Chapter 1.2: Life Depends on Organization and Energy

Flashcards from Chapter 1.2 of Principles of Life, 3rd Edition.

Second Law of Thermodynamics

This states that, left to themselves, organized entities tend to become more random

• Requires energy to prevent this and maintain structure

Energy

What is required to prevent complete breakdown into randomness

Catalyst

Something that speeds up a specific chemical reaction; in cells, proteins can serve this role

Circulatory system

What is often needed in multicellular organisms for specialized cells to exert their benefits effectively

Tissue

Assemblages of differentiated cells

Organ

The combination of different tissue types to accomplish specific functions

Organ system

Organs whose functions are interrelated

Ecological system (ecosystem)

Where organisms interact with each other and their physical environment

Population

Groups of individuals of any one species

Community

Populations of multiple species

Landscape

Where multiple communities of species interact

Biosphere

What the landscape of the entire Earth and all its life is known as

System

A set of interacting parts in which neither the parts nor the whole can be fully understood without taking into account the interactions

Components

The interacting parts of a biological system

Processes

The ways in which the components of a biological system interact

Dynamic

Characterized by activity or change; the body is this, using, recycling, and discarding many of its internal molecules

Feedback

When a system affects the rate of one of the earlier processes in the system

Positive feedback

Occurs in a system when a product of the system speeds up an earlier process; can lead to destabilization

Negative feedback

Occurs when a product of a system slows down an earlier process in the system; seen often in regulatory systems around a certain rate

Systems analysis

An approach used to understand systems where parts and processes are identified; B_future = B_now + A_{converted to B} - B_{converted to C}

Equilibrium

A stable balance seen often in systems, typically for negative feedback loops

Computational model

A description of a system in which the interactions among components are expressed as mathematical functions to predict model behavior

• Can be used for prediction