Community Ecology and Conservation Biology: Key Concepts
Chapter 15: Community Ecology
15.1: Defining Communities
Communities are groups of interacting species that occur together at the same place and time. They can be defined by their physical environment or by biological characteristics, such as the presence of abundant species.
Due to the impracticality of studying all species within a community, ecologists often focus on subsets like taxonomic groups, guilds, functional groups, and food/interaction webs.
15.2: Community Structure
Species diversity, a
Read MoreEnergy, Enzymes, and Biological Reactions: The Fundamentals of Life
Energy, Enzymes, and Biological Reactions
Life on Earth could not have evolved without catalysts – most of which are proteins called enzymes.
Enzymes speed up the rates of reactions by many millions of times without the need for an increase in temperature.
Enzymes are essential in metabolism, the biochemical modification and use of organic molecules and energy to support the activities of life.
Energy
Energy is defined as the capacity to do work.
Energy exists in many different forms, including heat,
Read MoreMembrane Transport: Passive, Active, and Vesicular Processes
Properties of Membranes: Read from Slides
Transport:
Transport is the controlled movement of specific ions and molecules across a membrane by membrane proteins.
Passive transport moves ions and molecules with the concentration gradient – from the side with a higher concentration to the side with a lower concentration; it is a type of diffusion; Diffusion involves a net movement of molecules or ions.
Simple Diffusion
Diffusion through the lipid part of a biological membrane depends solely on molecular
Read MoreUnderstanding Cell Biology: Structure, Function, and Processes
Cell Theory: The Foundation of Biology
Key Concepts
All living things are composed of cells, and all cells arise from earlier cells.
Cell Structures and Their Functions
Prokaryotic Cells
Prokaryotic cells are simple cells without a nucleus or membrane-bound organelles. They belong to the domains Bacteria and Archaea.
Eukaryotic Cells
Eukaryotic cells are more complex cells with a nucleus and membrane-bound organelles. They belong to the domain Eukarya and include plant and animal cells.
Organelles
Cell Wall
A
Read MoreCell Structure and Function: A Comprehensive Guide
Cytoplasm
A jellylike fluid inside the cell in which the organelles are suspended.
Works with the nucleus to keep the cell alive.
Found in both prokaryotes and eukaryotes.
Organelles
A membrane-enclosed structure with a specialized function within a cell.
Nucleus
A cell structure that contains nucleic acids, the chemical instructions that direct all the cell’s activities.
Has coded for making proteins and other important molecules.
How does the DNA work in prokaryotic
Cell Structure and Function: A Comprehensive Guide
Cytoplasm
A jellylike fluid inside the cell in which the organelles are suspended.
Works with the nucleus to keep the cell alive.
Found in both prokaryotes and eukaryotes.
Organelles
A membrane-enclosed structure with a specialized function within a cell.
Nucleus
A cell structure that contains nucleic acids, the chemical instructions that direct all the cell’s activities.
Has coded for making proteins and other important molecules.