27 3 Annelids Review Bell Ringer 1 Review

27 -3 Annelids Review Bell Ringer 1. Review for vocabulary quiz (chapter 27, sections 1 & 2). 1 Slide of 36 End Show

27 -3 Annelids Slide of 36 Copyright Pearson Prentice Hall End Show

27 -3 Annelids What Is an Annelid? Annelids are worms with segmented bodies. They have a true coelom that is lined with tissue derived from mesoderm. Slide of 36 Copyright Pearson Prentice Hall End Show

27 -3 Annelids What Is an Annelid? Three Germ Layers of an Annelid Slide of 36 Copyright Pearson Prentice Hall End Show

27 -3 Annelids What Is an Annelid? The body of an annelid is divided into segments. Each segment is separated by septum, which are internal walls between each segment. Slide of 36 Copyright Pearson Prentice Hall End Show

27 -3 Annelids What Is an Annelid? Body segments may carry eyes, antennae, other sense organs, or be specialized for functions such as respiration. Bristles called setae may be attached to each segment Annelids have a tube-within-a-tube digestive tract that food passes through from the mouth to the anus. Slide of 36 Copyright Pearson Prentice Hall End Show

27 -3 Annelids Form and Function in Annelids have complex organ systems. Many of these systems are unique because of the segmented body plan of this group. Slide of 36 Copyright Pearson Prentice Hall End Show

27 -3 Annelids Form and Function in Annelids Feeding and Digestion In carnivorous species, the pharynx usually holds two or more sharp jaws that are used to attack prey. -Leeches Annelids that feed on decaying vegetation have a pharynx covered with sticky mucus. -Earthworms Slide of 36 Copyright Pearson Prentice Hall End Show

27 -3 Annelids Form and Function in Annelids In earthworms, the pharynx pumps food and soil into the esophagus. The food then moves through the crop, where it can be stored. It then moves through the gizzard, where it is ground into smaller pieces. Slide of 36 Copyright Pearson Prentice Hall End Show

27 -3 Annelids Form and Function in Annelids Circulation Annelids typically have a closed circulatory system, in which blood is contained within a network of blood vessels. Slide of 36 Copyright Pearson Prentice Hall End Show

27 -3 Annelids Form and Function in Annelids Respiration Aquatic annelids often breathe through gills. Land-dwelling annelids take in oxygen and give off carbon dioxide through their moist skin. Diffusion Slide of 36 Copyright Pearson Prentice Hall End Show

27 -3 Annelids Form and Function in Annelids Nephridia are excretory organs that filter fluid in the coelom. Nephridia Copyright Pearson Prentice Hall Slide of 36 End Show

27 -3 Annelids Form and Function in Annelids Response Most annelids have a well-developed nervous system consisting of a brain and several nerve cords. Brain Ganglia Copyright Pearson Prentice Hall Slide of 36 End Show

27 -3 Annelids Form and Function in Annelids Movement Annelids have two groups of body muscles that function as part of a hydrostatic skeleton. Longitudinal muscles Circular muscles Slide of 36 Copyright Pearson Prentice Hall End Show

27 -3 Annelids Form and Function in Annelids Reproduction Most annelids reproduce sexually. Earthworms are hermaphrodites. Two worms attach to each other, exchange sperm, and then store the sperm in special sacs. Slide of 36 Copyright Pearson Prentice Hall End Show

27 -3 Annelids Form and Function in Annelids A clitellum is a band of thickened, specialized segments. After eggs are fertilized in the ring, the ring slips off the worm's body and forms a protective cocoon. Young worms hatch weeks later. Slide of 36 Copyright Pearson Prentice Hall End Show

27 -3 Annelids Groups of Annelids are divided into three classes • oligochaetes • leeches • polychaetes Slide of 36 Copyright Pearson Prentice Hall End Show

27 -3 Annelids Groups of Annelids Oligochaetes contains earthworms and their relatives. Oligochaetes typically have streamlined bodies and relatively few setae compared to polychaetes. Most oligochaetes live in soil or fresh water. Slide of 36 Copyright Pearson Prentice Hall End Show

27 -3 Annelids Groups of Annelids Leeches The class Hirudinea contains the leeches. Leeches are typically external parasites that suck the blood and body fluids of their host. Slide of 36 Copyright Pearson Prentice Hall End Show

27 -3 Annelids Groups of Annelids Polychaetes are marine annelids that have paired, paddlelike appendages tipped with setae. The setae are brushlike structures on the worm. Slide of 36 Copyright Pearson Prentice Hall End Show

27 -3 Click to Launch: Continue to: - or - Slide of 36 End Show Copyright Pearson Prentice Hall

27 -3 In the earthworm, food is absorbed in an organ called the a. intestine. b. crop. c. gizzard. clitellum. Slide of 36 End Show Copyright Pearson Prentice Hall

27 -3 Annelids differ from other worm phyla because they have a. segmented bodies and a true coelom. b. unsegmented bodies and a pseudocoelom. c. mesoderm and one opening in the digestive system. d. segmented bodies and one opening in the digestive system. Slide of 36 End Show Copyright Pearson Prentice Hall

27 -3 How many major blood vessels does an earthworm have? a. one b. two c. three d. none Slide of 36 End Show Copyright Pearson Prentice Hall

27 -3 Ecologically, one of the most beneficial functions of an earthworm is to a. provide food for tropical fish. b. suck the blood of dead animals. c. aerate the soil. d. kill pest insects that inhabit the soil. Slide of 36 End Show Copyright Pearson Prentice Hall

27 -3 In an earthworm, the thickened bank of specialized segments is the a. nephridia. b. gizzard. clitellum. d. seta. Slide of 36 End Show Copyright Pearson Prentice Hall

27 -3 Annelids Practice Independent Practice 1. Complete section review sheet. 2. Complete pg. 699 1 -4 (write Q&A), and turn in. ***Remember, section 3 & 4 vocabulary quiz tomorrow. ***Wear appropriate clothes for dissection tomorrow. 27 Slide of 36 End Show