Anatomy and Evolution: Key Concepts

• Anatomy/Evolution Test Topics

Anatomical Orientation

• Dorsal refers to the back or upper side.
• Ventral refers to the front or lower side.
• Anterior means towards the front.
• Posterior means towards the back.

Circulatory Systems

• Open circulatory systems pump blood into a hemocoel where blood bathes the organs directly.
• Closed circulatory systems have blood contained in vessels, separate from the interstitial fluid.

Body Temperature Regulation

• Cold-blooded animals (ectotherms) rely on external sources for body heat.
• Warm-blooded animals (endotherms) generate their own body heat internally.

Body Plan

• Bilateral symmetry involves a body plan with a left and right side that are mirror images.

Body Systems

• The nervous system's purpose is to transmit signals between different parts of the body and to coordinate actions and sensory information.

Reproduction

• Sexual reproduction in the animal kingdom serves to increase genetic variation.

Organ Functions

• Esophagus transports food to the stomach.
• Intestines are responsible for nutrient absorption.
• The brain controls bodily functions.
• A 3-chambered heart has two atria and one ventricle.
• A 4-chambered heart has two atria and two ventricles.
• Endoskeletons are internal support structures.
• Exoskeletons are external support structures.
• Testes produce sperm.
• Ovaries produce eggs.
• Nerves transmit electrical signals.
• The spinal cord connects the brain to the rest of the body.
• Kidneys filter waste from the blood.
• Lungs facilitate gas exchange.

Classification

• Taxonomy involves the science of naming and classifying organisms.
• Phylogeny is the study of the evolutionary history and relationships among individuals or groups of organisms.
• Cladograms are diagrams that show the evolutionary relationships among a group of organisms, and Dichotomous keys are tools used to identify organisms based on contrasting characteristics.

Adaptations

• Physical adaptations are structural features that enhance survival.
• Behavioral adaptations are actions that enhance survival.

Evolutionary Processes

• Natural selection involves the differential survival and reproduction of individuals due to differences in phenotype.
• Natural selection is a naturally occurring process, while artificial selection is driven by humans selecting for desired traits.

Species

• Species refers to a group of organisms that can interbreed and produce fertile offspring.
• Speciation is the process by which new species arise.
• Isolation can lead to speciation, which increases biodiversity.

Genetic Change

• Recombination involves the rearrangement of genetic material.
• Mutation involves changes in the DNA sequence, both cause genetic change.

Evolutionary Evidence

• Homologous structures indicate common ancestry, suggesting divergent evolution.
• Vestigial traits are remnants of structures that once had a function in an ancestor, and they provide evidence of evolution.

Population Dynamics

• Overproduction, competition, and variation are key components of natural selection.

Explore core concepts in anatomy and evolution. Learn about anatomical orientation (dorsal, ventral, anterior, posterior), circulatory systems (open vs. closed), and body temperature regulation (ectotherms vs. endotherms). Understand body plans, nervous system functions, and the importance of sexual reproduction for genetic variation.