chapter 3 adapting to the environment preview section 1 animal reproductionanimal reproduction...
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Chapter 3 Adapting to the Environment
Preview
Section 1 Animal Reproduction
Section 2 Plant Reproduction
Section 3 Animal Behavior
Section 4 Adaptations and Survival
Concept Mapping
Chapter 3 Section 1 Animal Reproduction
Bellringer
Do you know how birds, ants, humans, and sea stars reproduce? Write down any difference that you are aware of in how these animals reproduce. Also, write down any differences that you know of in how these animals raise their young.
Write your answers in your science journal.
Chapter 3
Objectives
• Describe the patterns and advantages of asexual reproduction in animals.
• Describe the patterns and advantages of sexual reproduction in animals.
• Explain how sexual reproduction is related to variation within a species.
Section 1 Animal Reproduction
Chapter 3
Objectives, continued
• Explain the difference between external and internal fertilization.
• Identify the three different types of mammalian reproduction.
Section 1 Animal Reproduction
Chapter 3
Asexual Reproduction
• In asexual reproduction, a single parent has offspring that are genetically identical to the parent.
• Budding, fragmentation, and regeneration are all ways in which a parent organism can produce genetically identical offspring.
Section 1 Animal Reproduction
Chapter 3
• In sexual reproduction, offspring are formed when genetic information from more than one parent combines.
• Sexual reproduction in animals usually requires two parents—a male and a female.
• The female parent produces sex cells called eggs. The male parent produces sex cells called sperm.
Sexual Reproduction
Section 1 Animal Reproduction
Chapter 3
Sexual Reproduction, continued
Section 1 Animal Reproduction
Chapter 3
• External Fertilization is the process when the sperm fertilizes the eggs outside the female’s body.
• Internal Fertilization is the process when the egg and sperm join inside the female’s body.
Internal and External Fertilization
Section 1 Animal Reproduction
Chapter 3
• Monotremes are mammals that lay eggs.
• Marsupials are mammals that give birth to partially developed live young. Most marsupials have pouches where their young continue to develop after birth.
• Placental Mammals are nourished inside their mother’s body before birth.
Mammals
Section 1 Animal Reproduction
Chapter 3 Section 2 Plant Reproduction
Bellringer
Brainstorm a list of ways that plants disperse theirseeds.
Write your answers in your science journal.
Chapter 3
Objectives
• Describe the pattern of sexual reproduction in nonvascular plants.
• Describe the pattern of sexual reproduction in seedless vascular plants.
• Describe the pattern of sexual reproduction in seed plants.
• Identify three kinds of asexual reproduction in plants.
Section 2 Plant Reproduction
Chapter 3
Reproduction in Nonvascular Plants
• Nonvascular plants must be covered by a film of water in order for fertilization to occur.
• Eggs and sperm form in separate structures, which are often on separate plants.
• When water covers the clumps of gametophytes, sperm swim to the female gametophytes and fertilize the eggs.
Section 2 Plant Reproduction
Chapter 3
Reproduction in Seedless Vascular Plants
• Similar to nonvascular plants, seedless vascular plants can only reproduce when a film of water covers the gametophyte.
• However, in most species of seedless vascular plants, both eggs and sperm are produced on the same plant.
• Gametophytes of seedless vascular plants are usually very small and develop on or below the surface of soil.
Section 2 Plant Reproduction
Chapter 3
Reproduction in Seed Plants
• Reproduction in Gymnosperms Most gymnosperms have reproductive structures called cones.
• Wind transfers pollen from the male cone to the female cone during pollination.
• Sperm from pollen fertilize the eggs of the female cone.
Section 2 Plant Reproduction
Chapter 3
Reproduction in Seed Plants, continued
• Reproduction in Angiosperms In angiosperms, gametophytes develop within flowers.
• Pollination happens when pollen is moved from anthers to stigmas.
• Fertilization happens when a sperm fuses with the egg inside an ovule.
Section 2 Plant Reproduction
Chapter 3
Reproduction in Seed Plants, continued
Section 2 Plant Reproduction
Chapter 3
Reproduction in Seed Plants, continued
• From Flower to a Fruit After fertilization takes place, the ovule develops into a seed. The seed contains a tiny, undeveloped plant.
• As a fruit swells and ripens, it protects the developing seeds.
• Fruits often help a plant spread its seeds.
Section 2 Plant Reproduction
Chapter 3
Reproduction in Seed Plants, continued
• From Seed to a Plant When seeds are dropped or planted in a suitable environment, the seeds sprout and young plants begin to grow.
• To sprout, most seeds need water, air, and warm temperatures.
• Each plant species has an ideal temperature at which most of its seeds will begin to grow.
Section 2 Plant Reproduction
Chapter 3
Reproduction in Seed Plants, continued
Section 2 Plant Reproduction
Chapter 3
Reproduction in Seed Plants, continued
Other methods of reproduction include:
1. Plantlets Tiny plants grow along the edges of a plant’s leaves. These plantlets fall off and grow on their own.
2. Tubers Underground stems, or tubers, can produce new plants after a dormant season.
3. Runners Above-ground stems from which new plants can grow are called runners.
Section 2 Plant Reproduction
Chapter 3 Section 3 Animal Behavior
Bellringer
Write a sentence to describe each of the following terms: predator, prey.
