 Short tubes extending outwards from cell membrane ◦ Like short hairs covering single cells

 Made of “microtubules” or “filaments” ◦ Like small, hollow straws or thin fibers ◦ Can produce great amounts of force ◦ Require the use of energy to move ◦ 80 – 100 nm (nm = billionth of a meter)  i.e., very small compared to other organelles  Present in all types eukaryotic cells ◦ Most cells don’t have cilia ◦ Can be present in some animals, plants fungi; more common in animals

 In general, use cilia to move cell or move objects along side the cell  Demo: hold up your arms!  Cilia are useful for a variety of tasks ◦ Help single-celled organisms move through water or other liquids ◦ Help some aquatic organisms filter feed  move water/food into mouths, into feeding cells, etc. ◦ Moving mucus up respiratory tract in vertebrates ◦ Move water along gills in many aquatic organisms ◦ Communication between cells, possibly

 Cilia can be like the legs of a millipede ◦ All work together to help the insect move  Or, cilia can be like moveable arm hairs ◦ Could control movement of air, fluids next to skin  Or, cilia can be like simple antennae ◦ Useful for basic communication?

 Without cilia: ◦ Many single-celled organisms couldn’t move! ◦ You’d drown in your own mucus!  (cilia move mucus out of your lungs) ◦ Aquatic organisms’ gills wouldn’t work! ◦ Filter-feeders might starve! ◦ Cells couldn’t communicate! What could be worse than immovable, drowning-in-mucus, silent cells that can’t breathe? Keep the cilia!

 Primary Ciliary Dyskinesia (PCD) ◦ Uncommon disease in which cilia lining trachea and lungs malfunction ◦ Can cause  Chronic, recurring infections in lungs, sinuses, ears  Infertility (cilia-like flagella in sperm don’t work)  Swelling in brain  Organ displacement

 List main points here – summarize  Then take questions

 Cover ALL requirements in 3-5 min ◦ Less than 3 min, probably incomplete  More than one slide per requirement - ok  Bullets with BRIEF INFO!  OK to use color, pictures, backgrounds, fonts to enhance slides ◦ Don’t overdo it. ◦ Keep format consistent  May use notes during your presentation  Practice eye contact, voice, difficult words

 It is very, very important that, while you have plenty of information in your slides, your writing is not so lengthy and wordy (containing run-on sentences, for example), that students are so busy reading it they forget to listen to you and miss everything you’re saying so your slide becomes not helpful and distracting. Oh, and please don’t read from the screen word for word.  Instead, try brief bullets ◦ Containing information that you explain

 Make sure it’s easy to read!  Make text at least 24 font  Animations are ok, but please don’t have too many or a lot of different types  Keep font size similar

Thanks!