[Chapter 25] Plants and Animals - Common Challenges Part II Flashcards
02/13/14, Quiz 1 (This deck covers textbook chapters 25.4 to 25.5)
Homeostasis
Interactions between cells in tissues, organs, and organ systems that keep the operating conditions of the internal environment within tolerable limits.
Anatomy
Study of body form, its morphology
Physiology
study of patterns and processes by which an individual survives and reproduces in the enviroment
Tissue
A community of cells and extracellular substances that interact in one or more tasts
Organ
A structural unit made up of tissues arranged in proportions and patterns that allow it to carry out a specific task(s)
Organ System
Organs that interact in one or more tasks Ex. Lungs and airways are organs of the respiratory system of land vertebrates
Growth vs Development
Growth - Refers to an increase in the number, size, and volume of cells. Measure in quantitative terms.Development - Series of stages in which specialized tissues, organs, and organ systems form in heritable patterns. Measure in qualitative terms.
Flower
Reproductive organ
Respiratory System
Gases only move into and out of an animal by diffusing across a moist surface. Land animals contain moist sacs for gas exchange within the body.
Extracellular Fluid and components
Body fluid not inside cells, acts as an internal environment. The body requires a stable fluid environment for its cells.Interstitial Fluid - Type of extracellular fluid, fills spaces between cells and tissues Plasma - fluid portion of cells
Diffusion
When ions or molecules of a substance are concentrated in one place, they tend to move to a place where they are not as concentrated. Plants and animals keep gases diffusing in directions most suitable for metabolism and cell survival.
Vascular Tubes
Systems of tubes through which substances move to and from cells
Active Transport
Protein pumps one specific solute from a region of low concentration to one of higher concentration.
Signalling Mechanisms
Guide how the plant or animal body grows, develops, and maintains itself, and also reproduces
Biotic
Living
Sensory receptors
Cells of cell parts that detect stimuli, which are specific forms of energy
Integrator
A central command post that receives and processes information about stimuli, issues signals to effectors
Effectors
Muscles, glands, or both, that carry out suitable responses to the stimulation
Feedback Mechanisms
Major homeostatic controls, help maintain physical and chemical aspects of the body’s internal environment within ranges that its individual cells can operate
Negative Feedback Mechanisms
An activity changes a specific condition in the internal environment, and when the condition changes past a point, a response reverses the change
Positive Feedback Mechanisms
Mechanisms spark a chain of events that intensify change from an original condition, in a living organism this intensification will lead to a change that ends the feedback
System Acquired Resistance
A defence response to infections and injured tissues. Cells in an affected tissue release signalling molecules that call for the synthesis and release of organic compounds that will protect the plant against attacks.
Compartmentalization
Trees will wall off the damaged tissue, release phenols (and other toxic compounds) and often secrete resins. Compartments form around injured, infected, or poisoned tissues, and new tissues grow overtop.
Leaf folding
A controlled response by Lupinus arboreus to changing conditions. Response minimizes heat absorption.
Circadian Rhythm
Biological activity pattern that recurs with an approximate 24-hour cycle. Phytocrome helps control this.
Homeostasis in Plants
There are control mechanisms (compartmentalization, system acquired resistance, and rhythmic leaf movements) that help maintain homeostasis, but they are not centrally controlled like in animals.
Things involved in Communication Among Distant Cells
Amino acids, peptides, proteins, lipids, and gases. Some other signals diffuse through interstitial fluid, or through blood vessels or vascular tissues.
Molecular Mechanisms in Cell Communication
Often have three steps:1. Specific Receptor is activated2. Signal is transduced (converted into a form that can operate inside the cell)3. Cell makes a response to the signal (ex. altering its metabolism or which genes it expresses)
Responses to Molecular Signals
Many receptors that respond are membrane proteins, and once activated some will activate an enzyme that will activate more of a different kind of enzyme, and so on.
Cascading Reactions
Amplify the response to one signal many times over
Apoptosis
The process of programmed cell death. Example of a response to signal reception.