Biology 1: Prokaryotic and Eukaryotic Cells

Study Notes

Cell Types Overview

Cells are categorized into two main types: prokaryotic and eukaryotic.
Prokaryotic cells are typically unicellular and lack membrane-bound organelles.
Eukaryotic cells can be unicellular or multicellular and possess membrane-bound organelles.

Prokaryotic Cells

Genetic material of prokaryotes is found in a region called the nucleoid.
Prokaryotes do not have a true nucleus; their genetic material is suspended in the cytoplasm.
Exhibit various arrangements: single, pairs, chains, clusters, aggregates, and colonies.

Eukaryotic Cells

Eukaryotic cells contain a true nucleus; the term "eukaryote" derives from "eu" (true) and "karyon" (nucleus).
Include organisms such as protozoans, algae, fungi, plants, and animals.
Eukaryotic cells can function independently as single-celled organisms or as part of multicellular structures.

Taxonomy

Taxonomy is the science of naming and classifying organisms.
It involves systematic classification of plants and animals in hierarchical groups.
Linnean Binomial Nomenclature is the method used for naming organisms, reflecting their classification.

Adaptations in Cell Structure

Cells may undergo modifications to adapt and perform specialized functions, which illustrates the diversity of life forms.
Understanding cell structure and function is crucial for studying biological systems and the evolution of life.

Learning Objectives

Distinguish prokaryotic and eukaryotic cells based on key features.
Classify different types of cells and specify their functions.
Describe cellular modifications that allow adaptation for specialized tasks.

Learning Objectives

Describe structural components of the cell membrane.
Relate cell membrane structure to its function.
Explain how the cell membrane regulates material transport.
Differentiate between endocytosis and exocytosis.

Cell Membrane Overview

Separates intracellular and extracellular environments.
Enables specific chemical exchanges vital for life.
Composed of a semipermeable phospholipid bilayer.

Phospholipid Bilayer

Main component of cell membranes.
Phospholipids arrange in a bilayer, creating a barrier against water-soluble molecules.

Phospholipid Structure

Comprises a polar hydrophilic head (glycerol + phosphate group) and two non-polar hydrophobic tails (fatty acids).
Amphipathic nature: possesses both hydrophilic and hydrophobic regions.

Cholesterol in Cell Membrane

Regulates membrane fluidity.
Prevents phospholipids from packing too closely, reducing membrane freezing risk.

Membrane Proteins

Integral proteins span the bilayer and facilitate diffusion and cell recognition.
Transport proteins traverse the bilayer to aid the movement of substances.
Channel proteins allow passive transport of ions and polar molecules along concentration gradients.
Carrier proteins can change shape to transport substances across gradients.

Glycoproteins and Glycolipids

Glycoproteins have carbohydrate chains that function as receptors and cell markers for recognition.
Glycolipids stabilize the membrane and support immune responses via hydrogen bonding with water molecules.

Transport Mechanisms in Cells

Cell membranes regulate solute movement using embedded proteins for various functions.
Four processes for solute transport:
- Passive diffusion: Movement down a concentration gradient without energy.
- Carrier-mediated transport: Movement down a gradient using carrier proteins.
- Primary active transport: Movement against a gradient, requiring energy.
- Secondary active transport: Co-transport against a gradient, utilizing energy indirectly.

Passive Transport

Involves movement of substances without energy expenditure, relying on membrane permeability.

Description

Explore the fundamental differences between prokaryotic and eukaryotic cells in this quiz. You'll classify various cell types, specify their functions, and learn about adaptations. Perfect for Biology 1 students looking to deepen their understanding of cellular biology.