Section 1 The Diversity of Cells

1. Section1 The Diversity of Cells Chapter C1 Objectives • State the parts of the cell theory. • Explain why cells are so small. • Describe the parts of a cell.

2. Section1 The Diversity of Cells Chapter C1 Cells and the Cell Theory • The Cell Theory states: • All organisms are made of one or more cells. • The cell is the basic unit of all living things. • All cells come from existing cells.

3. Section1 The Diversity of Cells Chapter C1 Cell Size • Most cells are too small to be seen without a microscope. • Many Small Cells Most cells are small because food and waste must pass through the cell surface.

4. Section1 The Diversity of Cells Chapter C1 Parts of a Cell • The Cell Membrane and CytoplasmAll cells are surrounded by a cell membrane. Thecell membraneis a protective layer that covers the cell’s surface and acts as a barrier. • Inside the cell is a fluid. This fluid and almost all of its contents are called cytoplasm.

5. Section1 The Diversity of Cells Chapter C1 Parts of a Cell, continued • Organellesare structures that perform specific functions within the cell. • Genetic MaterialAll cells contain DNA at some point in their life. DNA is genetic material that carries information needed to make new cells and new organisms. • The DNA is enclosed inside an organelle called thenucleus.

6. Section1 The Diversity of Cells Chapter C1 Two Kinds of Cells • Cells with no nucleus are prokaryotic. • Cells that have a nucleus are eukaryotic.

7. Section1 The Diversity of Cells Chapter C1 Prokaryotes: Eubacteria and Archaebacteria • Prokaryotesare single-celled organisms that do not have a nucleus or membrane-bound organelles. • Bacteria is an example of a prokaryote.

8. Section1 The Diversity of Cells Chapter C1 Prokaryotes • The image below shows the DNA, cell membrane, and cell wall of a typical bacterial cell. The flagellum helps the bacterium move.

9. Section1 The Diversity of Cells Chapter C1 Eukaryotic Cells and Eukaryotes • Eukaryotic cells have a nucleus and other membrane-bound organelles. Most eukaryotic cells are microscopic, but are about 10 times larger than bacterial cells. • Organisms made of eukaryotic cells are calledeukaryotes.

10. Section1 The Diversity of Cells Chapter C1 Eukaryotic Cells and Eukaryotes • Many eukaryotes are multicellular, which means that they are made of many cells. • Examples of multicellular eukaryotes are animals (including humans), plants, mushrooms, and algae. Examples of single-celled eukaryotes are amoebas and yeasts.

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12. Section2 Eukaryotic Cells Chapter C1 Objectives • Identify the different parts of a eukaryotic cell. • Explain the function of each part of a eukaryotic cell.

13. Section2 Eukaryotic Cells Chapter C1 Cell Wall • Some eukaryotic cells have cell walls. Acell wallis a rigid structure that gives support to a cell. The cell wall is the outermost structure of a cell. • Plants and algae have cell walls made of a complex sugar called cellulose. The cell walls of plant cells help plants retain their shape.

14. Section2 Eukaryotic Cells Chapter C1 Cell Membrane • All cells have cell membranes. The cell membrane is a protective barrier that encloses a cell. • The cell membrane is the outermost structure in cells that lack a cell wall. In cells that have a cell wall, the cell membrane lies just inside the cell wall. • The cell membrane contains proteins, lipids, and phospholipids.

15. Section2 Eukaryotic Cells Chapter C1 Cell Membrane, continued • Lipids are a group of compounds that do not dissolve in water. Lipids are “water fearing” or hydrophobic. • Phospholipids are lipids that contain phosphorus. The phosphorus containing ends of phospholipids are “water loving” or hydrophilic.

16. Section2 Eukaryotic Cells Chapter C1 Cell Membrane, continued • The cell membrane is made of two layers of phospholipids. It allows nutrients to enter and wastes to exit the cell.

17. Section2 Eukaryotic Cells Chapter C1 Cytoskeleton • The cytoskeleton is a web of proteins in the cytoplasm. It acts as both a muscle and a skeleton. • The cytoskeleton keeps the cell’s membranes from collapsing and helps some cells move.

