What is Biology?What is Biology?

Biology is The Study Biology is The Study of of Life.Life.

““BiosBios” - Life” - Life

““LogosLogos” - Study” - Study

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What do Biologists What do Biologists Study?Study?

The workings of The workings of the body the body systems.systems.

The interactions between The interactions between living organisms & with living organisms & with the the environment.environment.

They study problems and They study problems and propose propose solutionssolutions (i.e. (i.e. medical treatment, medical treatment, disease prevention etc)disease prevention etc)

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Why should we study Why should we study biology?biology?

1. Understand and appreciate the natural world.2. Understand developments in medicine, nutrition, and science.3. Understand environmental issues (water, air, soil, global warming).4. Understand human genome issues(stem cell research, gene therapy).

Gene TherapyGene Therapy

New biological techniquesNew biological techniques

What are What are stem cells stem cells ?? Unspecialized cells capable of renewing themselves Unspecialized cells capable of renewing themselves

through cell division & can be induced to become through cell division & can be induced to become tissue- or organ-specific cells tissue- or organ-specific cells

What is What is gene therapy gene therapy ?? Involves inserting a healthy & normal gene into a Involves inserting a healthy & normal gene into a

person’s cells to replace a gene that is abnormal and person’s cells to replace a gene that is abnormal and thus, produces disease.thus, produces disease.

When is it Life?When is it Life?

And when is it And when is it

Non-Life?Non-Life?

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This canyon is full of life because of the many This canyon is full of life because of the many species of animals living among the ferns and species of animals living among the ferns and plantsplants

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Am I a living organism ?Am I a living organism ?

Characteristics of Living Characteristics of Living organismsorganisms

1.1. NutritionNutrition

2.2. Sensitivity Sensitivity

((ability to adjust to ability to adjust to environment)environment)

3.3. RespirationRespiration

4.4. ExcretionExcretion

5.5. ReproductionReproduction

6.6. GrowthGrowth

7.7. MovementMovement

NutritionNutrition

Taking in of nutrients Taking in of nutrients necessary for energy necessary for energy production, growth and production, growth and tissue repair.tissue repair.

How do plants obtain nutrition?How do plants obtain nutrition?

1.1. Absorb Absorb water and water and mineral salts mineral salts from the from the soil through their roots.soil through their roots.

2.2. Plants can make their own Plants can make their own food through food through photosynthesisphotosynthesis..

Sensitivity/ Sensitivity/ IrritabilityIrritability

Ability to detect or Ability to detect or sense changes in the sense changes in the environment (environment (stimulistimuli) ) & to make & to make responses.responses.

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How do plants respond to their How do plants respond to their environment ? environment ?

They respond to They respond to sunlight and sunlight and temperature temperature changeschanges..

Plants move their Plants move their leaves to face the leaves to face the light.light.

Flowers of some plants Flowers of some plants open in the morning open in the morning and close at night.and close at night.

RespirationRespiration Chemical reactions that Chemical reactions that

combine oxygen with combine oxygen with glucose in living cells to glucose in living cells to produce energy.produce energy.

Do plants also respire?Do plants also respire?

ExcretionExcretion Removal of :Removal of :

1.1. toxic materialstoxic materials

2.2. waste products of waste products of metabolism &metabolism &

from an organism.from an organism.

3.3. substances in excess of substances in excess of requirements requirements

by the kidneys.by the kidneys.

How do plants perform How do plants perform excretion?excretion?

How do plants perform excretion?How do plants perform excretion?

Plants store waste Plants store waste substances in substances in their leaves, so their leaves, so the waste the waste chemicals are chemicals are removed when removed when leaves fall off.leaves fall off.

ReproductionReproduction

Processes that make Processes that make more of the same more of the same kind of organism.kind of organism.

Two types of Two types of reproduction:reproduction:

1.1. AsexualAsexual

2.2. SexualSexual

GrowthGrowth

A permanent A permanent increase in size & increase in size & dry mass of an dry mass of an organism.organism.

Caused by:Caused by:

1.1. Increase in cell Increase in cell numbernumber

2.2. Cell sizeCell size

3.3. Both of themBoth of them

MovementMovement

An action by an organism An action by an organism causing a change of causing a change of position or place.position or place.

Animals move their entire Animals move their entire bodies; plants move in bodies; plants move in response to external response to external stimuli.stimuli.

Who are we? Who are we?

We need We need nutrients/nutritionnutrients/nutrition for for energy, growth & tissue repairenergy, growth & tissue repair

We need to We need to detect and respond detect and respond to to changes in the environmentchanges in the environment

We need We need energy (obtained from energy (obtained from respiration)respiration)

We need to We need to excreteexcrete toxic materials and toxic materials and waste productswaste products

We need to We need to reproducereproduce We need to We need to growgrow and develop and develop We need to We need to move move aboutabout