Download 1.2 Unifying Themes of Biology

1.2 Unifying Themes of Biology
Bell ringer:
• 1- How does biodiversity depend on a
species ability to reproduce????
• 2- You respond automatically to many
different stimuli, such as loud noises. Why
might a quick response to a sound be
important??
1.2 Unifying Themes of Biology
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-vocab flash cards
1.2 Unifying Themes of Biology
KEY CONCEPT
Unifying themes connect concepts from many
fields of biology.
1.2 Unifying Themes of Biology
All levels of life have systems of related parts.
• A system is an organized group of interacting parts.
– A cell is a system of chemicals and processes.
– A body system includes organs that interact.
– An ecosystem includes living and nonliving things that
interact.
1.2 Unifying Themes of Biology
• Biologists study many different systems.
– Ex. Geneticist versus ornithologist
1.2 Unifying Themes of Biology
“How can this biology class be considered a system?”
1.2 Unifying Themes of Biology
Structure and function are related in biology.
• Structure determines function.
– Ex. Eating: bite with front & chew with molars.
– Proteins with different structures perform different
functions.
– Heart muscle cells have a different structure and
function than stomach muscle cells.
– Different species have different anatomical structures
with different functions.
1.2 Unifying Themes of Biology
“Do you think heart muscle has the same structure as arm
muscle? Why?”
1.2 Unifying Themes of Biology
Why do you shiver when cold? Sweat when hot? Feel
thirsty when you need water?
1.2 Unifying Themes of Biology
Organisms must maintain homeostasis to survive in
diverse environments.
1.2 Unifying Themes of Biology
• Homeostasis is the maintenance of constant internal
conditions.
• Its important because cells function best
within a limited range of conditions.
1.2 Unifying Themes of Biology
• Homeostasis is the maintenance of constant internal
conditions.
– Homeostasis is usually maintained through negative
feedback.
– Negative feedback systems return a condition to its
normal (set) point.
1.2 Unifying Themes of Biology
• Behaviors and adaptations can help maintain
homeostasis.
– Ex. Basking reptiles
1.2 Unifying Themes of Biology
BELL RINGER
• So far we have discussed 3 Unifying Themes in Biology.
What are they?...................
• When you are finished look over your terms!
1.2 Unifying Themes of Biology
“Why is homeostasis important?”
1.2 Unifying Themes of Biology
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.
- Supported by fossil record & genetic comparisons
1.2 Unifying Themes of Biology
– Evolution can occur through natural selection of
adaptations.
– Adaptations are beneficial inherited traits that are
passed to future generations.
– Populations can also change due to different
environments.
1.2 Unifying Themes of Biology
–Ex. Finches
1.2 Unifying Themes of Biology
• Evolution accounts for both the diversity and the unity of
life.
• Shared characteristics result from common evolutionary
descent.
– Ex. Humans versus bacteria
1.2 Unifying Themes of Biology
“How does evolution lead to both diversity & similarities of
life?”