Chapter 7 Lesson 1 Page 168 - 193

Life is cellular

The Cell Theory

1.       The cell theory is a fundamental concept of biology.

2.       The Cell theory states:

·         All living things are composed of cells.

·         Cells are the basic units of structure and function in living things.

·         New cells are produced from existing cells.

3.       The nucleus is a large membrane—enclosed structure that contains the cell’s genetic material in the form of DNA.

4.       Eukaryotes are cells that contain nuclei.

5.       Prokaryotes are cells that do not contain nuclei.

6.       Prokaryotes cells have genetic material that is not combined in a nucleus.

7.       Eukaryotic cells contain a nucleus in which their genetic material is separated from the rest of the cell.

8.       Many of these structures act as if they are specialized organs; these structures are known as organelles, literally little organs.

Chapter 7 Lesson 2

9.       The Cytoplasm is the portion of the cell outside the nucleus.

10.   The nucleus contains nearly all the cell’s DNA and with it the coded instructions for making proteins and other important molecules.

11.   The nucleus is surrounded by a nuclear envelope composed of two membranes.

12.   The granular material you can see in the nucleus is called chromatin.

13.   When a cell divides, however chromatin condenses to form chromosomes.

14.   Most nuclei also contain a small, dense region known as the nucleolus.

15.   Proteins are assembled on ribosomes.

16.   Ribosomes are small particles of RNA and protein found throughout the cytoplasm.

17.   Eukaryotic cells also contain an internal membrane system known as the endoplasmic reticulum.

18.   The endoplasmic reticulum is the site where lipid components of the cell membrane are assembled, along with proteins and other materials that are exported from the cell.

19.   Protein produced in the rough ER move next into an organelle called the Golgi apparatus, discovered by the Italian scientist Camillo Golgi.

20.   The function of the Golgi apparatus is to modify, sort, and package proteins and other materials from the endoplasmic reticulum for storage in the cell or secretion outside the cell.

21.   Lysosomes are small organelles filled with enzymes.

22.   Some kinds of cells contain saclike structures called vacuoles.

23.   Nearly all eukaryotic cells including plants contain mitochondria singular mitochondrion.

24.   Mitochondria are organelles that convert the chemical energy stored in food into compounds that are more convenient for the cell to use.

25.   Plants and some other organisms contain chloroplasts.

26.   Chloroplasts are organelles that capture the energy from sunlight and convert it into chemical energy in a process called photosynthesis.

27.   Eukaryotic cells have a structure—the cytoskeleton—that helps supports the cell.

28.   The cytoskeleton is a network of protein filaments that helps the cell to maintain its shape. The cytoskeleton is also involved in movement.

29.   Centrioles are located near the nucleus and help to organize cell division.

Chapter 7 lesson 3

30.   All cells are surrounded by a thin flexible barrier known as the cell membrane.

31.   Many cells also produce a strong supporting layer around the membrane known as a cell wall.

32.   The main function of the cell wall is to provide support and protection for the cell.

33.   The concentration of a solution is the mass of solute in a given volume of solution, or mass/volume.

34.   As a result, the particles tend to move from an area where they are more concentrated a process known as diffusion.

35.   When the concentration of the solute is the same throughout a system, the system has reached equilibrium.

36.   Because diffusion depends upon random particle movements, substance diffuses across membrane without requiring the cell to use energy.

37.   An important process known as osmosis is the result.

38.   Osmosis is the diffusion of water through a selective permeable membrane.

39.   When this happens the two solutions will be isotonic, which means same strength.

40.   When the experiment began, the more concentrated sugar solution was hypertonic, which means above strength as compared to the dilute sugar solution.

41.   The dilute sugar solution was hypotonic, or below strength.

42.   This cell membrane protein is said to facilitate, or help the diffusion of glucose across the membrane. The process shown in figure 7-17 is known as facilitated diffusion.

43.   Active Transport energy-requiring process that moves material across a cell membrane against a concentration difference.

44.   Endocytosis is the process of taking material into the cell by means of infoldings or pockets of the cell membrane.

45.   In phagocytosis extensions of cytoplasm surround a particle and package it within a food vacuole.

46.   Tiny pockets form along the cell membrane fill with liquid and pinch off to form vacuoles within the cell. This process is known as pinocytosis.

47.    During exocytosis the membrane of the vacuole surrounding the material fuses with the cell membrane, forcing the contents out of the cell.

Chapter 7 Lesson 4

48.   Cells through-out an organism can develop in different ways to perform different tasks.

49.   Cell specialization separate roles for each type of cell in multicellular organisms.

50.   The levels of organization in a multicellular organism are individual cells, tissues, organs and organ systems.

51.   A tissue is a group of similar cells that perform a particular function.

52.   Organ group of tissues that work together to perform closely related functions.

53.   Organ system group of organs that work together to perform a specific function.