Core Concepts in Biology: Evolution, Classification, and Life Forms
Evolutionary Biology Fundamentals
- The original source of all genetic variation is: Mutation
- Microevolution occurs when: Changes in allele frequencies in a population occur over generations.
- What is the only evolutionary mechanism that consistently leads to adaptive evolution? Natural selection.
- The evolutionary effects of genetic drift are greatest when: The population size is small.
- Which of the following descriptions illustrates phenotypic variation caused by the environment? Diet of caterpillars changes
Genetic Engineering and Stem Cells: Advances in Biotechnology
The Genetic Engineering Process
Genetic engineering involves a precise process:
- The DNA containing the desired gene is cut with specific restriction enzymes.
- Vector DNA is cut with the same restriction enzymes to ensure complementary ends.
- The DNA fragment with the desired gene is ligated (bound) to the vector.
- The resulting molecule is recombinant DNA (DNA from different sources). This recombinant DNA is then introduced into a host cell.
- The host cell, typically a bacterium, divides many times, creating
Essential Medical Concepts: Diseases, Treatments, and Body Systems
Common Health Conditions
Malformations and Birth Defects
Malformations are conditions present at birth, resulting from disorders during embryonic development or childbirth.
Autoimmune Diseases
Autoimmune diseases are conditions where the immune system mistakenly attacks the body’s own tissues, producing molecules (antibodies) that cause damage to various organ systems. Examples include systemic lupus erythematosus, rheumatoid arthritis, and multiple sclerosis. Immunomodulator drugs can help control
Read MoreBiological Classifications: Kingdoms, Organisms, and Bacteria
Kingdom Plantae: Characteristics
Composed of multicellular, eukaryotic, autotrophic, photosynthetic organisms. They exhibit a vast variety in form and dimensions, ranging from small plants like mosses to giant trees, all capable of photosynthesis.
Kingdom Animalia: Metazoa
Includes all animals. These are multicellular eukaryotic organisms whose cells associate to form tissues. They are heterotrophic, feeding on organic compounds, and primarily reproduce sexually (via egg and sperm).
Key Metazoan Phyla
- Sponges
Human Body Systems: Anatomy and Physiology for Performance
Skeletal System Functions
Protects the body’s organs: Ribs and sternum protect the heart and lungs; the cranium protects the brain; the pelvis protects the intestines.
Allows movement: Movement is achieved through the use of joints and muscle attachment. Without the ability to use our muscles for movement, sports would be impossible to play.
Helps formation of blood cells: Platelets, red blood cells, and most white blood cells are produced in the bone marrow.
Stores minerals: Bones store calcium and
Specialized Diets and Clinical Nutritional Interventions
Isolation Diet
The Isolation Diet is a monotonous diet, low in bacteria, indicated for patients with immunosuppression or hematologic malignancies. It often leads to suboptimal nutrient intake, aggravated by factors such as prolonged hospital stays, physical isolation, discomfort associated with chemotherapy treatment, and depression. This diet consists of cooked or pasteurized foods with minimal handling during preparation. It strictly excludes raw foods, including vegetables and unpeeled fruits.
Read More