Welcome to Biology 103 !

Instructor: Jerry Fugate

Office: 218B Jackson Hall

Biology 103 - Main points/Questions

1. Things to understand the first day.

2. What are we talking about this term?

3. What do you remember from 101 & 102?

4. Do all organisms reproduce like humans?

What do you remember from 101 (102?)?

Emergent property

• Can you remember what this term means

and an example from biology?

Terminology:

• Emergent property

– A property of a complex system that appears as

a result of interactions between the components

of the system.

Fig. 1.2, p. 4

These tiles all have properties – shape, texture, color, size, strength…

Emergent Properties:• Biological examples are common:

– Starch and Cellulose

Cellulose – an indigestible fiber that builds plant cell walls

Starch – an easily digested energy storage molecule.

Starch grains in a plant chloroplast

Emergent Properties:

• Biology is full of emergent properties

because there are many layers of

complexity – the hierarchy of biology!

More from 101&102

• Emergent property ✔

• Biological Hierarchy - what do we mean

by this?

This term we will focus on the intermediate levels of organization

•Tissues

•Organs

•Organ systems

• & Organisms

We will using humans as a starting point

Some Human Organ Systems

Each one has emergent properties!

Each organ system has an important role in building the organism that you are!

We will focus on reproduction first – but not just in humans.

Compare & Contrast

• Think of three or four ways plants and

animals are similar

• Think of three or four ways plants and

animals are different

• Gas exchange

• Circulation

• Nutrition

• Support...

• How do organisms build the properties they

need?

Plants have many of the same needs as animals

We build more and more complex assemblies… so do plants!

Plants have complex organization including

Tissues

Organs

Organ systems

More from 101 & 102

• Emergent property✔

• Biological Hierarchy✔

• Natural Selection – what do you

remember about how this works?

Relatively constant resourcesand population size over time

Potential forrapid reproduction

Competition for survivaland reproduction

Variability instructures and behaviors

NATURAL SELECTION:On the average, the fittest

organisms leave the most offspring

Some variabilityis inherited

EVOLUTION:The genetic makeup of the population

changes over time,driven by natural selection

Observation

Conclusion based on observation

• Your name.

• What was your favorite part of biology so far (where did you take it?)

• Thing you are most interested about in this class.

• Why are you taking this class (prereq? general requirement…? Major..?)

On scratch paper write:

• We sort organisms according to apparent similarities – homologies

• Domains are the broadest categories

Bacteria, Archaea & Eukarya

• Kingdoms are the next broadest

Bacteria, Archaea, Protista, Plantae, Fungi, Animalia

Organizing life into categories

More from 101 & 102

• Emergent property✔

• Biological Hierarchy✔

• Natural Selection✔

• Domain & Kingdom

• Three domains – do you remember them?– Bacteria - diverse prokaryotes – Archea - little studied prokaryotes, many

live in extreme environments.– Eukarya - cells with nucleus and

mitochondria• Animals• Plants• Fungi• Others... (protista)

Modern classification scheme

eukaryotic cell!prokaryotic cell!

• This term focus on the Eukarya (kingdoms?)– Animals– Plants– Fungi– Others... (protista)

• We focus mostly on organisms with complex multicellularity…

Modern classification scheme

Complex Multicellularity• cell specialization

– different cells use different genes– different genes are activated during development

• intercellular coordination – the adjustment of a cell’s activity in response to what

other cells are doing– the cells of all complex multicellular organisms

communicate with one another

• Plants & Animals (and many fungi) are like this

How do these organisms get the energy and materials (molecules) they need?

• Where do they get their energy?

– Chemo vs. photo

• Where do they get their nutrients?

– Hetero vs. auto

Different kingdoms are distinguished by…

• Modes of nutrition

– Plants – photosynthesis = photoautotrophs

– Fungi – absorptive chemoheterotrophs

– Animals – ingestive chemoheterotrophs

Often people will just say autotroph or heterotroph.

Different kingdoms are distinguished by…

• Reproductive strategy

• The kingdoms have different strategies for sexual reproduction

• All alternate meiosis & fertilization

– what do those terms mean?

Life Cycle Terminology:

• Haploid v. Diploid

• Meiosis

• Mitosis

• Fertilization

• Gametes

• Lets look at the animal life cycle…

Fig. 10.4

Specialized reproductive

cells (gametes) are haploid.

But they are made from diploid cells –

the process that does this is called

meiosis

Fig. 10.4

Haploid gametes then join together

This is called Fertilization & it produces a new

organism that is a genetic mix of both

parents!

Animal sexual reproduction:

• The main stage is a multicellular diploid organism

• Meiosis produces haploid gametes

• Fertilization immediately follows meiosis

Six criteria, together, create definition.

(1) Animals are multicellular eukaryotes.

(2) Animals are chemoheterotrophic

– They must take in preformed organic molecules through ingestion, eating other organisms or organic material that is decomposing.

What is an animal?

(3) Animal cells lack cell walls

– The bodies of animals are held together with extracellular proteins, especially collagen.

– Other structural proteins create several types of intercellular junctions that hold tissues together.

(4) Animals have two unique types of tissues: nervous tissue for impulse conduction and muscle tissue for movement. These allow them to respond rapidly to the environment.

(5) Most animals reproduce sexually

– In most, a small flagellated sperm fertilizes a larger, nonmotile egg to make a zygote

– The zygote undergoes cleavage (mitosis), forming a hollow ball of cells called the blastula.

(6) Animals are motile:

– Almost all animals have a motile stage of their life cycle. Sometimes this is a larval stage.

– Some animals develop directly through transient stages into adults (mammals), but others have distinct larval stages (many insects).

Subcategories of Animals:• The animal kingdom has many subdivisions

we focus on a few:

– Chrodates - including all the vertebrate animals

(those with a backbone).

– Arthropods - including the insects &

crustaceans