Module 4-Level of Organizationin SI.pptx

SCIENCE

1. Levels of Organization

2. Levels of Organization studied in BIOLOGY…

3. Learning Intentions 3 By the end of this Key Area you should be able to Explain that specialisation of cells leads to the formation of a variety of cells which are adapted to perform a specific function. Give examples of specialised cells in both plants and animals.

4. From the smallest level… 1. ATOMS The smallest unit of matter that cannot be broken down into anything simpler by chemical means. 2. Molecules The smallest units of most compounds formed by the chemical bonding of atoms. 3. Organelles Specialized structures that perform important cellular functions within cells. 4. Cell The smallest unit of life – collections of living matter enclosed by a barrier that separates them from their surroundings.

5. From the smallest level… 5. Tissues Groups of similar cells that perform a particular function. 6. Organs Groups of tissues that work together to perform closely related functions. 7. Organ Systems Groups of organs that work together to perform closely related functions. 8. Organisms Living things composed cells (multicellular organisms). Species = a group of organisms so similar to one another that they can breed and produce FERTILE OFFSPRING.

6. …to the largest level . 9.Population Groups of individuals of the same species that live in the same area. 10. Community Groups different populations that live together in a defined area. 11.Ecosystem Groups of all the organisms that live in a particular place, together with their nonliving environment. 13. Biosphere Part of the Earth in which life exists including land, water, air and atmosphere. 12. Biome Groups of ecosystems that have the same climate and similar dominant communities

7. All organisations have a LEVEL OF ORGANISATION 9/17/2023 7 Mrs Smith - National 5 Biology Cell  Tissue  Organ  B ody System  Organism

8. Level of organisation: Cell. In a unicellular organism The Cell is defined as the basic unit of life: It is the smallest unit that can lead to independent life. Unicellular organisms for example in an amoeba do not have a level of organism as they are only made of one cell. 9/17/2023 8 Mrs Smith - National 5 Biology

9. Level of organisation: Cell. In a multicellular organism The body of a multicellular organism consists of a large number of cells. It would be inefficient for every one of these cells to carry out every function essential for the maintenance of life. 9/17/2023 9 Mrs Smith - National 5 Biology Instead a division of labour is achieved by the cells being organised into tissues and the tissues being organised into tissues and the tissues being united to form tissues Cell  Tissue  Organ

10. 9/17/2023 10 Mrs Smith - National 5 Biology Level of organisation: Cell. Specialisation of cells Yes that are all cells but why do they all look so different?

11. 9/17/2023 11 Mrs Smith - National 5 Biology Level of organisation: Cell. Specialisation of cells Yes that are all cells but why do they all look so different and the do look very different. Cells have adapted to vary in size, shape or function depending on their role in the organism. STRUCTURE IS RELATED TO FUNCTION!

12. 1. Specialised animal cells There are hundreds of specialised animal cells which have evolved a unique structure for carrying out specific roles in the animal. The following slides show just a few examples… 9/17/2023 13 Mrs Smith - National 5 Biology

13. Specialised Animal Cells Muscle cells – enable us to move. Muscle cells bring parts of the body closer together. They contain protein fibres that can contract when energy is available, making the cells shorter.

14. Specialised Animal Cells Fat cells – store energy Fat cells have a very small cytoplasm leaving more room to store as much fat as possible. There are very few mitochondria because a fat cell needs very little energy. A fat cell has the potential to expand to 1000X its normal size as it is filled with fat. Fat cells can survive for upto 10 years before they eventually die.

15. Specialised Animal Cells Sperm – male gamete for reproduction

16. Specialised Animal Cells Egg – female gamete for reproduction Cytoplasm containing yolk Layer of jelly Nucleus The egg cells has a specialised structure, it is huge compared to the sperm, in fact it is the only cell, visible with the human eye. It is designed to be fertilised by the sperm as it carries the mothers DNA in the nucleus The primary purpose of the yolk sac in mammals is to provide nourishment for the embryo at the earliest stages of development (until the placenta is formed).