18. Section2 Eukaryotic Cells Chapter C1 Nucleus • The nucleus is a membrane-bound organelle that contains the cell’s DNA. DNA contains the information on how to make a cell’s proteins.

19. Section2 Eukaryotic Cells Chapter C1 Ribosomes • Organelles that make proteins are calledribosomes.Unlike most organelles, ribosomes are not covered by a membrane. • All cells need proteins to live. All cells have ribosomes.

20. Section2 Eukaryotic Cells Chapter C1 Endoplasmic Reticulum • Theendoplasmic reticulum(ER) is a system of folded membranes in which proteins, lipids, and other materials are made. • The ER is part of the internal delivery system of the cell. Substances move through the ER to different places in the cell.

21. Section2 Eukaryotic Cells Chapter C1 Endoplasmic Reticulum, continued • Endoplasmic reticulum is either rough ER or smooth ER. The part of the ER covered in ribosomes is rough ER. ER that lacks ribosomes is smooth ER.

22. Section2 Eukaryotic Cells Chapter C1 Mitochondria • Amitochondrionis the organelle in which sugar is broken down to produce energy. Mitochondria are the main power source of a cell. • Mitochondria are covered by two membranes, as shown at right.

23. Section2 Eukaryotic Cells Chapter C1 Chloroplasts • Chloroplasts are organelles in plant and algae cells in which photosynthesis takes place. • Chloroplasts are covered by two membranes, as shown at right.

24. Section2 Eukaryotic Cells Chapter C1 Golgi Bodies • The organelle that packages and distributes proteins is called theGolgi bodies.The Golgi bodies chnages the lipids and proteins so that they can do different jobs within a living thing.

25. Section2 Eukaryotic Cells Chapter C1 Cell Compartments • The bubble that forms from the Golgi complex membrane is a vesicle. Avesicleis a small sac that surrounds material to be moved into or out of cell. • Vesicles also move material within a cell. Vesicles carry new proteins from the ER to the Golgi complex. Other vesicles distribute material from the Golgi complex to other parts of the cell.

26. Section2 Eukaryotic Cells Chapter C1 Cellular Digestion • Lysosomes are vesicles found mainly in animal cells that are responsible for digestion inside a cell.Lysosomesare organelles that contain digestive enzymes. • Lysosomes destroy worn-out or damaged organelles, get rid of waste materials, and protect the cell from foreign invaders.

27. Section2 Eukaryotic Cells Chapter C1 Cellular Digestion, continued • Vacuolesare vesicles. • In plant and fungal cells, some vacuoles act like lysosomes. The large central vacuole in plant cells stores water and other liquids.

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29. Section3 The Organization of Living Things Chapter C1 Bellringer Why can’t you use your teeth to breathe? Why can’t you use your arm muscles to digest food? Write your answers in your science journal.

30. Section3 The Organization of Living Things Chapter C1 Objectives • Describe four levels of organization in living things. • Explain the relationship between the structure and function of a part of an organism.

31. Section3 The Organization of Living Things Chapter C1 Cells Working Together • Atissueis a group of cells that work together to perform a specific job. • Animals have four basic types of tissues: nerve tissues, muscle tissue, connective tissue, and protective tissue. • Plants have three types of tissues: transport tissue, protective tissue, and ground tissue.

32. Section3 The Organization of Living Things Chapter C1 Tissues Working Together • Astructure made up of two or more tissues working together to perform a specific function is called anorgan. • The heart, stomach, intestines, brain, and lungs are examples of organs in humans. • Leaves, stems, and roots are examples of plant organs.

33. Section3 The Organization of Living Things Chapter C1 Tissues Working Together, continued • A group of organs working together to perform a particular function is called anorgan system. Each organ system has a specific job in the body. • Examples of organ systems are the digestive system, the respiratory system, and the cardiovascular system. • Examples of plant organ systems are leaf systems, root systems, and stem systems.

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35. Section3 The Organization of Living Things Chapter C1 Overview of Organ Systems Click below to watch the Visual Concept. You may stop the video at any time by pressing the Esc key. Visual Concept

36. Section3 The Organization of Living Things Chapter C1 Structure and Function • Inorganisms, structure and function are related. • Structureis the arrangement of parts in an organism. • Functionis the job that the part does.

