Animal & Plant Cells Noadswood Science, 2012

Animal & Plant Cells  To know the structure of animal and plant cells, and the function of each part Sunday, May 03, 2015

Cells  A cell is the basic building block for both animals and plants  Cells are extremely small (we need a microscope to see them)  Animal cells have some basic properties (although this is a basic generalisation - we can get extremely specialised cells)  You need to learn the parts which make up our animal cell… Specialised cells e.g. gametes Animal cells - stained

Animal Cell  Draw an animal cell, labeling each of the key parts and identifying their function

Animal Cell Animal cells contain: -  Cell membrane  Cytoplasm  Nucleus  Mitochondria  Ribosomes Cell membrane Nucleus Cytoplasm Mitochondria Ribosomes (small bodies on the endoplasmic reticulum)

Functions  You must also know the functions of the parts which make up the animal cell PartFunction NucleusContains genetic material, which controls the activities of the cell CytoplasmMost chemical processes take place here, controlled by enzymes Cell membraneControls the movement of substances into and out of the cell MitochondriaMost energy is released by respiration here RibosomesProtein synthesis happens here (attached to the endoplasmic reticulum)

Plant Cell  Draw a plant cell, labeling each of the key parts and identifying their function

Plant Cell Plant cells contain: -  Cell membrane  Cytoplasm  Nucleus  Mitochondria  Ribosomes  Cell Wall  Vacuole  Chloroplasts Cell membrane Nucleus Cytoplasm Cell wall Vacuole Chloroplast Mitochondria Ribosomes

Functions PartFunction NucleusControls what happens in the cell (but it is not a ‘brain’)! Cell MembraneControls what substances can enter and exit the cell CytoplasmWhere chemical reactions take place (jelly-like substance) MitochondriaMost of the cells energy is released here via respiration RibosomesProtein synthesis occurs here Chloroplasts (Plants only) Where photosynthesis occurs (contain chlorophyll (which is green)) Vacuole (Plants only) Contains cell sap (a solution of sugar and salt) helping with rigidity Cell wall (Plants only) Made of cellulose, which gives support to the cell

Microscopes Practical  Using the microscopes prepare and view a slide of your cheek cells: -  Swipe a cotton bud on the inside of your cheek and smear onto a slide  Add a drop of methylene blue (stain)  Lower the cover slip  Place the cotton bud into the disinfectant  Draw your slide and label it, including its magnification

Microscopes There is a procedure of 8 steps you need to follow to use a microscope correctly… 1.Place the smallest objective lens (the smallest lens) over the hole in the stage 2.Turn the coarse focusing wheel to make the gap between the stage and the objective lens as small as possible 3.Place a slide on the stage, and secure with the clips. The slide contains what you want to see (your specimen)

Microscopes 4.Adjust the light source so light goes up through the stage 5.Look into the eyepiece lens 6.Turn the coarse focusing wheel slowing, until your specimen is in focus

Microscopes 7.To see your specimen in more detail, turn the next largest objective lens over your specimen 8.Use the fine focusing wheel to get your image into focus again - do not use the coarse focusing wheel - this can break your slide!

Magnification  Magnification is easy to work out - it is the eyepiece lens x the objective lens: Magnification = magnification eyepiece lens x magnification objective lens E.g. eyepiece lens = 10x objective lens = 60x Magnification = 10 x 60 = 600x magnification

Cell Size  All living things are made of cells but you cannot see them with the naked eye so scientists use microscopes to magnify the image  The largest cell in the human body is the ova (egg cell) which measures approximately 0.1mm (smaller than a full stop)  The smallest cell is the sperm measuring 0.06mm in length from head to tail and the width of the head is just mm

Measurements  The average animal cells is 0.02mm across whilst the average plant cell is 0.04mm across  Conversion of units: -  Millimeters (mm) = 1m x10 -3  Microsmeters (μm) = 1m x10 -6  Nanometers (nm) = 1m x10 -9  Cell surface membranes are mm thick – work out what this is this in micrometes and nanometers… 0.01μm or 10nm