Chapter 13 (Introduction to Animals)
Animal Characteristics
(1) Animals cannot make their own food
(2) Animals digest their food (components in food are used
by the body)
(3) Many animals move from place to place. Moving around
lets them find food, mates, a better place to live and
escape from predators
(4) Animals have many cells (unicellular or multicellular?)
(5) Animal cells are eukaryotic (a nucleus and organelles
surrounded by membranes)
Classification
Vertebrate or Invertebrate?
vertebrates - animals with backbones (97% of all aminals)
examples: fish, humans, birds and snakes
invertebrates - animals that don't have backbones
examples: sponges, jellyfish, worms, insects & clams
Symmetry
animal symmetry - arrangement of the animal's body parts
Radial Symmetry - Some animals have body parts arranged in a circle around a central point (the way spokes are arranged around the hub on a bicycle wheel).
example: jellyfish
Bilateral Symmetry - an animal which has its body parts arranged in the same way on both sides of its body (each half is a mirror image of the other)
example: butterfly & human
Asymmetrical - An organism that has no definite shape. There is no way their bodies can be divided into matching halves.
Review cell parts (animal & plants)
Identify cell components utilizing weblink (cellsalive)
Remember your research paper? It's due this Friday.
20 March 2002
Objective - distinquish between innate and learned behavior
Objective - recognize reflex and instinctive actions and explain how they help organism survive
Objective - describe and give examples of imprinting, trial and error, conditioning and insight
Behavior
-is the way an organism acts toward its environment
2 types
(#1) Innate Behavior
- a behavior that an organism is born with
Reflexes
- simplest of the innate behaviors
-- an automatic response that does not involve the brain
(Sneezing, shivering, yawning, jerking your hand away from a hot surface, and blinking your eyes when something is thrown toward you are all reflex actions. All animals have reflexes.)
Instinct
- a complex pattern of innate behavior
(Have you ever watched a spider spin a web? Spinning a web is complicated, and yet spiders spin webs correctly on the first try.)
(#2) Learned Behavior
- behavior that develops in an animal's lifetime (the result of experience or practice)
Why is learning important?
It allows animals to respond to new situations. In changing environments, animals that have the ability to learn new behavior are more likely to survive.
(Especially important for animals that have long lifespans because the longer an animal lives, the more likely it is that the environmentinwhich it lives will change.)
Imprinting
- a type of learning in which an animal forms a social attachment to another organism within a specific time period after birth or hatching
Trial & Error
- behavior that is modified by experience
(Can you remember when you learned to ride a bike? You probably fell a few times before you learned to balance.)
Conditioning
Insight
- a form of reasoning that enables animals to use past experiences to solve new problems.
Quiz - 21 Mar 02 What do you need to know?
distinquish between vertebrates and invertebrates
bilateral symmetry
2 types of behavior
know the animal characteristics
distinquish between reflex & instinct
distinquish between trial and error, imprinting & insight
21Mar02
Amphibians
what are they?
The word amphibian comes from the Greek word amphibios, which means "double life".
- ectothermic vertebrates that spend part of their lives in water and part on land
(ectotherm - vetebrate animal whose internal body
temperature changes with its environment)
How land and water?
Amphibians have moist skin that is smooth, thin, and without scales. Oxygen and carbon dioxide are exchanged through the skin and the lining of the mouth. Amphibians also have small, simple, saclike lungs in the chest cavity to use for breathing.
Ampibian Adaptations
Because amphibians are ectotherms, their body temperatures change when the temperature of their surroundings changes.
During cold winter months, they become inactive. (they bury themselves in mud or leaves until the temperature warms up. (hibernation)
Amphibians that live in hot, dry environmens have other adaptations. They become inactive and hide in the ground when temperatures become extreme. (estivation)
(Examples of amphibians are salamanders, toads and frogs)
Reptiles
What are they?
A reptile is an ectothermic vertebrate with dry, scaly skin.
(The class Reptilia includes lizards, snakes, turtles, crocodiles and alligators.)
Reptiles have many characteristics that are adaptations for life on land. A thick, dry, waterproof skin covered with scales prevents drying out and injury. With the exception of snakes, reptiles have four legs with claws that hold the body off the ground for moving quickly.
Reptiles breath with lungs.
Cell Division
Mitosis
- the process in which the nucleus divides to form two identical nuclei
5 step process
Interphase, Prophase, Metaphase, Anaphase, Telophase
Interphase (nucleus is clearly visible, chromosomes cannot be seen, but are actively duplicating themselves)
Prophase (Chromosomes become visible. Nucleus and nuclear membrane fade and disappear. 2 small structures called centrioles move to opposite ends of the cell. Between the centrioles, threadlike spindle fibers begin to stretch across the cell.)
Metaphase (The double stranded chromosome line up across the center of the cell.)
Anaphase (The double stranded chromosome separate and begin to move toward opposite ends of the cell.)
Telophase (Centrioles and spindle fibers start to disappear and become harder to see. 2 new nuclei appear.)
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