Ch. 1 – Life & Scientific Method

Characteristics of Life

Biologists use specific characteristics to define living organisms. Understanding these traits helps distinguish living things from non-living matter.

• Seven Characteristics of Life: Organization, metabolism, responsiveness, growth, development, reproduction, and homeostasis.

• Examples: Metabolism (energy use), reproduction (offspring production), and homeostasis (maintaining internal balance).

Classification of Living Organisms

Organisms are grouped based on shared characteristics. Classification helps scientists organize and understand the diversity of life.

• Classification System: Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species.

• Species: The most specific classification, representing a group of organisms capable of interbreeding.

• Human Classification: Homo sapiens.

Scientific Method

The scientific method is a systematic approach to investigating natural phenomena.

• Steps: Observation, hypothesis formation, experimentation, data collection, analysis, and conclusion.

• Application: Used in daily life to solve problems and answer questions scientifically.

Ch. 2 – Chemistry

Atoms and Molecules

All matter is composed of atoms, the smallest identifiable units of elements. Understanding atomic structure is fundamental to biology.

• Atom: Consists of protons, neutrons, and electrons.

• Elements: Substances made of one type of atom (e.g., carbon, hydrogen).

• Compounds: Substances formed from two or more elements chemically bonded.

• Isotopes: Atoms of the same element with different numbers of neutrons.

Properties of Water

Water is essential for life due to its unique chemical and physical properties.

• Polarity: Water molecules have a partial positive and negative end, allowing hydrogen bonding.

• Solvent: Water dissolves many substances, facilitating chemical reactions in cells.

• High Specific Heat: Water resists temperature changes, helping regulate body temperature.

pH and Acids/Bases

The pH scale measures the concentration of hydrogen ions in a solution.

• pH Scale: Ranges from 0 (acidic) to 14 (basic), with 7 being neutral.

• Acids: Release hydrogen ions () in solution.

• Bases: Accept hydrogen ions or release hydroxide ions ().

• Formula:

Organic Molecules

Organic molecules are carbon-based and essential for life. They include carbohydrates, lipids, proteins, and nucleic acids.

• Carbohydrates: Provide energy and structural support.

• Lipids: Store energy and form cell membranes.

• Proteins: Serve as enzymes, structural components, and signaling molecules.

• Nucleic Acids: Store and transmit genetic information (DNA, RNA).

Ch. 3 – Cells/Metabolism

Cell Structure and Function

Cells are the basic units of life. They can be prokaryotic (no nucleus) or eukaryotic (with nucleus).

• Prokaryotes: Bacteria and Archaea; lack membrane-bound organelles.

• Eukaryotes: Animals, plants, fungi, and protists; have membrane-bound organelles.

• Cell Membrane: Phospholipid bilayer that controls entry and exit of substances.

• Organelles: Specialized structures (e.g., nucleus, mitochondria, endoplasmic reticulum).

Cellular Respiration

Cellular respiration is the process by which cells convert glucose and oxygen into energy (ATP), carbon dioxide, and water.

• Inputs: Glucose and oxygen.

• Outputs: ATP, carbon dioxide, and water.

• Stages: Glycolysis, Krebs cycle, electron transport chain.

• Equation:

• ATP: Main energy currency of the cell.

Anabolism vs. Catabolism

Anabolism builds complex molecules from simpler ones, while catabolism breaks down molecules to release energy.

• Anabolism: Synthesis of proteins from amino acids.

• Catabolism: Breakdown of glucose during cellular respiration.

Ch. 4 – Tissues/Skin

Types of Tissues

The human body is composed of four primary tissue types, each with specific functions.

• Epithelial Tissue: Covers body surfaces and lines cavities; functions in protection, absorption, and secretion.

• Connective Tissue: Supports, binds, and protects organs (e.g., bone, blood, adipose).

• Muscle Tissue: Responsible for movement (skeletal, cardiac, smooth).

• Nervous Tissue: Transmits electrical impulses for communication.

Integumentary System (Skin)

The integumentary system includes the skin, hair, nails, and associated glands. It protects the body and helps regulate temperature.

• Layers of Skin: Epidermis (outer), dermis (middle), hypodermis (inner).

• Functions: Protection, sensation, thermoregulation, vitamin D synthesis.

• Cells: Keratinocytes (produce keratin), melanocytes (produce melanin), Langerhans cells (immune function).

• Hair and Nails: Provide protection and aid in sensation.

Ch. 5 – Skeletal System

Functions of the Skeletal System

The skeletal system provides structure, protection, and support for the body. It also facilitates movement and produces blood cells.

• Functions: Support, protection, movement, mineral storage, blood cell production (hematopoiesis).

Types of Bones and Bone Tissue

Bones are classified by shape and structure. Bone tissue is dynamic and constantly remodeled.

• Bone Types: Long, short, flat, irregular, and sesamoid bones.

• Bone Cells: Osteoblasts (build bone), osteocytes (maintain bone), osteoclasts (break down bone).

• Compact vs. Spongy Bone: Compact bone is dense and strong; spongy bone is lighter and contains red marrow.

Axial vs. Appendicular Skeleton

The human skeleton is divided into axial and appendicular components.

Joints and Movement

Joints connect bones and allow for movement. They are classified by structure and function.

• Types: Fibrous (immovable), cartilaginous (slightly movable), synovial (freely movable).

• Examples: Knee (synovial), intervertebral discs (cartilaginous), skull sutures (fibrous).

Additional info: Some details, such as specific cell types and examples, have been expanded for academic completeness.