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What Is Biology?

• The study of living things.

Biologists Study?• Characteristics

• Classifications

• Interactions between

organisms

• Health & Disease

Goal of Science

• To investigate

• To understand

• To explain

• To make predictions

ABOUT the World!

Levels of Organization(Place in Order from Smallest to Largest)

Tissues Cells

Organs Atoms

Molecules Organ Systems

Levels Of Organization

• Atom

• Molecule

• Cells

• Tissues

• Organs

• Organ Systems

Levels of biological

organization

Largest

Smallest

Defining What It Means To Be Alive

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Characteristics of Living ThingsCharacteristics of Living Things

1.1. Made Up of CellsMade Up of Cells

2. Reproduction2. Reproduction

3. Based on a Genetic Code 3. Based on a Genetic Code

4. Growth and Development4. Growth and Development

5. Need for Materials and Energy5. Need for Materials and Energy

6.6. Response to the EnvironmentResponse to the Environment

7.7. Maintaining Internal BalanceMaintaining Internal Balance

8.8. Adapt & EvolveAdapt & Evolve

1. Living Things are made up of Cells.

� Cells are basic unit of life

� CELL: Collection of living material enclosed within a barrier

� Unicellular: made up of one cell

� Multicellular: made up of many cells

Unicellular

Multicellular

2. Living Things

Reproduce:

�produce offspring

which resemble parents

2 Types:

Asexual reproduction:

has only one parent

Sexual reproduction: requires two parents

Asexual

Sexual

3. Living Things are based on a

Genetic Code/Organization

�Inheritance of

traits is carried on DNA

From Dog To DNA…………1. A dog is made up of more than a million cells.

2. Each cell contains a nucleus containing chromosomes.

3. The cell’s

Nucleus

4. A Chromosome

5. DNA molecule folds to form a chromosome

6. DNA is made of 2

strands. 1 strand is a

gene

A Cell

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4. Living things Grow and Develop

� GROWTH: increase in size & shape

� DEVELOPMENT: mature over time

� Living things have a Lifespan

Growth

DevelopmentGrowth

5. Living Things Use

& Need Energy

Energy comes from food, used to maintain body

• AUTOTROPH: produce own food

• HETEROTROPH: must consume food

•DECOMPOSER: breaks

down dead material for food

6. Living things respond

to their surroundings

� React to a stimulus (a signal causing an

organism to respond)

� An action causes a reaction

called a response

Stimulus?

Response?

7. Living things maintain a stable

Internal Environment

� HOMEOSTASIS or DYNAMIC EQUILIBRIUM

Examples: sweating, panting, shivering, etc.

HomeostasisHow Does Your Body Bring You Back To Normal?

& Why?

�Perspiration

� Shivering

� Regurgitation

To stay cool & prevent overheating

To stay warm

Get rid of harmful waste

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Homeostasis

If you think about it, your body works the same way. Most people maintain a constant body temperature around 98.6 degrees. That is your homeostasis. When facing conditions such as heavy exercise or hot weather, your body has numerous mechanisms to keep your temperature at homeostasis. Sweat is produced from glands in the dermis. As the water in the sweat changes from liquid to gas (evaporation), heat is lost allowing you to feel cooler. Your face gets red and flushed. This is due to the dilation of blood vessels which brings heat to the surface of your skin where it is lost to the environment.

8. Living things Adapt & Evolve

� Adapt to changes in the environment

� Change to better survive

in environment

� Changes take place

over a long period of time & involve the entire

species

Adaptation� A Cactus with

horns

� A Camel’s Hump

� A Camel’s webbed feet, long eye lashes,

& nostrils that close

To reduce water loss & protect from herbivores

To store fat & live off it when food & water are scarce

Prevent sinking in the sand & prevent sand from entering eyes, nose

DO NOW: Write each sentence in your notebooks. Identify which

characteristic of life it is describing.

