Senior Biology - Cells as the basis of life - For additional resources visit: http://www.iheartscience.net

1. biocanvas.net
Cells as the basis of life
Sarah Jones

2. All LIVING things are made of CELLS.
Fibroblasts are cells that help maintain tissue structure by secreting proteins like collagen and elastin - biocanvas.net

3. The Discovery of Cells
In the seventeenth century, Robert Hooke looked
at thin slices of cork under a microscope that he
had made from lenses. He observed small box-like
shapes inside the cork. He called the little boxes
that he saw cells.
marshscience7.blogspot.com

4. http://discovermagazine.com/2015/june/21-leeuwenhoeks-lucky-break

5. Electron Microscopy Images Of Coffee
coffeeguru4iphone.wordpress.com

6. boneresearchsociety.org
SEM Image of Trabecular bone

9. Unicellular organisms – single-celled
organisms.
Multicellular organisms – have specialised
cells that carry out specific functions.
Unicellular Algae – biocanvas.net

10. Carry out all of the functions of life
M ovement
R espiration
S ensitivity
G rowth
R eproduction
E xcretion
N utrition
Unicellular Organisms
Diatom – biocanvas.net

11. Under the five kingdom system cells can be
divided into two basic types.

12. Prokaryotic cells - simple cells without distinct
membrane bound organelles or nucleus.

13. Eukaryotic cells - more complex with
membrane bound organelles and nucleus.

14. Animal Cell

15. • Exist as part of a multicellular organism.
• Specialisation of cells into many types (cell
differentiation).
• Possess nucleus and membrane bound
organelles.

18. Plant Cell
en.wikipedia.org

19. • Exist as part of a multicellular organism.
• Specialisation of cells into many types (cell
differentiation).
• Possess nucleus and membrane bound
organelles.

21. Plant vs Animal
Plant and animal cells have many similarities
because they are both eukaryotic.
They also have some differences:

22. Plasma Membrane
• The surface of exchange for materials
between the inside and outside of the cell.
• IN – oxygen, nutrients and water
• OUT – carbon dioxide, waste and products
such as proteins
http://www.histology.leeds.ac.uk/cell/plasma_membrane.php

23. Plasma Membrane Function
1. Hold cell together
2. Control what goes in and out – diffusion,
osmosis, active transport
3. Protect the cell
4. Allow the cell to recognise and be
recognised – cell signaling and immunity
5. Bind to other cells and molecules
6. A sit for biochemical reactions – enzymes,
areas for reactions

24. en.wikipedia.org

25. Diffusion
• Larger cells require more resources to be
imported and more products to be exported.
• As cells get larger the SURFACE AREA to
VOLUME RATIO gets smaller.
• Increasing cell size – less efficient
exchange process.
www.bbc.co.uk

26. Brownian Motion – the random movement of
particles in a liquid or gas. Due to Brownian
motion particles will diffuse evenly through the
system over time.

27. Diffusion is the passive net movement of
molecules from regions of high concentration
to low concentration.
ekgenius.net/

28. Facilitated diffusion is the passive net
movement of particles from regions of high
concentration to low concentration, through
selectively permeable membrane (plasma
membrane), facilitated by carrier proteins.
ccaoscience.wordpress.com

29. en.wikipedia.org

30. Osmosis
Osmosis is the passive net movement of
water molecules from regions of low solute
concentration to high solute concentration,
through partially/selectively permeable
membrane.
bronxguildlivingenvironment.blogspot.com

31. Osmosis is also movement down a concentration
gradient –we are considering the movement of
water molecules, not the solute molecules.
ekgenius.net/

32. Active Transport
Active transport uses energy (ATP) to move
molecules against a concentration gradient,
using membrane protein pumps.
www.premedhq.com

33. en.wikipedia.org

34. Endocytosis
en.wikipedia.org

35. Exocytosis
commons.wikimedia.org

36. Parts of a Generalised Animal Cell
https://en.wikipedia.org/wiki/Cell_nucleus

37. • Contains the chromosomes (genetic
information) for the cell.
• Controls the activities of the cell.
Nucleus

38. • Double membrane - outer membrane and
inner membrane.
• Inner membrane is folded forming cristae.
• The interior contains an organic matrix
containing chemical compounds.
• Site of aerobic respiration.
Mitochondria

39. Rough Endoplasmic Reticulum
• A membrane system of flattened parallel
cavities which are interconnected and covered
with ribosomes.
• An intracellular transport system.

40. Golgi Apparatus
• Consists of a stack of flattened cavities which
package substances produced by the cell into
vesicles.
• These vesicles can fuse with the cell
membrane (exocytosis) or become
lysosomes (digestive vesicles).

41. Plant Cell Walls
• The main component of plant cell walls is
cellulose.
• Cellulose molecules are arranged in bundles
called microfibrils.
• The function of the plant cell wall is to provide
strength and support the plant.

42. Photosynthesis

43. Chloroplast
biology-themiracleoflife.blogspot.com

44. mrkubuske.wordpress.com

45. Cellular Respiration Plants
www.tvdsb.ca

46. Cellular Respiration Humans
http://mrkubuske.files.wordpress.com

47. Comparing Cellular Respiration and
Photosynthesis
www.accessexcellence.org

48. www.bbc.co.uk

49. Prokaryotic organisms are commonly called
bacteria.
They are cells with a simple structure.
They have no membrane around the nucleus
and lack any membrane bound organelles.

50. Blue-green bacteria make their own food by
photosynthesis.

51. en.wikipedia.org

52. Prokaryotic Cell Parts
• Cell Wall – protective protein-based coating.
• Plasma Membrane – selectively permeable.
• Pili – attach to other bacteria for DNA transfer.
• Cytoplasm – contains enzymes for metabolic
reactions.
• Nucleoid – closed-loop of bacterial DNA.
• Ribosomes – protein synthesis – transcription
and translation.
• Flagella – causes movement.

53. en.wikipedia.org

54. Prokaryotic Reproduction – Binary Fission
http://evolution-textbook.org/content/free

55. Cell Division
• For an organism to grow larger it needs to
produce more cells – and each new cell
needs a copy of the organism’s DNA.
• Tissue Repair
• Asexual Reproduction
commons.wikimedia.org

56. Mitosis

57. commons.wikimedia.org