Biology Exam Prep: Chapters 4-6 Flashcards

Study Notes

Cell Anatomy and Types

Anatomy refers to the structural composition of living cells, which includes both animal and plant cells.
Prokaryotic cells lack a nucleus and membrane-bound organelles, while eukaryotic cells have both.
Plant cells contain a cell wall, chloroplasts for photosynthesis, and larger vacuoles compared to animal cells.

Cell Theory Principles

All cells arise from pre-existing cells, underscoring the continuity of life.
Cells are the fundamental units of structure and function in all organisms.
All living things are composed of one or more cells, forming the basis of biological organization.

Key Scientists Contribution

Robert Hooke: Coined the term "cell" after observing cork structures.
Anton van Leeuwenhoek: Created microscopes for studying individual living cells.
Matthias Schleiden: Proposed that all plants are made up of cells.
Theodor Schwann: Asserted that all animals consist of cells.
Rudolf Virchow: Highlighted that cells arise from other cells, reinforcing cell theory.

Mitochondria and Chloroplasts

Mitochondria feature inner cristae membranes that enhance the surface area for energy production.
Chloroplasts contain thylakoid membranes arranged in stacks called grana for photosynthetic reactions.
Both organelles support the endosymbiotic theory, indicating their evolutionary origins from engulfed prokaryotes.

Ribosomes and Protein Synthesis

Ribosomes are essential for protein synthesis and can be found free in the cytoplasm or bound to the endoplasmic reticulum.
Protein synthesis involves mRNA being translated into polypeptides, occasionally interacting with the endoplasmic reticulum for folding and modification.

Endomembrane System

The nucleus transcribes information into mRNA, which is transported outside for processing.
Proteins synthesized by ribosomes move through the rough endoplasmic reticulum to be further modified.
Vesicles transport proteins to the Golgi apparatus which sorts and packages them for secretion or use within the cell.

Surface Area and Cell Efficiency

Smaller cells demonstrate a higher surface-area-to-volume ratio, enhancing nutrient absorption and waste elimination.
As cell size increases, surface area grows slower than volume, making smaller cells more efficient metabolically.

Organelles and Their Functions

The Golgi apparatus modifies, sorts, and packages proteins, using signal proteins for transport.
Lysosomes contain hydrolytic enzymes for breaking down waste materials and cellular debris.
Endoplasmic reticulum exists in two forms: rough (with ribosomes) and smooth (lipid synthesis).

Overview of Prokaryotic Cells

Prokaryotic cells possess a cell envelope comprising the plasma membrane, cell wall, and sometimes a glycocalyx for protection and adherence.
Genetic material is found in the nucleoid and may include plasmids for additional genetic functions.
Structures like flagella and fimbriae enhance mobility and attachment to surfaces.

Description

Prepare for your biology exam with these flashcards covering crucial concepts from Chapters 4 to 6. Review key terms like anatomy, membrane compartmentalization, and cell theory to strengthen your understanding of cell structure and function. Perfect for quick revision and memorization!