End Show 26-1 Introduction to the Animal Kingdom Slide 1 of 49 Copyright Pearson Prentice Hall What Is an Animal? Animals are multicellular, eukaryotic heterotrophs whose cells lack cell walls.

End Show 26-1 Introduction to the Animal Kingdom Slide 2 of 49 Copyright Pearson Prentice Hall What Is an Animal? Animals have the following types of tissues: epithelial muscular connective nervous

End Show 26-1 Introduction to the Animal Kingdom Slide 3 of 49 Copyright Pearson Prentice Hall What Is an Animal? Epithelial tissues cover body surfaces.

End Show 26-1 Introduction to the Animal Kingdom Slide 4 of 49 Copyright Pearson Prentice Hall What Is an Animal? Muscle tissue cells contain proteins that enable them to contract, moving parts of animals’ bodies.

End Show 26-1 Introduction to the Animal Kingdom Slide 5 of 49 Copyright Pearson Prentice Hall What Is an Animal? Connective tissues support an animal’s body and connect its parts.

End Show 26-1 Introduction to the Animal Kingdom Slide 6 of 49 Copyright Pearson Prentice Hall What Is an Animal? Nervous tissue contains nerve cells, which carry information throughout the body.

End Show 26-1 Introduction to the Animal Kingdom Slide 7 of 49 Copyright Pearson Prentice Hall What Is an Animal? Invertebrates make up 95% of all animal species. Invertebrates do not have a backbone, or vertebral column. They include sea stars, worms, jellyfishes, and insects.

End Show 26-1 Introduction to the Animal Kingdom Slide 8 of 49 Copyright Pearson Prentice Hall What Is an Animal? The other 5% of animals are vertebrates. Vertebrates have a backbone. Vertebrates include fishes, amphibians, reptiles, birds, and mammals.

End Show 26-1 Introduction to the Animal Kingdom Slide 9 of 49 Copyright Pearson Prentice Hall What Animals Do to Survive What essential functions do animals carry out?

End Show 26-1 Introduction to the Animal Kingdom Slide 10 of 49 Copyright Pearson Prentice Hall What Animals Do to Survive Animals carry out the following essential functions: feeding respiration circulation excretion response movement reproduction

End Show 26-1 Introduction to the Animal Kingdom Slide 11 of 49 Copyright Pearson Prentice Hall What Animals Do to Survive Many body functions help animals maintain homeostasis, or a relatively stable internal environment. Homeostasis is often maintained by internal feedback mechanisms called feedback loops. Most feedback loops involve feedback inhibition, in which the product or result of a process stops or limits the process.

End Show 26-1 Introduction to the Animal Kingdom Slide 12 of 49 Copyright Pearson Prentice Hall What Animals Do to Survive Feeding Herbivores eat plants.

End Show 26-1 Introduction to the Animal Kingdom Slide 13 of 49 Copyright Pearson Prentice Hall What Animals Do to Survive Feeding Carnivores eat other animals.

End Show 26-1 Introduction to the Animal Kingdom Slide 14 of 49 Copyright Pearson Prentice Hall What Animals Do to Survive Feeding Omnivores feed on both plants and animals.

End Show 26-1 Introduction to the Animal Kingdom Slide 15 of 49 Copyright Pearson Prentice Hall What Animals Do to Survive Feeding Detritivores feed on decaying plant and animal material.

End Show 26-1 Introduction to the Animal Kingdom Slide 16 of 49 Copyright Pearson Prentice Hall What Animals Do to Survive Feeding Filter feeders are aquatic animals that strain tiny floating organisms from water.

End Show 26-1 Introduction to the Animal Kingdom Slide 17 of 49 Copyright Pearson Prentice Hall What Animals Do to Survive Animals can also form symbiotic relationships, in which two species live in close association with each other.

End Show 26-1 Introduction to the Animal Kingdom Slide 18 of 49 Copyright Pearson Prentice Hall What Animals Do to Survive Respiration Whether they live in water or on land, all animals respire—they take in oxygen and give off carbon dioxide.

End Show 26-1 Introduction to the Animal Kingdom Slide 19 of 49 Copyright Pearson Prentice Hall What Animals Do to Survive Circulation Animals transport oxygen, nutrient molecules, and waste products among all their cells through either simple diffusion or some kind of circulatory system

End Show 26-1 Introduction to the Animal Kingdom Slide 20 of 49 Copyright Pearson Prentice Hall What Animals Do to Survive Excretion Ammonia is a waste product of cells and a poisonous substance. Most animals have an excretory system that eliminates ammonia quickly or converts it into a less toxic substance that is removed from the body.

End Show 26-1 Introduction to the Animal Kingdom Slide 21 of 49 Copyright Pearson Prentice Hall What Animals Do to Survive Response Animals respond to events in their environment using specialized cells, called nerve cells. In most animals, nerve cells form a nervous system. Receptor cells respond to sound, light, and external stimuli. Other nerve cells process information and determine how the animal responds.

End Show 26-1 Introduction to the Animal Kingdom Slide 22 of 49 Copyright Pearson Prentice Hall What Animals Do to Survive Movement Some animals stay at a single spot, but most can move. Most animals have muscles or musclelike tissues. Muscle contraction enables motile animals to move around by working in combination with a support structure called a skeleton. Muscles also help even sedentary animals feed and pump water and fluids through their bodies.

End Show 26-1 Introduction to the Animal Kingdom Slide 23 of 49 Copyright Pearson Prentice Hall What Animals Do to Survive Reproduction Most animals reproduce sexually. This helps to create and maintain genetic diversity in populations and improve species’ abilities to evolve when the environment changes. Many invertebrates can also reproduce asexually. This produces offspring that are genetically identical to the parent. It allows animals to increase their numbers rapidly.

End Show 26-1 Introduction to the Animal Kingdom Slide 24 of 49 Copyright Pearson Prentice Hall Trends in Animal Evolution Complex animals tend to have: high levels of cell specialization and internal body organization bilateral body symmetry a front end or head with sense organs a body cavity

End Show 26-1 Introduction to the Animal Kingdom Slide 25 of 49 Copyright Pearson Prentice Hall Trends in Animal Evolution Cell Specialization and Levels of Organization As animals have evolved, their cells have become specialized to carry out different functions. In multicellular organisms, each cell type has a structure and chemical composition that enable it to perform a specialized function.

End Show 26-1 Introduction to the Animal Kingdom Slide 26 of 49 Copyright Pearson Prentice Hall Trends in Animal Evolution Groups of specialized cells form tissues. Tissues join together to form organs and organ systems—all of which work together to carry out a variety of complex functions.

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