Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Exchange with the Environment Bellwork Which of the following best describes a living cell: a) building block b) a living organism c) a complex factory d) all of the above Chapter 4

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Exchange with the Environment What Is Diffusion? Diffusion is the movement of particles from regions of higher to lower concentrations. Diffusion of Water The diffusion of water through cell membranes is called osmosis. Chapter 4

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Exchange with the Environment What Is Diffusion?, continued The Cell and Osmosis Osmosis is important to cell functions because mostly made of water. Plasma surrounds red blood cells and is made up of water, salts, sugars, and other particles. Osmosis keeps the concentration of these particles in balance. When a wilted plant is watered, osmosis makes the plant firm again. Chapter 4

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Exchange with the Environment Moving Small Particles Passive Transport The movement of particles across a cell membrane without the use of energy by the cell is called passive transport. Diffusion Active Transport A process of transporting particles that requires the cell to use energy is called active transport. Osmosis Chapter 4

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Exchange with the Environment Chapter 4

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Exchange with the Environment Moving Large Particles Endocytosis The active-transport process by which a cell surrounds a large particle and encloses & enters the particle in a vesicle to bring the particle into the cell is called endocytosis. Active transport Exocytosis The process in which a cell releases a particle by enclosing the particle in a vesicle that then moves to the cell surface and fuses with the cell membrane is called exocytosis. Active transport Chapter 4

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Exchange with the Environment Chapter 4

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Cell Energy Bellwork Make a list of all the different types of cells that you can think of and the jobs they do. Then make a list of all the reasons that a cell needs energy. Chapter 4

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Cell Energy From Sun to Cell Photosynthesis is the process by which plants, algae, and some bacteria use sunlight, carbon dioxide, and water to make food (glucose). Chlorophyll Plant cells have molecules that absorb light energy. These molecules are called pigments. Chlorophyll, the main pigment used in photosynthesis, gives plants their green color. Chapter 4

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Cell Energy From Sun to Cell, continued Chapter 4

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Cell Energy Spectrum of Light and Plant Pigments Chapter 4 Click below to watch the Visual Concept. You may stop the video at any time by pressing the Esc key. Visual Concept

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Cell Energy Getting Energy from Food Cellular Respiration During cellular respiration, food (such as glucose) is broken down into carbon dioxide and water, and energy is released. Chapter 4

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Cell Energy Getting Energy from Food, continued Connection Between Photosynthesis and Respiration During photosynthesis, cells take in carbon dioxide and release oxygen. During cellular respiration, cells use oxygen to break down glucose and release energy and carbon dioxide. Fermentation When muscles can’t get the oxygen for cellular respiration, they use fermentation to get energy. Fermentation is the breakdown of food without the use of oxygen. Produce lactic acid Chapter 4

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Cell Energy Chapter 4

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 The Cell Cycle Bellwork Biology is the only science in which multiplication means the same thing as division—at least with regards to cells. Chapter 4

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 The Cell Cycle The Life of a Cell Why make new cells? Replace dead cells The cell cycle begins when the cell is formed and ends when the cell divides and forms new cells. Before a cell divides, it must make a copy of its DNA which is organized into structures called chromosomes. Chapter 4

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 The Cell Cycle The Life of a Cell, continued Making More Prokaryotic Cells Cell division in bacteria is called binary fission, which means “splitting into two parts.” Bacteria have a single circular DNA molecule (chromosome). Binary fission results in two cells that each contain one copy of the circle of DNA. Chapter 4

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Copyright © by Holt, Rinehart and Winston. All rights reserved. Section 3 The Cell Cycle The Life of a Cell, continued Eukaryotic Cells and Their DNA The chromosomes of eukaryotic cells contain more DNA than those of prokaryotic cells. In a eukaryotic cell, chromosomes are found in the nucleus and are made of DNA and protein. Pairs of similar chromosomes are called homologous chromosomes. Chapter 4

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 The Cell Cycle The Life of a Cell, continued Making More Eukaryotic Cells The cell cycle has three stages: 1.Interphase: The cell grows and copies its chromosomes. The two copies are now called chromatids. 2.Mitosis: The chromatids separate. 3.The cell splits into two identical cells. Chapter 4

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 The Cell Cycle Mitosis and the Cell Cycle Mitosis has four phases: 1.prophase 2.metaphase 3.anaphase 4.telophase Chapter 4

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 The Cell Cycle Mitosis Chapter 4 Click below to watch the Visual Concept. You may stop the video at any time by pressing the Esc key. Visual Concept

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 The Cell Cycle Mitosis and the Cell Cycle, continued Cytokinesis is the division of cytoplasm. In animal cells and other eukaryotes that do not have cell walls, division of the cytoplasm begins at the cell membrane. In plant cells and in other eukaryotes with cell walls, a cell plate forms and the cell splits into two cells. Chapter 4

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 The Cell Cycle Chapter 4

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Interpreting Graphics The graph below shows the cell cycle. Use this graph to answer the questions that follow. Chapter 4 Standardized Test Preparation

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 1. Which part of the cell cycle lasts longest? A interphase B mitosis C cytokinesis D There is not enough information to determine the answer. Chapter 4 Standardized Test Preparation

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 1. Which part of the cell cycle lasts longest? A interphase B mitosis C cytokinesis D There is not enough information to determine the answer. Chapter 4 Standardized Test Preparation

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 2. Which of the following lists the parts of the cell cycle in the proper order? F mitosis, cytokinesis, mitosis G interphase, cytokinesis, mitosis H interphase, mitosis, interphase I mitosis, cytokinesis, interphase Chapter 4 Standardized Test Preparation

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 2. Which of the following lists the parts of the cell cycle in the proper order? F mitosis, cytokinesis, mitosis G interphase, cytokinesis, mitosis H interphase, mitosis, interphase I mitosis, cytokinesis, interphase Chapter 4 Standardized Test Preparation

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 3. Which part of mitosis is the briefest? A interphase B cell cycle C cytokinesis D There is not enough information to determine the answer. Chapter 4 Standardized Test Preparation

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 3. Which part of mitosis is the briefest? A interphase B cell cycle C cytokinesis D There is not enough information to determine the answer. Chapter 4 Standardized Test Preparation

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 4. Why is the cell cycle represented by a circle? F The cell cycle is a continuous process that begins again after it finishes. G The cell cycle happens only in cells that are round. H The cell cycle is a linear process. I The cell is in interphase for more than half of the cell cycle. Chapter 4 Standardized Test Preparation

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 4. Why is the cell cycle represented by a circle? F The cell cycle is a continuous process that begins again after it finishes. G The cell cycle happens only in cells that are round. H The cell cycle is a linear process. I The cell is in interphase for more than half of the cell cycle. Chapter 4 Standardized Test Preparation