A. Adapt D. genetic code G. Respond to stimulus

B. Made of cells E. Grow and develop H. Homeostasis

C. Reproduce F. Use/need energy

1. You eat a hamburger for lunch.

2. A baby gains 3 pounds in one week and begins to recognize voices.

3. A polar bear has white fur to blend in with the snow.

4. You start to cry whenever you get a shot at the doctor’s office.

5. You begin to shiver because it is cold outside.

6. Red and white particles make up part of your blood.

7. A chick breaks out of an egg.

F.E.

A.

G.

H.

B.

C.

Life Processes: Terms1. Nutrition

– taking materials & changing to a usable form

(used for energy, growth, repair and maintenance)

� Digestion – large insoluble molecules changed into small

soluble molecule by enzymes.

� Ingestion – to consume (take in) a substance

2 Types

Autotrophs – make their own food

Heterotrophs – get their food

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• Photosynthesis for Energy

Equation:

CO2 + H2O Sugar + Oxygen + Water

Sunlight

2. Transport

– Substances enter and leave cells (movement of stuff within organism)

– A system in larger multicellular organism

Example: Circulatory System (arteries/veins)

3. Cellular Respiration for Energy

– Cells burn food (glucose) for fuel (chemical energy)

– Energy is stored in molecules called ATP

– All cells continuously undergo this process

called cellular respiration in the MITOCHONDRIA

Equation: Sugar + oxygen CO2 + H2O + Energy

2 Types

• Aerobic Respiration

organisms use O2 to break food to make

carbon dioxide & water.

• Anaerobic Respiration

No O2 used to break down food.

4. Synthesis– Simple substances are combined (built on) to

form more complex substances

(Needed for growth and repair)

5. Growth

- More cells & bigger cells

- Humans start as 1 cell & grow and develop into an organism of about 50 trillion cells.

Examples:

Unicellular- increase their cell size

Multicellular- go through growth called development

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6. Excretion

– Removal of wastes

4 Types of excretion:

urination

defecation

exhaling

sweating

7. Regulation

– Maintain homeostasis

– Regulation occurs by nerve impulses (nervous

system) & the release of chemical hormones (endocrine system)

– Needed to respond to the internal & external

environment

8. Reproduction

– Produce new organisms of their own

kind

Two types:

• Asexual – 1 parent with identical

offspring

• Sexual – 2 parents with offspring not

identical

9. Metabolism

• All the Chemical Reactions that occur in every cell to maintain normal functioning.

• The building & breaking down of complex substances.

• The continuous release of energy.

Virus

Virus Uses A Host’s Cell For Reproduction

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Is A Virus Living?

3 Essential Criteria for Aliveness� Growth � Metabolism

� Reproduction

Viruses Do Not Possess These Viruses Do Not Possess These

CharacteristicsCharacteristics

Is A Virus Living?

Viruses have……..

• No Growth

• No Metabolism

• No Reproduction (uses a host for

reproduction)

What Do You Think Now?

The End

http://hillgrovehighschool.typepad.com/maria_avitiafreeman/files/characteristics_of_life_u1_bio.ppt

Cellular RespirationGlucose(sugar) is used to produce high energy storage

molecules know as ATP.

Energy is stored in the bonds of the ATP molecule. This is

the energy source for all life processes.

Oxygen from the

environment.

Oxygen from the

environment.

MitochondriaMitochondria

GlucoseGlucose

Water

Carbon

Dioxide

Energy

(ATP)

Respiration occurs continuously in the cells of all organisms.

Photosynthesis

All animal life on Earth (including

humans) depends on the oxygen produced by photosynthesis!

Plants absorb carbon dioxide from

the air. Too much carbon dioxide

will cause the Earth to heat up(the greenhouse effect).

Animals can

eat the sugar made to use as

energy

chloroplastschloroplasts

Energy rich organic

compounds.

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DNA Replication

Nucleotides

floating free in the nucleus are

bonded to the

nucleotides on the original

strand.

A Way To Remember

• M

• R

• L

• S

• T

• R

• N

• G

• E

• R

How Will You Remember Them?

• A Song

• A Poem

• A Poster

• Flash Cards

• ???

http://www.slideshare.net/gmanb5/characteristics-of-life-113036/

• http://www.regentsreviewlive.net/rrl/powerpoint/2005/Biology_2005_TV.ppt