17. Specialised Animal Cells Nerves – transmits electrical signals to allow organisms to respond to their environment

18. Found on the surfaces of the body and organs, for protection, secretion, absorption and transport The cell structure is tightly packed, box-like shapes which form continuous sheets (like bricks fitting together in a wall). These line different parts of the body. Such as.. Inside the mouth (e.g. cheek cells) Line organs (e.g. stomach) Surround organs. Make the outer layer of the skin Specialised Animal Cells Epithelial Cells line different parts of the body

19. Red blood cells – Carry oxygen to all the other cells of the body. Specialised Animal Cells Red blood cells to carry oxygen to all body cells Biconcave shape, increases surface area to volume ratio allowing faster diffusion of oxygen. Cytoplasm contains no nucleus allowing more room for haemoglobin. Flexible cell membrane allows red blood cell to be squeezed through narrow capillaries without damage.

20. Specialised Animal Cells White blood cells to fight infections There are different types of white blood cells, all of which have a different structure depending on the role they have in protecting the body. Neutrophils have the mission of “search and destroy”. They can change shape to engulf bacteria, diseased or dead cells and digestive them with special enzymes. Or they can secrete a lethal cloud of toxic chemicals (peroxide & chlorine bleach). A neutrophil can kill a hundred bacteria with one of these bursts, but the chemicals are also fatal to the neutrophil itself. They are the “suicide bombers” of our immune system. Lymphocytes have a large nucleus with very little cytoplasm. There are three main types of lymphocytes critical for specific immune responses. And development of immunity

21. Designed to stop Lung Damage They line all the air passages in the lungs. They have tiny hairs called cilia. Hairs sweep mucus with trapped dust and bacteria back up the throat. Nucleus cilia Specialised Animal Cells Ciliated epithelium to sweep debris away from lungs

22. 2. Specialised plant cells Plants also have man specialised cells which have evolved a unique structure for carrying out specific roles in the plant. The following slides show just a few examples…

23. These cells are found on the top surface of a leaf. The are adapted to carryout photosynthesis. Palisade cells are tall (columnar shaped) this provides a large surface area to absorb water and minerals. Packed with chloroplasts which store light energy from the sun to help the plant make food during photosynthesis. Nucleus Chloroplasts Specialised plant cells Palisade mesophyll cells for photosynthesis

24. The underside of the leaf has pores called stomata; these are the site of transpiration (water loss) and gas exchange (CO2 and O2 during photosynthesis). Alongside each stomata is 2 guard cells. If there is high water pressure guard cells become swollen causing the stomata to open. If there is low water pressure the guard cells become shrunken causing the stomata to close. Specialised plant cells Guard Cells– Transpiration in plants

25. Found in a plant root. Root hairs are long extended cells adapted for absorbing water and minerals from the soil. Thin cell wall makes it easy for minerals to pass through. It has a large surface are which helps it with absorption Vacuole Cell membrane thin cell wall Specialised plant cells Root hair cells for water and mineral absorption

26. The xylem cells/vessels form hollow tubes that run from the roots, up the stem and into the leaves. Xylem vessels have thick cell walls, strengthened by internal bands of lignin in order to withstand pressure changes as water moves through the plant. ​ Specialised plant cells Xylem – Water transport in plants

27. The end walls of phloem cells have holes in them that allow the cytoplasm containing dissolved sugar to flow from cell to cell. Due to this, these cells are referred to as phloem sieve tubes. ​ ​ Alongside each sieve tube cell is a companion cell which has a nucleus that can repair the sieve tube if it is damaged. ​ Specialised plant cells Phloem and companion cells– Sugar transport

28. We have demonstrated there are lots of different types of specialised cells in both plant and animal cells. As we get further into the course you will learn about some of these in more detail for example when we do transport in plants you will learn about phloem and xylem. Don’t panic if you can’t remember all these cell types. The take home message is…. cells have adapted a structure to meet their required function . Try to learn at least 2 examples of specialised cells from each animals and plants. Specialised cells

29. Key Area 2.1: Producing New Cells 2.1d: Part 1 – Specialisation of cells leads to the level of organisation National 5 Biology Unit 2: Multicellular Organisms 9/17/2023 30 Mrs Smith - National 5 Biology

