1. Figure 1.3 Some properties of life.
Order
Response to
the environment
Evolutionary adaptation
Reproduction
Figure 1.3 Some properties of life.
Regulation
Energy processing
Growth and
development

2. The biosphere Tissues Ecosystems Organs and organ systems Communities
Figure 1.4 Exploring: Levels of Biological Organization
Cells
Organelles
Organisms
Atoms
Molecules
Populations

3. Cycling of chemical nutrients
Sunlight
Leaves absorb light energy from the sun.
Leaves take in carbon dioxide from the air and release oxygen.
CO2 O2
Cycling of chemical nutrients
Figure 1.5 Interactions of an African acacia tree with other organisms and the physical environment.
Animals eat
leaves and fruit
from the tree.
Leaves fall to the ground and are decomposed by organisms that return minerals to the soil.
Water and minerals in the soil are taken up by the tree through its roots.

4. Figure 1.6 Energy flow in an ecosystem.
Sunlight
Heat
When energy is used to do work, some energy is converted to thermal energy, which is lost as heat.
Producers absorb light energy and transform it into chemical energy.
An animal’s muscle cells convert chemical energy from food to kinetic energy, the energy of motion.
Chemical
energy
A plant’s cells use chemical energy to do work such as growing new leaves.
Chemical energy in food is transferred from plants to consumers.
Figure 1.6 Energy flow in an ecosystem.
(a) Energy flow from sunlight to producers to consumers
(b) Using energy to do work

5. (a) Wings (b) Wing bones
Figure 1.7 Form fits function in a gull’s wing.
(b) Wing bones

6. Nucleus (membrane- enclosed)
Prokaryotic cell
Eukaryotic cell
DNA
(no nucleus)
Membrane
Membrane
Cytoplasm
Figure 1.8 Contrasting eukaryotic and prokaryotic cells in size and complexity.
Nucleus (membrane- enclosed)
Membrane- enclosed organelles
DNA (throughout nucleus)
1 m

7. Fertilized egg with DNA from both parents
Sperm cell
Nuclei containing
DNA
Fertilized egg with DNA from both parents
Embryo’s cells with copies of inherited DNA
Egg cell
Figure 1.10 Inherited DNA directs development of an organism.
Offspring with traits inherited from both parents

8. (b) Single strand of DNA
Nucleus A C
DNA
Nucleotide T A T T
Cell A C C G T
Figure 1.11 DNA: The genetic material. A G T A
(a) DNA double helix
(b) Single strand of DNA

9. Figure 1.13 Regulation by feedback mechanisms.
Negative feedback
Enzyme 1 B D
Enzyme 2
Excess D blocks a step. D D C C
Enzyme 3 D
(a) Negative feedback W
Enzyme 4
Figure 1.13 Regulation by feedback mechanisms. X
Positive feedback 
Enzyme 5
Excess Z stimulates a step. Z Y Z Z
Enzyme 6 Z
(b) Positive feedback

10. Ursus americanus (American black bear)
Species
Genus
Family
Order
Class
Phylum
Kingdom
Domain
Ursus americanus (American black bear)
Ursus
Ursidae
Carnivora
Mammalia
Figure 1.14 Classifying life.
Chordata
Animalia
Eukarya

11. (a) Domain Bacteria (b) Domain Archaea (c) Domain Eukarya 2 m 2 m
Kingdom Animalia
100 m
Figure 1.15 The three domains of life.
Kingdom Plantae
Protists
Kingdom Fungi

12. 15 m 5 m 0.1 m Cilia of Paramecium Cilia of windpipe cells
Figure 1.16 An example of unity underlying the diversity of life: the architecture of cilia in eukaryotes.
0.1 m
Cross section of a cilium, as viewed with an electron microscope

13. Population with varied inherited traits 2 1
Population with varied inherited traits 2
Elimination of individuals with certain traits 3
Reproduction of survivors 4
Increasing frequency of traits that enhance survival and reproductive success
Figure 1.20 Natural selection.

14. Cactus-flower- eaters
Green warbler finch Certhidea olivacea
Warbler finches
Insect-eaters
COMMON ANCESTOR
Gray warbler finch Certhidea fusca
Sharp-beaked ground finch Geospiza difficilis
Seed-eater
Vegetarian finch Platyspiza crassirostris
Bud-eater
Mangrove finch Cactospiza heliobates
Woodpecker finch Cactospiza pallida
Tree finches
Insect-eaters
Medium tree finch Camarhynchus pauper
Large tree finch Camarhynchus psittacula
Small tree finch Camarhynchus parvulus
Large cactus ground finch Geospiza conirostris
Figure 1.22 Descent with modification: adaptive radiation of finches on the Galápagos Islands.
Cactus-flower- eaters
Cactus ground finch Geospiza scandens
Ground finches
Seed-eaters
Small ground finch Geospiza fuliginosa
Medium ground finch Geospiza fortis
Large ground finch Geospiza magnirostris

15. Figure 1.24 A campground example of hypothesis-based inquiry.
Observations
Question
Hypothesis #1:
Dead batteries
Hypothesis #2:
Burnt-out bulb
Prediction:
Replacing batteries will fix problem
Prediction:
Replacing bulb will fix problem
Figure 1.24 A campground example of hypothesis-based inquiry.
Test of prediction
Test of prediction
Test falsifies hypothesis
Test does not falsify hypothesis