Core Concepts in Biology: Reproduction, Homeostasis, and Gas Exchange
Human Reproductive System Anatomy
Male Reproductive System
The male reproductive system components and their functions:
- Testicles: Produce sperm and testosterone.
- Epididymis: The reservoir for sperm, communicating with the testicles.
- Scrotum: Holds the testicles outside the body to maintain a temperature lower than core body temperature, which is essential for sperm viability.
- Seminal Duct (Vas Deferens): Transports sperm from the epididymis to the urethra.
- Urethra: A duct where the seminal ducts converge
Animal Kingdom Classification: Phyla, Embryology, and Vertebrate Groups
Invertebrates: The Animal Kingdom (Part 1)
Animals are characterized by their ability to move (motility).
Stages of Animal Embryonic Development
The formation of tissues and organs begins with three primary germ layers:
- Endoderm: The inner layer, which forms the digestive organs.
- Ectoderm: The external layer, which forms the nervous system and external coatings (skin).
- Mesoderm: The intermediate layer, which forms muscles, bones, and circulatory systems.
Classification by Tissue and Symmetry
- Parazoa (Subkingdom)
Essential Concepts of Human Circulation and Lymphatic Health
Key Functions of the Lymphatic System
The lymphatic system performs several vital roles:
- Fluid Collection: Collects excess interstitial fluid and returns it to the blood circulation.
- Fat Absorption: Absorbs and transports dietary fats in the intestine.
- Immune Defense: Defends the body from bacteria and other foreign particles.
This filtering process is primarily carried out by lymphocytes, which are especially abundant in the lymph nodes. When there is an infection, lymph nodes typically swell (become
Read MoreCellular Energy Metabolism and Regulation
Blood Glucose Regulation and Signaling
Specificity: Only cells with the appropriate receptor respond to a signal. Sensitivity: Signals are amplified, allowing them to work effectively at low concentrations.
Hormone Classification and Receptors
Hormones are categorized into three structural groups:
- Derivatives of Amino Acids (e.g., Epinephrine): Mostly not lipid soluble; bind to receptors on the surface of the target cell.
- Proteins (e.g., Insulin and Glucagon): Not lipid soluble; bind to receptors on
Cellular Anatomy: Structure and Function of Eukaryotic Organelles
Cell Structure and Function: The Basic Units of Life
Foundations of Cell Theory
The cell is the basic unit of structure and function of living things. All living things are composed of cells. All cells arise from other cells by the process of cell division. Scientists Schleiden and Schwann established these key tenets of cell theory.
Key Components of the Cell (Organelles)
Plasma Membrane
- Structure: A double layer of phospholipids (a lipid molecule combined with a phosphate group).
- Function: Controls
Core Concepts in Microbiology: Genetics, Ecology, and Immunity
Bacterial Genetics and Molecular Processes
Genome Replication and Gene Expression
Foundational Genetic Experiments
Griffith’s transformation experiment demonstrated that non-virulent bacteria could become virulent by absorbing DNA from dead virulent cells, proving that DNA is the genetic material. The Hershey and Chase experiment used radioactive labeling (phosphorus for DNA and sulfur for protein) to confirm that only DNA enters bacterial cells during phage infection, further establishing DNA as
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