1. Cell Diversity

2. Previous Exam Questions Higher Level Ordinary Level 2006 Q6 2007 Q11, Q14 2004 Q8 2006 Q14 2003 Q4 2003 (Sample)

3. Tissue Tissue – A tissue is a group of similar cells that carry out the same function.

4. Plant Tissue Plant Tissues: (4 main types) Dermal – e.g. epidermis (skin) Dermal – e.g. epidermis (skin) Vascular – e.g. xylem, phloem Vascular – e.g. xylem, phloem Ground – e.g. spongy mesophyll in leaf Ground – e.g. spongy mesophyll in leaf Meristematic – e.g. cells in root tip that divide by mitosis. Meristematic – e.g. cells in root tip that divide by mitosis.

5. Animal Tissue Animal Tissues: (4 main types) Epithelial – e.g. epidermis (skin) Epithelial – e.g. epidermis (skin) Connective – e.g. blood, bone Connective – e.g. blood, bone Nervous Nervous Muscular Muscular

6. Plant Tissues - Dermal Dermal Tissue: e.g. Epidermis - Dermal tissue surrounds and encloses plants.

7. Plant Tissues - Dermal Location: - Dermal tissue is found in the leaf, stem and roots.

8. Plant Tissue - Dermal Appearance: - Epidermal tissue usually contains rectangular cells. - The cells have thick, strong walls with a waterproof layer called the cuticle on the outer surface.

9. Plant Tissue - Dermal Function: - To protect the plant. - If a cuticle is present, it prevents water loss from the plant.

10. Plant Tissue - Vascular Vascular Tissue: e.g. xylem, phloem  Vascular tissue transports materials around the plant.  2 types of vascular tissue - Xylem – transports water + dissolved minerals. - Phloem – transports food around plant

11. Plant Tissue - Vascular Location: - Xylem and phloem are tubular tissues. - They are found in all parts of the plant including the roots, stems & leaves. - They are arranged in bundles called vascular bundles

12. Vascular Tissue

13. Plant Tissue - Vascular Xylem - Dead tissue that transports water. - There are 2 types of xylem tissues: - Tracheids - Tracheids - Vessels - Vessels

14. Plant Tissue – Vascular (xylem) Appearance - Tracheids Tracheids are long narrow tubes formed when the walls of individual cells overlap. Tracheids are long narrow tubes formed when the walls of individual cells overlap. Their walls have small openings called pits that allow water to pass from cell to cell. Their walls have small openings called pits that allow water to pass from cell to cell. Found in the wood of conifers such as pine trees. Found in the wood of conifers such as pine trees.

15. Tracheids

16. Plant Tissue – Vascular (xylem) Appearance – Vessels Vessels are larger than tracheids. Vessels are larger than tracheids. They form a continuous hollow tube. They form a continuous hollow tube. Found in flowering plants, especially in trees where they form the wood. Found in flowering plants, especially in trees where they form the wood.

17. Plant Tissue – Vascular (xylem) Function: Tracheids and vessels both transport water and salts Tracheids and vessels both transport water and salts Xylem tissue also strengthens the plant. Xylem tissue also strengthens the plant.

18. Questions???? What is a tissue? What is a tissue? Name 2 types of animal tissues. Name 2 types of animal tissues. Name 2 types of plant tissues and state their functions. Name 2 types of plant tissues and state their functions. Name 2 types of xylem tissues and state their functions. Name 2 types of xylem tissues and state their functions.

19. Plant Tissue – Vascular (Phloem) Phloem:Appearance: Have many cells that form long tubes called sieve tubes. Have many cells that form long tubes called sieve tubes. The walls at the end of each phloem have many pores – sieve plates. The walls at the end of each phloem have many pores – sieve plates. Have companion cells containing nuclei. Have companion cells containing nuclei.

20. Plant Tissue – Vascular (Phloem)

21. Function: Transports food from the photosynthetic regions to the rest of the plant. Transports food from the photosynthetic regions to the rest of the plant. Companion cells control the sieve tube element. Companion cells control the sieve tube element.

22. Animal Tissues Connective tissue: Joins and supports other parts of the body. Joins and supports other parts of the body. Example – Adipose tissue, blood, bone Example – Adipose tissue, blood, bone Nervous tissue: Consists of nerve cells called neurons that carry electrical impulses to and from the brain. Consists of nerve cells called neurons that carry electrical impulses to and from the brain.

23. Blood

24. Questions???? Name the 2 types of vascular tissues. Name the 2 types of vascular tissues. How would you describe the appearance of phloem? How would you describe the appearance of phloem? What is the function of phloem? What is the function of phloem? Give 2 examples of connective tissue. Give 2 examples of connective tissue.

25. Tissue Culture Tissue Culture: Is the growth of tissues on an artificial medium outside an organism. Is the growth of tissues on an artificial medium outside an organism. Growth of cells can be:  In-vitro – outside the body  In-vivo – in the body

26. Tissue Culture In-vitro growth requires: Correct nutrients e.g vitamins, minerals etc Correct nutrients e.g vitamins, minerals etc Growth hormones Growth hormones Suitable temperature Suitable temperature Oxygen Oxygen Sterile environment (no bacteria) Sterile environment (no bacteria)

27. Tissue Culture 2 examples of tissue culture:  Micro-propagation  Use of monoclonal antibodies in cancer research

28. Tissue Culture Micro-propagation:  Is the growth of large numbers of identical plants from pieces of an original plant.  The new plants are genetically identical (clones).

29. Tissue Culture Benefits of micro-propagation:  Huge numbers of plants can be formed in a very short time.  New plants are genetically identical  Process is a cheap way to produce new plants

30. Tissue Culture Cancer research:  Antibodies grown in an artificial medium are called monoclonal antibodies.  Examples include; detecting cancer cells, testing for drugs in blood or urine.

31. Organs Organ:  Is a structure composed of 2 or more tissues that work together to carry out one or more functions Examples:  Plant organs – roots, stems, leaves,  Animal organs – brain, heart, lungs

32. Organs Organ system:  Consists of one or more organs working together to carry out one or more functions. Examples:  Digestive system – mouth, stomach, etc  Circulatory system – heart, blood, lymph vessels etc

33. Organ Systems

34. Questions???? What is meant by tissue culture? What is meant by tissue culture? Distinguish between in-vitro and in-vivo. Distinguish between in-vitro and in-vivo. Name 3 conditions that in-vitro growth requires? Name 3 conditions that in-vitro growth requires? Give 2 examples of tissue cultures. Give 2 examples of tissue cultures. Describe micro-propagation. Describe micro-propagation. Name 2 organs & 2 organ systems Name 2 organs & 2 organ systems