ESSENTIAL QUESTIONS
 How do genetic traits in populations and species change over several generations?
 What changes in genetic traits have occurred due to natural selection?
 What changes in genetic traits have occurred due to selective breeding?
 How does the survival of an organism depend on its adaptations to its environment?
 How do you use a dichotomous key to identify organisms based on their structural characteristics?
 How do the adaptations of the internal structures of organisms allow for specific functions?
 How do organisms respond to external and internal stimuli in order to maintain homeostasis?
 How do forces affect motion in living systems?
7.11 Organisms and environments. The student knows that populations and species demonstrate
variation and inherit many of their unique traits through gradual processes over many generations.
7.11C Including identify and describe:
Natural selection – changes in genetic traits over many generations
 Changes in genetic traits due to natural selection. (e.g.: claws and beaks of birds, counter-shading in
fish, evolution of the horse, etc.)
 Galapagos Medium Ground Finch traits (change in food sources – change in bill size)
Selective breeding – the breeding of parent organisms by man to produce desired traits in the next
generation
 Changes in genetic traits due to selective breeding. (e.g.: dog breeds, food crops, bees, livestock)
 Undesirable traits can sometimes appear when trying to produce desirable traits in selective breeding.
(e.g.: killer bees, hip dysplasia in dogs, white deaf Great Danes)
7.11B, 7.12A, 7.13A
 Adaptations – structural or behavioral features necessary for survival in different environments
 Includes animal and plant adaptations for movement, getting energy, responding to internal or external
stimuli, reproducing
 Relationships between variations among populations in the same community should be recognized.
Animal Adaptations – these are examples that may be investigated
 Appendages of animals have many varying functions
 Compare feet/beaks of different types of birds
 Gills in fish
 Hollow bones in birds
 Compare appendage adaptations for movement and/or feeding
 Endo and Exoskeletons
 Body coverings
 Scales, skin, feathers, hair
 Behavioral adaptations that enhance survival – responses to external stimuli 7.13A
 Mating behaviors
 Care of young
 Response to danger – hiding, fight or flight, etc
 Migration, hibernation, periods of dormancy
 Burrowing
Plant Adaptations
 How a species moves, obtains food, reproduces
 Plant Tropisms (e.g.: phototropism, geotropism, hydrotropism, thigmotropism)
 Plants make their own food through photosynthesis; autotrophs
 Plants reproduce sexually by seed production from flowers or cones or asexually by budding as with
potato plants
 Plant Structural Adaptations (e.g.: types of roots, xylem in plants, types of leaves, seed dispersal)
 Storage of food in a bulb so that the plant can use it to grow a new stem and leaves in Spring
 Plant Structural Adaptations (e.g.: types of roots, xylem in plants, types of leaves, seed dispersal)
 Storage of food in a bulb so that the plant can use it to grow a new stem and leaves in Spring
 Attracting pollinators through scent, color, structures for landing
7.11A
Examine structures of organisms in order to identify them using a dichotomous key
 Plant parts (roots, stems, leaves, flowers, seeds) are used to classify plants using dichotomous keys. Plant
examples: Trees
 Animal structures (appendages, beaks, etc.) are used to classify animals using dichotomous keys. Animal
examples: Insects, fish, birds
7.13B
 Responses to internal stimuli – describe and relate organism responses
o Availability of water and food - without adequate food or water, organisms will die
o Space - organisms require adequate space in order to receive enough resources;
o Temperature - organisms can only survive within specific ranges of temperatures (human pathogens,
Archaebacteria)
 Plant Responses
o Wilting from lack of water (review turgor pressure from cells unit)
o overcrowded conditions cause plants to become diseased and die
o Plants will freeze or dry out in extreme temperatures
o Increased growth and general health of a plant that is fertilized
 Animal Behavioral Responses to internal stimuli (homeostasis)
o Temperature – reptile sunning
o Hunger, thirst – feeding, drinking
o Immune response
7.7C
 Emergence of seedlings occurs during germination
 when the seed begins to absorb water into the seed tissues, building up pressure until the outer seed coat
bursts
o turgor pressure pushing on the seed coat
 when the seedling begins to grow and emerge from the soil
o geotropism (aka, gravitotropism) may be a positive response to gravity – root grows down and a negative
response to gravity – stem grows up
Vocabulary: to review: pre-assess for prior knowledge
adaptation
environment
flower
force
function
genetic
hibernation
inherit
leaves
migration
motion
organism
equilibrium
generation
population
roots
seed
species
stem
structure
survival
taxonomy
traits
turgor pressure
reproduction
internal structure
mutation
natural selection
phloem
phototropism physiology
response
selective breeding
stimulus
structural adaptation
variation
xylem
Vocabulary new for mastery
appendage
behavioral adaptation
dichotomous key
domestic animals
evolution
external stimulus
extinction
genes
geotropism
homeostasis
hydrotropism
internal stimulus