Ecosystem Energy Flow, Nutrient Cycles, and Plant Responses

Food: Contains energy and nutrients required for maintenance/survival, growth/development, and reproduction.

Carbon:

  • Auto (from CO2, inorganic)
  • Hetero (from organic molecules)

Energy:

  • Photo (from light)
  • Chemo (oxidizing inorganic or organic molecules)

Organisms:

  • Prokaryotes: Have all carbon and energy types.
  • Protists: Photoautotrophs and chemoheterotrophs.
  • Plants: Photoautotrophs and chemoheterotrophs.
  • Fungi and Animals: Chemoheterotrophs.

Food Chains: Show how energy & nutrients move between organisms.

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Common Diseases: Etiology, Symptoms, and Management

Urinary Tract Infections

Etiopathogenesis: It depends on several factors, including host factors, bacterial virulence factors, and anatomical and physiological factors. Host factors— Factors that impair the immune response, such as immunosuppressive medications, HIV infection, or diabetes, can increase the risk of UTI. In addition, female anatomy (shorter urethra and closer proximity of urethral opening to the anus) makes women more prone to UTIs.

Clinical manifestations:

  • A strong, persistent urge
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Understanding Allergy, Immunity, and Genetics

Allergy and Immune Response

Allergy

Anti-allergen interacts with mast cells, leading to histamine production and other cellular blood circulation effects.

Humoral Response

B lymphocytes produce antibodies (AC) that bind to antigens. AC functions include:

  • Neutralizing antigens
  • Agglutination
  • Precipitation
  • Activation of the complement system (a group of inactive proteins in plasma)

Cellular Response

Macrophages present antigens on their surface along with Major Histocompatibility Complex (MHC) proteins. This

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Scientific Method and Biology: Key Concepts Explained

The Scientific Method

The scientific method is a process used across all sciences. The steps include:

  • Observation of events
  • Formulation of a hypothesis
  • Corroboration of hypotheses through testing
  • Development of a theory

Scientific Knowledge

Scientific knowledge is limited to what can be perceived directly by the senses or through instruments that amplify the senses.

Biology: The Study of Life

Biology is the science that studies living organisms. Fields of study include:

  • Descriptive or Structural Biology:
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Cell Biology, Evolution, and Primordial Earth: Key Concepts

Cell Division and Processes

Interphase (I): Distinct nucleus, normal cell functions.

Prophase (P): Nuclear membrane breaks down, chromosomes condense, spindles form.

Metaphase (M): Chromosomes line up across the equator of the cell.

Anaphase (A): Chromatids migrate to poles.

Telophase (T): Two new nuclei form, chromosomes decondense.

Cytokinesis (C): Cytoplasm divides, resulting in two new cells.

Translation

  1. mRNA binds to ribosome.
  2. mRNA advances until AUG (start codon) is at the P site.
  3. tRNA binds to codon
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The Human Nervous System: Structure and Function

Central Nervous System

The central nervous system (CNS) is formed by the brain and spinal cord. It is responsible for processing received information and controlling body functions.

Peripheral Nervous System

The peripheral nervous system (PNS) is formed by a set of nerves that connect the CNS with the rest of our body organs. Its function is to transmit information and conduct the CNS’s orders to the organs responsible for executing them.

Brain

The brain is located in the skull. It consists of the cerebrum,

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