Cells and How They Alive

Cells Alive! Objectives: Understand the relative sizes of objects, including the cell, sketch and identify the function of cell structures; compare eukaryote to prokaryote cells; compare plant and animals’ cells Part A: "HOW BIG IS A...." Click on the How Big? link on the left side of the webpage. Instructions: Look at the objects that can be found on the head of a pin. Zoom in and out to determine which object is the smallest, then slowly zoom out so you can see how other objects compare. 1. 2. 3. If you zoom all the way in, what is the smallest object on the head of the pin? Rhinovirus Zoom out a little farther, what is the hook shaped object you see? Ebola Virus Compare each of the following objects on the pin, circle the one that is larger for each pair. a) baker's yeast or e coli b) lymphocyte or ragweed c) red blood cell or staphylococcus d) ragweed or dust mite Part B – Bacteria Cell Model Click on the Cell Models link on the left side of the webpage. Locate the image of a bacterial cell model and label the image below. Flagella Genophore Plasma Membrane Ribosomes Pili/filmbriae Capsule Cell Membrane Part C – Animal Cell Model Locate the image of the animal cell model and click through each of the parts and read their descriptions. Use the information to answer the questions and make sketches of the cell organelles. 1. What do mitochondria do? Generate most of the chemical energy needed to power the cell's biochemical reactions. Sketch each of the following. Mitochondria 2. How big are mitochondria? 0.5 to 3 µm 3. What does the Golgi Apparatus do? Organelle that helps process and package proteins and lipid molecules, especially proteins destined to be exported from the cell. 4. What is the difference between smooth and rough ER? RER is more structurally stable, but SER are less structurally stable. 5. Where is the nucleolus found? Within the cell nucleus. Golgi Apparatus 6. What does the nucleolus do? Ribosomal RNA (rRNA) synthesis and ribosome biogenesis. 7. What is inside the nucleus that is responsible for providing the cell with its characteristics? The cell 's DNA. Rough ER 8. What is the function of the lysosome? Break down excess or worn-out cell parts. Lysosome Part D – Plant Cell Model Locate the image of the plant cell model and click through each of the parts and read their descriptions. Use the information to answer the questions. 1. What structure takes up most of the center space within the plant cell? Central Vacuole. 2. What is its primary function of the structure? To protect and provide structural support to the cell. 3. What part of the plant cell gives it is green color? Chloroplast How many of these structures are visible in the plant diagram? 4 4. Fill in: Name the organelle or organelles that perform each of the following functions. a. Chloroplasts convert sunlight to chemical energy. b. The Cell Wall and the Central Vacuole help to support the plant cell and help it to maintain its shape. c. Chloroplast store food or pigments. d. The Mitochondria converts food into energy. It is found in both plant cells and animal cells. 5. Label the plant cell diagram RER (Rough endoplasmic recticulum Cell Membrane Nucleus Mitochondria Cytoplasm SER (Smooth endoplasmic recticulum Cell Wall Golgi apparatus Chloroplast Lysosome Ribosome Vacuole Part E – Plant vs. Animal Cell Compare/contrast the plant and animal cell by filling in the following graphic organizer. Use the characteristics listed in the table below. Write the appropriate characteristics in the correct section of graphic organizer. Please “bullet” the characteristics so they are easily distinguishable. Nucleus Chloroplast Cell Membrane Cell Wall Mitochondria Ribosomes DNA Can perform photosynthesis Can NOT photosynthesize More circular in shape Large central vacuole Can perform cellular respiration Animal Cell Cytoplasm Eukaryotic cells More square/rectangular in shape Plant Cell They are both alike because they both contain: A Nucleus, Cell Membrane, Cytoplasm, Mitochondria, Ribosomes, DNA, Eukaryotic cells, and Can perform cellular respiration. Animal cells are different because first they cannot photosynthesize. As well they have a more circular shape than plant cells. Plant cells are different because they can do things that animal cells can’t like they have Chloroplast, Cell Wall, Large central vacuole, can perform photosynthesis, and are more square/rectangular in shape. Part F - Comparing Cells Use what you know about each type of cell (reference pictures if needed), and place a check in the box if the cell has that characteristic or structure. Bacteria Cell Wall Cell Membrane Animal * * * * * * * Nucleus Cytosol Plant * Central Vacuole * * * Chloroplast * Mitochondria * * Part G – Cells Reading (Annotate concepts.) the text. Remember to circle and define unknown words and underline important On our planet Earth, life comes in a variety of forms. We have identified about 2 million species of animals (such as elephants), 270,000 types of plants (such as sunflowers), 5,000 kinds of bacteria (such E. coli), 80,000 different protists (such as algae), and 72,000 assorted fungi (such as mushrooms). What do all these organisms or living things have in common? They are made of the same thing - the cell. Some like animals and plants consist of many or even billions of cells, while others, like protists and bacteria, are unicellular. Robert Hooke was the first scientist to solve this great mystery of life. When he observed a thin slice of cork under a microscope in 1663, he noted that the cork looked like hundreds of tiny boxes or a honeycomb. Hooke called these tiny boxes "cells", which means "little rooms" in Latin. What Hooke did not realize at the time is that he was actually looking at the walls or outer layers of cells, not inside cells themselves. Nearly two hundred years had elapsed before any scientist made any new, significant break-through. The hard work put in by several scientists of the 19th century derived the Cell Theory: • All living things are made of • one or more cells. cells. Cells are the basic units of life. • All cells come from existing Today, we know that a thin sheet, called a cell membrane, separates one cell from another. We also know that there are two types of cells: prokaryotic cells and eukaryotic cells. Two important factors set these two groups of cells apart. The first is the existence of a nucleus, and the second is an organelle surrounded by a membrane. A nucleus is a special membranecovered organelle inside a cell where the cell's DNA or genetic material resides, and an organelle is a structure inside a cell that enables the cell to grow, live, and reproduce. Some organelles have membranes around them, but others do not. A prokaryotic cell has neither a nucleus nor any membrane-covered organelle. In other words, its DNA and organelles have no individual membranes surrounding them. Of all the living things, only bacteria are prokaryotic cells. A eukaryotic cell, on the contrary, has a nucleus to protect its DNA. Furthermore, all the organelles inside a eukaryotic cell are enclosed by their own membranes. Animals, plants, protists, and fungi are eukaryotic cells.