37. Section3 The Organization of Living Things Chapter C1 Structure and Function, continued • The structures of alveoli and blood vessels enable them to perform a function. Together, they bring oxygen into the body and get rid of its carbon dioxide.

38. Standardized Test Preparation Chapter C1 Reading Read each of the passages. Then, answer the questions that follow each passage.

39. Standardized Test Preparation Chapter C1 Passage 1Exploring caves can be dangerous but can also lead to interesting discoveries. For example, deep in the darkness of Cueva de Villa Luz, a cave in Mexico, are slippery formations called snottites. They were named snottites because they look just like a two-year-old’s runny nose. If you use an electron microscope to look at them, you see that snottites are prykaryotes; thick, sticky fluids; and small amounts of minerals produced by the prykaryotes. Continued on the next slide

40. Standardized Test Preparation Chapter C1 Passage 1, continuedAs tiny as they are, these prykaryotes can build up snottite structures that may eventually turn into rock. Formations in other caves look like hardened snottites. The prykaryotes in snottites are acidophiles. Acidophiles live in environments that are highly acidic. Snottite prykaryotes produce sulfuric acid and live in an environment that is similar to the inside of a car battery.

41. Standardized Test Preparation Chapter C1 1. Which statement best describes snottites? ASnottites are prykaryotes that live in car batteries. BSnottites are rock formations found in caves. CSnottites were named for a cave in Mexico. DSnottites are made of prykaryotes, sticky fluids, and minerals.

42. Standardized Test Preparation Chapter C1 1. Which statement best describes snottites? ASnottites are prykaryotesthat live in car batteries. BSnottites are rock formations found in caves. CSnottites were named for a cave in Mexico. DSnottites are made of prykaryotes, sticky fluids, and minerals.

43. Standardized Test Preparation Chapter C1 2. Based on this passage, which conclusion about snottites is most likely to be correct? FSnottites are found in caves everywhere. GSnottite prykaryotesdo not need sunlight. HYou could grow snottites in a greenhouse. ISnottites create other prykaryotesin caves.

44. Standardized Test Preparation Chapter C1 2. Based on this passage, which conclusion about snottites is most likely to be correct? FSnottites are found in caves everywhere. GSnottite prykaryotes do not need sunlight. HYou could grow snottites in a greenhouse. ISnottites create other prykaryotesin caves.

45. Standardized Test Preparation Chapter C1 3. What is the main idea of this passage? AAcidophiles are unusual organisms. BSnottites are strange formations. CExploring caves is dangerous. DSnottites are large, slippery prykaryotes.

46. Standardized Test Preparation Chapter C1 3. What is the main idea of this passage? AAcidophiles are unusual organisms. BSnottites are strange formations. CExploring caves is dangerous. DSnottites are large, slippery prykaryotes.

47. Standardized Test Preparation Chapter C1 Passage 2The world’s smallest mammal may be a bat about the size of a jelly bean. The scientific name for this tiny animal, which was unknown until 1974, is Craseonycteris thonglongyai. It is so small that it is sometimes called the bumblebee bat. Another name for this animal is the hog-nosed bat. Hog-nosed bats were given their name because one of their distinctive features is a piglike muzzle. Continued on the next slide

48. Standardized Test Preparation Chapter C1 Passage 2, continuedHog-nosed bats differ from other bats in another way: they do not have a tail. But, like other bats, hog-nosed bats do eat insects that they catch in mid-air. Scientists think that the bats eat small insects that live on the leaves at the tops of trees. Hog-nosed bats live deep in limestone caves and have been found in only one country, Thailand.

49. Standardized Test Preparation Chapter C1 1. According to the passage, which statement about hog-nosed bats is most accurate? AThey are the world’s smallest animal. BThey are about the size of a bumblebee. CThey eat leaves at the tops of trees. DThey live in hives near caves in Thailand.

50. Standardized Test Preparation Chapter C1 1. According to the passage, which statement about hog-nosed bats is most accurate? AThey are the world’s smallest animal. BThey are about the size of a bumblebee. CThey eat leaves at the tops of trees. DThey live in hives near caves in Thailand.