List three animals that are predators and three thatare prey. Are humans predators or prey? Explainyour answer.
Write your answers in your science journal.
Chapter 3
Objectives
• Explain the difference between learned and innate behavior.
• Describe five kinds of behaviors that help animals survive.
• Identify seasonal behaviors that help animals adapt to the environment.
Section 3 Animal Behavior
Chapter 3
Kinds of Behavior
• Innate Behavior Behavior that doesn’t depend on learning or experience is known as innate behavior. Innate behaviors are inherited through genes.
• Learned Behavior Innate behaviors can be modified. Animals can use learning to change a behavior. Learned behavior is behavior that has been learned from experience or from observing other animals.
Section 3 Animal Behavior
Chapter 3
• Finding Food Animals find food in many ways. Animals that eat other animals are known as predators. The animal being eaten is the prey.
• Marking Territory Some animals claim territories to save energy by avoiding this competition.
• A territory is an area that is occupied by one animal or by a group of animals that do not allow other members of the species to enter.
Survival Behavior
Section 3 Animal Behavior
Chapter 3
• Defensive Action Defensive behavior allows animals to protect resources from other animals. Animals defend food, mates, and offspring.
• Courtship Animals need to find mates to reproduce. Reproduction is essential for the survival of an individual’s genes. Animals have special behaviors, called courtship, that help them find a mate.
• Parenting Many young animals depend on their parents for survival.
Survival Behavior, continued
Section 3 Animal Behavior
Chapter 3
• Migration Many animals avoid cold weather by traveling to warmer places. These animals migrate to find food, water, or safe nesting grounds.
• Hibernation is a period of inactivity and decreased body temperature that some animals experience in winter.
• Many animals experience a internal slowdown in the hottest part of the summer during a period called estivation.
Seasonal Behavior
Section 3 Animal Behavior
Chapter 3
• A Biological Clock The internal control of an animal’s natural cycles is called a biological clock. Animals use clues such as the length of the day and the temperature to set their clocks.
• Cycles of Change Some biological clocks control long cycles. Seasonal cycles are nearly universal for animals.
Seasonal Behavior, continued
Section 3 Animal Behavior
Chapter 3 Section 4 Adaptation and Survival
Bellringer
In your own words, write a definition for thefollowing terms: adaptation, natural selection, andcompetition.
Write your definitions in your science journal.
Chapter 3
Objectives
• Identify three kinds of adaptations that help organisms survive.
• Describe the four parts of natural selection.
• Explain Explain how variation occurs within a population.
Section 4 Adaptation and Survival
Chapter 3
Objectives, continued
• Explain why genetic variation within a population is important.
• Explain how resistance to insecticide is a survival characteristic.
Section 4 Adaptation and Survival
Chapter 3
Adaptations for Obtaining Food
• An adaptation is a characteristic that improves an individual’s ability to survive and reproduce in a particular environment.
• Almost all organisms have adaptations to help them obtain food.
Section 4 Adaptation and Survival
Chapter 3
Predator-Prey Adaptations
• Many organisms also have adaptations that serve as a defense against predators.
• One common adaptation that helps predators and prey is called camouflage. An organism that is camouflaged is disguised so that it is hard to see even when the organism is in view.
Section 4 Adaptation and Survival
Chapter 3
Adaptations to Interactions
• Two species can also acquire adaptations because of their interaction with one another.
• Adaptations because of interactions can take place between any organisms that live close together.
Section 4 Adaptation and Survival
Chapter 3
Natural Selection
• Inherited characteristics in populations can change over time.
• Natural selection is the process by which individuals that are better adapted to their environment survive and reproduce more successfully than less well-adapted individuals do.
Section 4 Adaptation and Survival
Chapter 3
• The theory of natural selection explains how a population changes in response to its environment.
• If natural selection is always taking place, a population will tend to be well adapted to its environment.
• The individuals that are likely to survive and reproduce are those that are best adapted at the time.
Natural Selection, continued
Section 4 Adaptation and Survival
Chapter 3
Natural Selection, continued
Section 4 Adaptation and Survival
Chapter 3
Changes in Genetic Variation
• In order for natural selection to continue, individuals within the population must be different.
• Over time, the population will be made up of more individuals with characteristics that help them survive.
• If a population decreases rapidly, a genetic bottleneck occurs. Many characteristics may be lost entirely from a population because all of the individuals with those characteristics died.
Section 4 Adaptation and Survival
Chapter 3 Section 4 Adaptation and Survival
Chapter 3
Insecticide Resistance
• Insecticide resistance is also a result of natural selection.
• Some individual insects within a population are resistant to certain insecticides. Resistance is an adaptation.
• These insects survive and reproduce. They pass the insecticide-resistance genes to their offspring.
Section 4 Adaptation and Survival
Chapter 3 Adapting to the Environment
Use the terms below to complete the concept map on the next slide.
asexual reproduction buddingexternal fertilization fragmentationreproduction internal fertilizationsexual reproduction
Concept Mapping
Chapter 3 Adapting to the Environment
Chapter 3 Adapting to the Environment