bio chap1 (1)

1.1 The Study of Life

KEY CONCEPTScience is a way of thinking, questioning, and gathering evidence.


Like all science, biology is a process of inquiry.

• Scientists make careful and systematic observations.

• Scientists test their hypotheses and analyze their data.

• Scientists form a hypothesis as a possible answer to a question.

• Scientists record observations as data.


Observation

• Observational studies allow scientists to describe a phenomenon.

• Use of senses • Use of instruments or tools• Study of previous data


• It must be testable.• It uses inductive reasoning from a set of specific

observations to reach a general conclusion.• It uses deductive reasoning from general premises to the

specific.

Hypothesis


• Experiments and further observations allow scientists to determine what causes a phenomenon.

• Designing a controlled experiment.• Control group vs experimental group.

Biologists use experiments and observations to test hypotheses.


– Independent variables are manipulated –” the cause”

Constants are conditions that are kept the same which are necessary for determining whether the independent variable produces any change in the dependent variable.

– Dependent variables are observed and measured – “the effects”


• Quantitative Data• Qualitative Data• Present data in forms of graph or table• Statistical Analysis• Conclusion based on the analysis of data• Report findings in journals and scientific conferences• Experiments and observations must be repeatable

Analysis of Data and Conclusion


A theory explains a wide range of observations.

• Theories explain a wide range of observations and experimental results.

• A theory is supported by a wide range of scientific observations, experiments and data.

• Theories can change based on new evidence.


KEY CONCEPT Biology is the study of all forms of life.


Earth is home to an incredible diversity of life.

• The biosphere includes all living things and all the places they are found.

biosphere = everywhere life exists


Earth is home to an incredible diversity of life.

• Every part of the biosphere is connected with every other part.

• The biosphere includes many environments.– land environments


• The biosphere includes many environments.

– saltwater and freshwater environments

– portions of the atmosphere

Tidepool Estuary


– Biodiversity generally increases from the poles to the equator.

– Biodiversity is greater in areas with consistently warm temperatures.

• Biodiversity is the variety of life.

Biodiversity is greater closer to the equator.


All organisms share certain characteristics.

• Biology is the scientific study of all forms of life.


• An organism is any individual living thing.

– All are made of one or more cells.


– All need energy for metabolism.

• An organism is any individual living thing.

– All are made of one or more cells.

– All respond to their environment (stimuli).– All have DNA that they pass on to offspring (reproduce).– All adapt to their environment.– All are capable of locomotion or movement.– All are capable of growth

Intussusception- growth from within

Accretion – “growth” from the outside by non-living things


1.How do we know that a three-foot tall Irish wolfhound and a six-inch-high chihuahua are the same species?

2.At what point would the two breeds become separate species?


Evolution explains the unity and diversity of life.

• Evolution is the change in living things over time.– The genetic makeup of a population of a species

changes.– Evolution can occur through natural selection of

adaptations.– Adaptations are beneficial inherited traits that are

passed to future generations.


• Evolution accounts for both the diversity and the unity of life.


Organisms must maintain homeostasis to survive in diverse environments.

• Homeostasis is the maintenance of constant internal conditions.


KEY CONCEPTUnderstanding biology can help you make informed decisions.


– cancer

• Knowledge of biology helps you understand your health.

– effects of alcohol, tobacco, and other drugs

brain

lungs

heart

liver

kidneys

– food allergies

– potential effects of obesity


• Knowledge of biology can help you understand environmental issues.– interactions in ecosystems

– biodiversity– pollution


Biotechnology offers great promise but also raises many issues.

• Biotechnology is the use and application of living things and biological processes.


1. What trait or characteristic do these animals have in common?2. What do you think was manipulated or changed in their cells that gave these animals their new trait?

Green fluorescent protein (GFP) in jellyfish transformed them to glow.Ex. It is used to tag genes of certain diseases to study their cure; tag cells to study their pathways.


GENETIC ENGINEERING

The process of changing an organism’s DNA to give it new traits.

New genes can be added to an organism’s DNA to produce a transgenic organism.

A transgenic organism has one or more genes from another organism inserted into its genome.

Give applications of transgenic organisms.


• Questions are raised about the use of biotechnology.

– spread of undesirable genes– decrease in biodiversity– ethical considerations

– safety of genetically modified crops


– DNA testing in medicine and forensics

• Biotechnology is the use and application of living things and biological processes.


• There are still many questions to answer in biology.

– How are memories stored in the brain?


• There are still many questions to answer in biology.

– How are memories stored in the brain?

surface proteins

lipid

envelope

nucleic acid capsid

– Does life exist on planets other than Earth?

– How do viruses mutate?

bio chap1 (1)

Technology