Week 14 Lecture Notes Biology 3020
Week 14 Lecture Notes Biology 3020 BIOL 3020-001
Popular in Comparative Anatomy of the Vertebrates
verified elite notetaker
Popular in Biology
This 4 page Class Notes was uploaded by Maria Martinez on Tuesday November 24, 2015. The Class Notes belongs to BIOL 3020-001 at Middle Tennessee State University taught by Dr. Miller in Fall 2015. Since its upload, it has received 29 views. For similar materials see Comparative Anatomy of the Vertebrates in Biology at Middle Tennessee State University.
Reviews for Week 14 Lecture Notes Biology 3020
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 11/24/15
Week 14 Lecture Notes Biology 3020 Copulatorv Organs 0 J awless Fish Lamprey and Hagfish 0 Practice external fertilization o Amphibians o Frogs I Most practice external fertilization I Practice amplexus a type of mating behavior in which a male grasps a female with his front legs as part of the mating process and at the same he fertilizes the female eggs as they are released from the body I When they eggs have been fertilized they will be coated in a jelly like substance I Few frogs practice internal fertilization 0 Those that do use the cloacal kiss 0 Female and male press their cloacae together the male ejaculates and sperm is pushed into the cloaca when they detach it makes a kiss sound I Tailfrog o Practices oviparous don t retain the eggs inside of the body 0 Do not actually have a tail it is an extension from the cloaca 0 Practice internal fertilization is the only frog that does this 0 The males have a modified cloaca that protrudes from the cloaca to directly insert the sperm in the female s cloaca and is accid when not in use and engorges with blood when used 0 Salamanders I Few groups practice external fertilization I Most practice internal fertilization I None have intermittent organ but those who do have live births and have spermatophores o A pyramidal capsule or mass enclosing spermatozoa that is extruded by the male and is transferred to the reproductive tract of the female I Females have crisps in their cloaca that store the sperm which can last from days to weeks to years I Most are oviparous o Caecilians limbless aquatics I Practice internal fertilization I Have a phallus that develops and protrudes from the cloacal wall in males I Uses hydrostatic pressure to stiffen the phallus I The sperm ows through a sulcus spermaticus a groove on the surface of the penis that carries sperm 0 Amniotes o All practice internal fertilization 0 Some practice the cloacal kiss others have cloacal wall modifications and others have a penis though the type is variable between groups 0 Reptiles I Tuatara o The only reptiles without a penis they use the cloacal kiss I Crocodilians and Turtles 0 All oviparous 0 Have a true penis that develops embryonically from the cloaca and resides there when not in use 0 Requires hydrostatic pressure to enlarge and enter the female 0 Have a sulcus spermaticus I Squamates Lizards and Snakes 0 Have a phallus hemipenes o Hemipenes are paired copulatory organs developed form the cloacal wall 0 They are saclike structures that are everted from the cloaca 0 Can have spikes to help attach to the female 0 Require lymphatic system and blood for erection 0 Can be oviparous ovoviviparous and viviparous 0 Live birth has evolved greatly in these animals 0 Birds I Are oviparous I Most have internal fertilization by cloacal kiss I Some have a true penis with a sulcus spermaticus 0 True penis found in ightless birds like the ostrich and the emu 0 Do not have a urethra o Rely on hydrodynamics and lymphatics for erection o Mammals I All have internal fertilization I Monotremes 0 Platypus and the Echidna 0 Have a true penis that develops embryonically form the cloacal wall 0 The penis only carries sperm not urine 0 Practice oviparity I Marsupials Kangaroos and Opossum 0 Have a true bifurcated glans penis 0 Carry both urine and sperm 0 Have live birth but the connection between the mother and the embryo is slight so the young are underdeveloped 0 Have evolved to have rapid ovulation I Placental mammals Egg Development 0 Surinam Toad Have a true penis with a urethra Relies on a hydrostatic system of blood to engorge the penis 0 Corpus Spongiosum erectile tissues that holds blood during an erection and functions to protect the urethra 0 Corpus Cavernosa erectile tissues that holds some blood during an erection and prevent the urethra from pinching closed maintaining the urethra as a viable channel for ejaculation All use internal fertilization which happens high up in the body cavity Because ovaries are not covered by the oviduct an ectopic pregnancy a pregnancy that does not occur in the uterus or a uterine structure could happen The testosterone affects the female in embryo causing her clitoris to elongate and extend protruding from the body This is referred to as a pseudopenis The vaginal canal of a female hyena is housed inside the clitoris so to give birth the young have to travel to the long tube often suffocating and tearing the organ This makes mating difficult I The male frog climbs on the back of the female and they do ips in the water I The female will express a few eggs at a time and the male then catches the eggs with his body fertilizes them and rolls them into the holes in her back I The female s skin grows over the holes protecting the developing offspring for the four months of pregnancy I When the eggs are ready to hatch the babies begin to punch their hands through the holes until they are able to make their way through the female s skin The emerging offspring aren t the tadpoles that might be expected they actually come out as toadlets who will no longer need any help from their mother 0 Australian Frog Following external fertilization by the male the female would take the eggs or embryos which live entirely off yolk during their development into her mouth and swallow them During the tadpole development the mother does not eat and her lungs de ated and breathing relied more upon gas exchange through the skin The birth process consisted of the female essentially vomiting out the young frogs Is going extinct o Seahorses The female inserts her ovipositor into the male s brood pouch a front facing side of the tail and deposits dozens to thousands of eggs During this time seawater entered the pouch where the spermatozoa and eggs meet This hyperosmotic environment facilitates sperm activation and motility The fertilization is therefore regarded as being physiologically external within a physically internal environment after the closure of the pouch The young receive nourishment from egg yolks and are released from the male seahorse when ready
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'