Biology Chapter: Cell Structure and Function

Study Notes

Cell Structure and Function

Cells are the fundamental units of life, exhibiting a diverse range of structures and functions.
All cells share some common features, including a plasma membrane, cytoplasm, and genetic material (DNA).
Prokaryotic cells (bacteria and archaea) lack a nucleus and membrane-bound organelles, while eukaryotic cells (animals, plants, fungi, protists) possess a nucleus and various organelles.
The plasma membrane regulates the passage of substances into and out of the cell.
Cytoplasm is the jelly-like substance filling the cell, containing various organelles.
Organelles are specialized structures with specific functions within the cell, for example, mitochondria are responsible for energy production.

Biological Molecules

Four major classes of biological molecules are essential for life: carbohydrates, lipids, proteins, and nucleic acids.
Carbohydrates provide energy and structural support. Common examples include sugars and starches.
Lipids store energy, form cell membranes, and act as hormones. Examples include fats, oils, and steroids.
Proteins are involved in diverse functions, such as structural support, enzymatic activity, and transport. Examples include enzymes and antibodies.
Nucleic acids (DNA and RNA) store and transmit genetic information. DNA stores the genetic code, while RNA plays a role in protein synthesis.

Cell Metabolism

Metabolism encompasses all chemical reactions occurring within a living organism.
Catabolism breaks down complex molecules into simpler ones, releasing energy.
Anabolism builds complex molecules from simpler ones, requiring energy input.
Cellular respiration is a critical metabolic pathway that breaks down glucose to produce ATP, the cell's primary energy currency.
Photosynthesis is a process unique to plants and some other organisms, converting light energy into chemical energy in the form of glucose.

Cell Communication

Cells communicate with each other to coordinate activities and respond to stimuli.
Signal transduction pathways relay signals from the cell's exterior to its interior.
Cell-cell recognition and signaling involve surface proteins and receptors.
Hormones and neurotransmitters are examples of signaling molecules involved in long-distance communication.

Genetics

Genetics is the study of heredity and variation in living organisms.
DNA carries the genetic information, which is transcribed into RNA and translated into proteins.
Genes are segments of DNA containing the instructions for making specific proteins.
Mutations in DNA can lead to changes in the genetic code and potentially alter traits.
Mendelian genetics describes patterns of inheritance for traits.
Chromosomes are organized structures of DNA and proteins that carry genes.
Meiosis is the process of cell division that produces gametes (sex cells) with half the number of chromosomes.
Mitosis is the process of cell division that produces identical copies of cells.

Evolution

Evolution is the process of change in the heritable characteristics of biological populations over successive generations.
Natural selection is a key mechanism of evolution, where organisms with advantageous traits are more likely to survive and reproduce.
The theory of evolution explains the diversity of life on Earth.
Common ancestry connects all living organisms, demonstrating shared evolutionary history.

Description

Explore the fundamental units of life in this quiz, focusing on cell structure and function. Learn about prokaryotic and eukaryotic cells, their organelles, and essential biological molecules. Test your knowledge on how these components contribute to life.