# Zoology Lecture 6

 What and how many kingdoms exist within the domain eukaryota 1. Protozoa2. Animalia3. Fungi4. Plantae5. Chromista What is the main difference between protozoa and vertebrets The fact that protozoa is dominated by an environment with high viscous forces Are there advantages to living ina world dominated by inertial forces? ANSER THIS he asked it What is the cost of living in a world with hgiher inertial forces takes more energy to do things What are the limits to size increase and complexity in protozoans What is the "issue of mass transfer"? Issue of mass transfer - movement of matter within a system What are two general forms of movment associated with a protists environment 1. Diffusion2. Bulk motion/convection Does diffusion (above) require energy for movement? No it does not. Diffusion is the free energy gradiant Does bulk motion/convection (above) require energy for motion? Yes energy input is required Do we generally see the above two processes together or acting alone? Both of these processes are interlocked and we will gnerally see one process of the two dominating the other. What is Ficks first law? Fick's first law relates the diffusive flux to the concentration field, by postulating that the flux goes from regions of high concentration to regions of low concentration, with a magnitude that is proportional to the concentration gradient (spatial derivative). Whats flux equal to? Flux = Ja = (-D) x (dC/dx)Where D is the diffusion constant What is a key restriction on cell size The diffusion of mRNA to various parts of the cell limits the size of which a cell can grow to Whats an example of overcoming the restrictions of smal cell size due to mRNA diffusion create more mRNA sources i.e create more nucleihence we end up with micro and macro nucleated cells Whats another solution to the limiting effects of cell size forma colony What are two types of colonies that can form (general) Spherical and plate like colonies can form How was ficks law used to describe or measure the size of a cell ficks law the difussion law looked at the diffusion of oxygen into a cell. cells need oxygen. so if the oxygen cant get far enough into the cell the cell will die. What are Metazoa Multicellular, obligatory heterotrophic eukaryotes How do metazoa first develop by mitotic divisions of a zygote formed by fusion of two angiogamates PORIFERA just saying What is ment genera;l;y by porifera Pore bearers/sponges Body symmetry ____________ and highly dependant on local _______ ________. 1. plastic2. ecological conditions. Multicellular but with a restricted number of ______, no true _____ and with low levels of _________ between cells. cell typestissuescoordination ___________ are characteristic and generate feeding currents. Choanocytes Define Choanocyte Choanocytes (also known as "collar cells") are cells that line the interior of Asconoid, syconoid and leuconoid body type sponges that contain a central flagellum surrounded by a collar of microvilli which are connected by a thin membraneThe flagellae beat regularly, creating a water flow across the microvilli which can then filter nutrients and other food from the water taken from the collar of the sponge. Food particles are then phagocytosed by the cell. Principal mode of food acquisition – _____________ filter/suspension feeding A large dependency on _________ for material exchange. diffusion A sometimes elaborate skeletal system of ________________ (spongin) fibresor a combination of these. calcareous or siliceous spiculesor collagen Adults are _____ but development usually involves a __________ larva. sessileplanktonic Reproduction: . ___________________ The latter may be gonochoristicbut more commonly __________. asexual or sexualhermaphroditic. Exclusively aquatic and overwhelmingly ______. - ----- WTF marine Should we consider a sponge as an organism or more so a colony of cells More so a colony of cells because a sponge is at the cellular grade See figure 4.5 for basic sponge morphology Define pinacoderm pinacoderm - is the outer most layer of cells (pinacocytes) in the phylum Porifera (sponges), equivalent to the epidermis in other organisms. Define the choanoderm Choanoderm - is composed of flagellated collar cells, or choanocytes. The sponge body is mostly a connective tissue, the mesohyl, over which are applied epithelioid monolayers of cells, the outer pinacoderm and the inner choanoderm. Define porocytes Porocytes are tubular cells which make up the pores of a sponge. Define osculum Osculum - a large opening in a sponge through which water flows out of the sponge. Sponges may have more than one oscula. Define Archeocytes Archaeocytes or amoebocytes are amoeboid cells found in sponges. They are totipotent and have varied functions depending on the species. Reside in mesophyll performing various functions What are scleroblasts Scleroblasts - a spicule secreting cell in porifera What is ment by rhabdiferous cells Rhabdiferous cells is the gelatenous stuff that makes up the mesophyll layer of sponges Do sponges have muscles? if so in what form Yes they do. Myocytes acting as sphyncters to entrances What can spicules be used for? Species identification See figure 4.5 for spicles and body forms :-) Done AuthorWill123 ID43419 Card SetZoology Lecture 6 DescriptionZoology Lecture 6 Updated2010-10-19T20:15:24Z Show Answers