30. Level of organisation: Cells  Tissues 9/17/2023 31 Mrs Smith - National 5 Biology We have learned there are lots of different specialised cells in plants and animals. In fact there are over 220 different cell types in the human body. Each type of cells is adapted to carry out a particular function, either solely, but usually by forming a particular tissue, this is because; it is very inefficient for each cell to carry out every function essential for the maintenance of life. Instead a division of labour is achieved by the cells being organised into tissues and the tissues being organised into tissues and the tissues being united to form organs Cell  Tissue  Organ

31. National 5 Biology 9/17/2023 32 Mrs Smith - National 5 Biology A tissue is a group of cells specialised to perform a particular function (or functions). The table below shows some animal cells and the tissues they make. Level of organisation in animals Cells  Tissues

32. National 5 Biology 9/17/2023 33 Mrs Smith - National 5 Biology The table below shows some plants cells and the tissues they make. Level of organisation in plants Cells  Tissues

33. Level of organisation: Tissues  O rgans 9/17/2023 34 Mrs Smith - National 5 Biology An organ is a structure composed of several different tissues co-ordinated to perform one or more functions. Cell  Tissue  Organ The stomach is an organ that digests food. Muscle tissues, nerve tissue, and blood tissue are just some of the types of tissue that make up the stomach.

34. Level of organisation: In animals Tissues  O rgans 9/17/2023 35 Mrs Smith - National 5 Biology Cell  Tissue  Organ

35. Level of organisation: In animals Tissues  O rgans 9/17/2023 36 Mrs Smith - National 5 Biology Cell  Tissue  Organ Plants also have reproductive organs: these vary in different plant species and can include flowers (containing the sex organs in plants that sexually reproduce) , seeds and fruit.

36. Level of organisation: In animals Organs  Body Systems 9/17/2023 37 Mrs Smith - National 5 Biology Cell  Tissue  Organ  Body System Organs are then grouped together and used to make up our body systems. Body systems, allow us to breath, eat and reproduce. And much more, Body systems perform everything animals and humans need to live and survive. There are 11 main body systems

37. Nervous System – Makes you feel things The main organs in the nervous system are the brain, spinal cord & nerves. The brain sends messages to the body, and the nerves make you feel things. The brain controls everything    The Nervous system is like the telephone system because the phone sends messages to other people like the brain sends messages to the nerves.

38. Circulatory system – Pumps blood round our body. The majors parts of the circulatory system are the heart, arteries and veins. The heart pumps blood to the arteries. The arteries take the oxygenated blood to the muscles. The veins take blood back to the heart, which then releases carbon dioxide in the lungs. 

39. Muscular System. Gives body strength. The muscular system includes three types of muscles. Smooth muscles, which are found on the walls of internal organs Cardiac Muscles, which are found only in the heart Skeletal muscles, which help strengthen the body and connect to bones

40. Skeletal System. Shape, support and protection. Our system is made up of the 206 different bones of the body. The skeletal system gives you shape and support. It protects other parts of your body, like the brain, lungs, heart and liver.  

41. Level of organisation: In plants Organs  Organ Systems 9/17/2023 42 Mrs Smith - National 5 Biology Cell  Tissue  Organ  Body System Vascular Plants have 2 main organ systems

42. Interactions with other body systems B ody Systems  Organism All of the systems within the body interact with one another to keep an organism healthy. Although each system has specific functions, they are all interconnected and dependent on one another. e.g. The nervous system controls various organs of the body directly. The brain also receives information from many organs of the body and adjusts signals to these organs to maintain proper functioning. Cell  Tissue  Organ  Body System  Organism

43. Th organism acts as an integrated whole For a complex multicellular organism to lead an independent life, all of its cells, tissues, organs and systems must operate in close co-ordination with each playing its particular role harmoniously as part of an integrated whole.

44. Cell to Biosphere: It’s important to remember that all these levels relate to each other

45. Biological Levels of organisation

46. And again from the teeny tiny to the globe 9/17/2023 Mrs Smith - National 5 Biology 47