AREA OF STUDY 1 Cells in action

1. AREA OF STUDY 1 Cells in action Pete Hamilton Sandringham College

2. Biology: • is a natural science concerned with the study of life living organisms their structure, function, growth, origin, evolution, distribution, taxonomy and interrelationships.

4. Biology: Utilises Observation and the Scientific Method

5. Flying Blind – LazzaroSpallanzani and Bats • In 1790 an Italian scientist, LazzaroSpallanzani observed that owls were not able to fly in complete darkness whilst bats had no difficulty. • He experimented by isolating the bats ability to see, smell, vocalise and hear. • Spallanzanidiscovered that bats without the use of vision or smell could still navigate and avoid objects, however those with plugged ears, particularly just one plugged ear, could not. • He concluded bats see by hearing. • Not many people believed him.

6. It was not until the 1930’s that an American scientist Donald Griffin would finally determine the mechanism for bats navigation. • Griffin, using experiments with Little Brown Bats, determined that the bats were emitting a series of very high-pitched clicks that increased as they approached prey. • These clicks were echoed back to the bat from the objects and the bats were using these echoes to determine the precise location of the object. • Echo Location

7. The Scientific Method • Based on Observation • Hypotheses are generated • Possible explanations for an observed phenomena • Hypotheses can be either supported or rejected by experiments • Experiments are designed and conducted • Results are analysed • Conclusions are deduced • Results are reported and published • Method is replicated and tested by others

8. Organisms are living things • How do we know that something is living or non-living? • Animals: - • Plants: - • Mould: -

9. Seven Characteristics of Living Organisms: • Movement • Respiration • Sensitivity • Growth • Reproduction • Excretion • Nutrition MRS GREN

10. Living, dead or non living? • Non- Living • In order to consider something non-living, it must not have any of the 7 characteristics of living things. or • It was living or dead and has been processed(chemically altered) Dead In order to consider something dead, it must have been alive at one time and it no longer has any of the 7 characteristics of living things.

11. Living, dead or non living?

12. Cell Intro video

13. The Cell Theory • All living things are made up of one or more cells – cells are very small • There can be different kinds of cells within living organisms. • (skin cells, brain cells, muscle cells) • Cells are the functional unit of all living things • This means that they are where all the action happens, they process food, give structure and many other things.

14. The Cell Theory • All cells come from pre-existing cells.

15. Cells and organisms vary greatly in size

16. Units of measurement: Single or multicelled? 1 micrometer = 1 micron 1 μm = 1 μm 1 micrometer = 0.001 millimeter 1 μm = 0.001 mm 1 micrometer = 0.0001 centimeter 1 μm = 0.0001 cm 1 micrometer = 1.0 × 10-6meter 1 μm = 1.0 × 10-6 m Unicellular organisms: composed of only 1 cell- Microscopic Euglena 10 microns Multicellular organisms: composed of many cells, cells specialised - Microscopic to Macroscopic Hydra 10,000 microns

17. Cells and Microscopes • There are several types of microscopes, each can allow us to view cells differently and to a different degree.

18. Cell Structure • There are many types of cells and each has its own structure and purpose. • each cell has features that help it carry out its purpose. • (e.g Nerve cells)

19. Properties of cells • Despite cells having different functions, all cells have some things in common. • Plasma or Cell membrane - separates the cell from it’s external environment. • Cytoplasm – Jelly like holds all the organelles, ions, salt, enzymes, nucleus and is 90% water. Cytosol is the fluid part of the cytoplasm. • DNA- genetic material that directs the cell’s activities. • Organelles – Components inside the cells cytoplasm that perform different functions.

20. Prokaryotes Vs Eukaryotes • PRO • More primitive cells • Lack membrane bound organelles • Smaller than Eukaryotic cells • EU • Complex cells • Have membrane bound specialised organelles • Larger than prokaryotic cells

21. Prokaryote cells simple cells (example: E. coli) • capsule: slimy outer coating • cell wall: tougher middle layer • cell membrane: delicate inner skin

22. Prokaryote cells (example: E. coli) • cytoplasm: inner liquid filling • DNA in one big loop • pilli: for sticking to things • flagella: for swimming • ribosomes: for building proteins

23. Prokaryote lifestyle • unicellular: all alone • colony: forms a film • filamentous: forms a chain of cells

24. Prokaryote Feeding • Photosynthetic: energy from sunlight • Chemosynthetic: energy from chemicals

25. Prokaryote Feeding • Disease-causing: feed on living things • Decomposers: feed on dead things

26. Prokaryote E. coli bacteria on the head of a steel pin.

27. Eukaryotes • DNA is located inside the nucleus as thread like chromosomes • Specialised organelles each performing a specific function

28. Eukaryotes are larger and more complex • Have organelles • Have chromosomes • can be multicellular • include animal and plant cells Animal cells Intro

29. Organelles are membrane-bound cell parts • Mini “organs” that have unique structures and functions • Located in cytoplasm

30. Cell Structures • Cell membrane • delicate lipid and protein skin/membrane around cytoplasm • found in all cells

31. Nucleus • a membrane-bound sac evolved to store the cell’s chromosomes (DNA) • has pores: holes

32. Nucleolus • inside nucleus • location of ribosome factory • RNA

33. mitochondrion • Releases the cell’s energy • the more energy the cell needs, the more mitochondria it has

34. Mitochondria Mitochondria

35. Ribosomes • build proteins from amino acids in cytoplasm • may be free-floating, or • may be attached to ER • made of RNA

36. Endoplasmic reticulum • may be smooth: builds lipids and carbohydrates • may be rough: stores & transports proteins made by attached ribosomes

38. Golgi Complex • takes in sacs of raw material from ER • sends out sacs containing finished cell products • Golgi Apparatus

39. Lysosomes • sacs filled with digestiveenzymes • digest worn out cell parts • digest food absorbed by cell

41. Centrioles • pair of bundled tubes • organize cell division

42. Cytoskeleton • made of microtubules • found throughout cytoplasm • gives shape to cell & moves organelles around inside.

43. Cytoskeleton • cytoplasmic streaming

44. Structures found in plant cells • Cell wall • very strong • made of cellulose • protects cell from rupturing • glued to other cells next door

45. Vacuole • huge water-filled sac • keeps cell pressurized • stores starch

46. Chloroplasts • filled with chlorophyll • turn solar energy into food energy

47. Chloroplasts

48. How are plant and animal cells different?

50. Prokaryotes Eukaryotes simple and easy to grow can specialize fast reproduction multicellularity all the same can build large bodies Advantages of each kind of cell architecture