTIVE LENS

14. Copy and complete x5 x60 x10 x35 x15 x65 x40 x400 x25 x275
Eye piece lens
Objective lens
Total magnification x5
x60
x10
x35
x15
x65
x40
x400
x25
x275

15. Chapter 2: Transport across cell membranes
Unit 1: Cell biology
Chapter 2: Transport across cell membranes

16. Plasma membrane Phospholipid Bilayer Fluid Mosaic Model Cell Membrane
Controls entry and exit of substances into and out of cell
Selectively permeable

17. Diffusion- definition, importance (uni/multi)
Osmosis- definition, osmosis in action
Active Transport- definition, examples

18. Name the two substances present in the cell membrane
Draw and label a diagram of the cell membrane including the 2 substances mentioned
Write down the definition of: Selectively permeable, Diffusion, Osmosis, Active Transport
Explain why diffusion is important in: a) Unicellular b) Multicellular organism
Give an example of a situation where a cell uses a) Diffusion b) Osmosis c) Active transport
Define the terms passive and active
Describe the role of the proteins in active transport
Give an account of what happens to an animal cell placed in a) pure water b) isotonic solution c) salt solution

19. Chapter 3: Producing new cells
Unit 1: Cell biology
Chapter 3: Producing new cells

20. All living things contain genetic information
Cell
Nucleus
2 Matching sets of chromosomes
Genes
DNA

21. Chromosome Complement
SEXUALLY reproducing animals have PAIRS
Each species CHROMOSOME COMPLEMENT

22. Haploid and Diploid
Every cell (except RBS and gametes) contain chromosome complement
DIPLOID (2n)- 2 sets
HAPLOID- (n)- 1 set

23. Cell Division (aka Mitosis)
MITOSIS is the process by which the nucleus of a cell divides into TWO daughter nuclei, each of which contains EXACTLY the same number of chromosomes as the original parent cell.

24. Importance of Mitosis Unicellular- Reproduction
Multicellular- Growth, Repair, Regeneration
Diploid complement maintained- daughter cells have all the genes to function correctly

25. Stages of Mitosis

26. Loss of control Orderly process of cell division can go wrong
DNA (oncogenes) can become damaged- MUTATIONS
Cells don’t die when they should- new cells made but not needed
Extra cells form TUMOUR

27. Examples of cancer causing agents!
UV rays from the sun.
UV rays from sun-beds,
Chemicals in Cigarettes.
Radiation.
Diet.
Lack of exercise.
Chemicals such as DDT.

28. Cell culture
When a supply of a certain type of cell is needed (stem cell, yeast or bacteria), Cultures of the cell can be grown.

29. Why cell culture? To learn about cell division Baking/brewing
Testing drugs
Stem cell research
Grow new cells
Diagnose illness

30. Cell culture To grow cells in the lab you need:
A suitable growing medium
Availability of oxygen
A suitable temperature
A suitable pH level
Aseptic Conditions

31. What is a chromosome and where are they found in cells?
Define the terms: a) Haploid b) Diploid c) Chromosome Complement
What is the definition of mitosis?
Explain why it is important that the chromosome complement is maintained during mitosis.
Explain the importance of mitosis in a) Unicellular b) Multicellular organisms
Using diagrams, give a description of each stage of mitosis
State the role of the spindle fibres during mitosis
Explain what can happen if control of cell division is lost
What can increase the risk of loss of control of cell division?
What can cell culture be used for?
Explain why cell culture requires aseptic conditions
Give 3 examples of what you can do to ensure aseptic conditions are maintained

32. Chapter 4: DNA and the production of proteins
Unit 1: Cell biology
Chapter 4: DNA and the production of proteins

33. DNA Chromosomes- Nucleus – made of DNA
DNA- genetic code- recipe/blueprint

34. Structure of DNA DNA= TWO long stranded molecules Ladder Double Helix
Monomer= NUCLEOTIDES

35. Nucleotides
PHOSPHATE
BASE
(deoxyribose) SUGAR

36. Complementary Base Pairs
Weak Hydrogen bonds between bases
Complimentary base pairs- SHAPE
Adenine-Thymine
Guanine-Cytosine
Always Together
Good Company

37. Building Proteins Amino acids are building blocks of proteins
3 x bases= TRIPLET
“Codeword” for AMINO ACIDS
Approx 20 amino acids
Amino acids join to make protein
Order of amino acids determines protein

38. Protein Synthesis
The genetic code in the DNA is copied by a messenger (mRNA)
The mRNA carries a copy of the code out of the nucleus to the ribosomes
The ribosomes select the correct amino acids.
The amino acids are joined together to make a specific protein.
Examples of proteins include hormones, enzymes, antibodies and structural proteins.

39. State the role of DNA in cells
Describe the structure of DNA using the terms double helix and base
Identify the 4 DNA bases
What is meant by the term complimentary base pairs?
What are the complimentary base pairs?
What is the genetic code?
How many amino acids are there?
How many bases code for 1 amino acid?
What is the main difference between DNA and mRNA
State the location in the cell where amino acids are assembled into proteins
Give an account of protein synthesis