Cell Membrane Responsible for controlling what substances go into and out of the cell Think of a screen door…
How does stuff get in and out? The cell membrane is selectively permeable – some substances can pass through while others cannot 2 Types of Transport 1. Passive Transport – no energy required 2. Active Transport – energy required
Passive Transport Movement of material through the cell membrane without using energy Diffusion – the process by which molecules tend to move from an area of high concentration to an area of low concentration Osmosis – diffusion of water molecules through a selectively permeable membrane
Active Transport Movement of materials through a cell membrane using energy Transport Proteins – “pick up” molecules and pass them through the membrane Engulfing (Endocytosis) – cell membrane folds around a particle, creating a vacuole
Nucleus The cell’s control center, directing all of the cell’s activities Cells duplicate themselves through a process called… Mitosis – a cell’s nucleus divides into 2 nuclei and a copy of DNA is distributed into each daughter cell (cell division)
Cell Cycle 1. Interphase 2a. Mitosis: Prophase Mitosis: Metaphase 2c. Mitosis: Anaphase 2d. Mitosis: Telophase 3. Cytokinesis 2b. Cell grows, makes a copy of its DNA, and prepares to divide.
Cell Cycle 2a. Mitosis: Prophase Mitosis: Metaphase 2c. Mitosis: Anaphase 2d. Mitosis: Telophase 3. Cytokinesis 2b. 1. Interphase Chromosomes line up in the middle of cell. The chromatids separate and move to opposite ends of the cell. New nuclear membranes form. Chromatin condenses to form chromosomes, spindle fibers form, and the nuclear membrane breaks down.
Cell Cycle 2a. Mitosis: Prophase Mitosis: Metaphase 2c. Mitosis: Anaphase 2d. Mitosis: Telophase 3. Cytokinesis 2b. 1. Interphase The cell membrane pinches in around the middle of the cell, and the cell divides.
Inside the Cell Cytoplasm – clear, thick, gel-like fluid between the cell membrane and the nucleus Many organelles are found in the cytoplasm
Cell Organelles What is an organelle? “A tiny cell structure that carries out a specific function within the cell” Organelles are responsible for: 1. Producing Energy 2. Building and Transporting needed Materials 3. Storing and Recycling Wastes
Cell Organelles Mitochondria – “powerhouse” of the cell Produces energy for the cell Different types of cells have more/less Muscle Cells have large numbers of these Endoplasmic Reticulum – carry proteins and other materials from one part of the cell to another Cell Transport System Think of a network of “roads”
Cell Organelles Ribosomes – structure that makes proteins Some are free floating, some attached to E.R. Construction Workers – connect one amino acid to another to build long chains Golgi Bodies – receives proteins and other newly formed materials from the E.R., packages them, and sends them off to other parts of the cell for use Like a Post Office – packages and labels items that it sends off to different parts of the cell Also creates Lysosomes…
Cell Organelles Vacuoles – storage area for the cell Some animal cells do not have these Storage Area – Water, Food, Waste Lysosomes – break down large food particles into smaller ones Free-floating in the cytoplasm, they go to work when the cell absorbs or “eats” food. Also can break down old cell parts and release substances so they can be used again Garbage Collectors/Recyclers