Fundamental Cellular Processes: DNA, Gene Expression, Energy
DNA Replication In Vitro: Polymerase Chain Reaction
DNA Replication: Parental strands separate, complementary strands are made, and daughter strands are created.
Polymerase Chain Reaction (PCR): A method of making copies, allowing a targeted region of DNA to be replicated (amplified) into as many copies as desired. PCR requires:
- Template DNA
- DNA Polymerase
- Four bases (dNTPs)
- Two primers
This process makes 2n copies.
Oligonucleotides: Primer sequences, typically 20-30 nucleotides long, are added so the number
Read MoreKey Ecological Concepts: Productivity, Homeostasis, Energy Flow, Nitrogen Cycle
Understanding Ecological Productivity
Productivity refers to the amount of organic matter, or food, prepared by a plant. When measured at any unit of time, it is known as the rate of productivity of that ecosystem.
Productivity is categorized into the following types:
- Primary Productivity
- Secondary Productivity
- Net Productivity
Primary Productivity
Primary productivity is the production capability of a plant. It is always associated with autotrophs or photosynthetic organisms, primarily green plants. Some
Read MoreAnimal Physiology: Response Mechanisms
Motor Responses and Locomotion
Motor responses are linked to the behavior of animals. They are responses that involve some kind of movement, with or without displacement. The effector organs for these responses are the muscles.
The Muscular System
The muscular system is formed by organs called muscles, consisting of muscle tissue and elongated cells called muscle fibers. Their cytoplasm has a large number of myofilaments (actin and myosin) with contractile function.
The muscles of invertebrates and
Read MoreTypes of Biological Tissues
Plant Tissues
Meristematic Tissues
Allow for growth. Their cells are small with thin cell walls, a large nucleus, and no intercellular spaces.
- Primary Meristems: Responsible for growth in length (apical meristems) and formation of primary phloem and xylem. Apical meristems are the most important.
- Secondary Meristems: Responsible for growth in girth (diameter). Examples include:
- Cambium: Forms secondary xylem and phloem internally.
- Phellogen: Originates cork tissue externally and inner cortical parenchyma.
Foundational Concepts in Biology: Animal & Plant Systems
Animal Biology Fundamentals
Animal Tissue Types
Animal tissues are classified into four primary types: epithelial, connective, muscular, and nervous. Epithelial tissue covers body surfaces and lines organs, aiding in protection and absorption. Connective tissue supports and binds other tissues; it includes blood, bone, cartilage, and adipose tissue. Muscular tissue enables movement and is divided into skeletal, smooth, and cardiac types. Nervous tissue, composed of neurons and neuroglia, transmits
Read MorePhotosynthesis: How Plants Power Life
Foundations of Life’s Energy
Life on Earth fundamentally relies on two critical elements: the sun and the process of photosynthesis.
Capturing Solar Energy
For photosynthesis to occur, autotrophs (organisms that produce their own food) must capture light energy directly from the sun.
How Sunlight Reaches Earth
Energy travels from the sun to Earth primarily in the form of light.
The Colors of Sunlight
Although the sun’s light appears white, it is composed of various wavelengths, visible as the colors of
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