General Biology: Cell Structure, Plant & Human Body Systems

Comprehensive review of cell biology, plant anatomy and processes, organ systems, immune defense, and homeostasis mechanisms.

Cell

It is the basic structural and functional unit of all living things.

Organelle

Specialized parts of a cell that perform specific functions.

Mitochondria

Known as the powerhouse of the cell and site of cellular respiration.

Chloroplast

Plant-only organelle where photosynthesis takes place.

Photosynthesis

Process by which plants make food using sunlight, $CO_2$, and water.

Cellular respiration

Process converting glucose and oxygen into ATP, $CO_2$, and water.

ATP

Primary energy currency of the cell used for growth, repair, and movement.

Plasma membrane

Outer boundary enclosing the cell and regulating entry and exit of materials.

Nucleus

Stores DNA and produces mRNA.

Nuclear envelope

Separates the nucleus from the cytoplasm.

Cytoplasm

Gel-like interior fluid that cushions the organelles.

Endoplasmic reticulum

Processes and modifies proteins.

Golgi apparatus

Packages proteins into vesicles for export throughout the cell.

Lysosome

Contains digestive enzymes to clean up the cell.

Ribosome

Aids in protein synthesis.

Vacuole

Stores nutrients and maintains cell pressure.

Cell wall

Rigid structure supporting and protecting plant cells.

Cytoskeleton

Helps maintain cell shape and moves materials inside the cell.

Centriole

Animal-only structure helping move chromosomes during mitosis.

Diffusion

Movement of molecules from high to low concentration.

Osmosis

Movement of water through a selectively permeable membrane.

Active transport

Transport requiring energy to move substances against the gradient.

Glucose

Simple sugar produced during photosynthesis.

Xylem

Vascular tissue transporting water and minerals upward from roots to leaves.

Phloem

Vascular tissue transporting sugars from leaves to other plant parts.

Roots

Plant organ absorbing water and minerals from the soil.

Leaves

Plant organ that makes food through photosynthesis.

Stem

Plant organ serving as highway connecting roots and leaves.

Alveoli

Tiny air sacs in lungs where gas exchange occurs.

Skeletal system

System providing support, shape, and protection to the body.

Muscular system

System responsible for movement, posture, and heat generation.

Respiratory system

System taking in oxygen and removing carbon dioxide.

Circulatory system

System transporting oxygen, nutrients, and wastes throughout the body.

Hypothalamus

Part known as the body's thermostat for temperature regulation.

Shivering

Rapid muscle contraction during cold to produce heat.

Sweating

Fluid released by the body during heat to cool itself.

Thyroid gland

Gland producing thyroxine to increase metabolic rate.

Nervous system

System giving fast responses for thermoregulation.

Endocrine system

System using hormones for sustained body regulation.

Torn ACL

Injury causing unstable knee and limited mobility.

Asthma attack

Condition causing airway constriction and difficulty breathing.

Homeostasis

State of stable internal balance maintained by the body.

Lymphatic system

System filtering lymph and helping fight pathogens.

B-cells

Cells producing antibodies against pathogens.

Lymph nodes

Structures filtering lymph and trapping pathogens.

Antigen

Substance introduced by vaccines to trigger immune response.

Memory cells

Cells created after vaccination for long-term protection.

Herd immunity

Protection when many people become immune so disease spreads less.

Pathogen

Disease-causing agent that triggers immune response.

Thermoregulation

Process maintaining stable body temperature despite environmental changes.