Biology Cell Structure and Functions

Study Notes

Cell Theory

All living organisms are composed of cells.
The cell is the basic unit of life.
All cells arise from pre-existing cells.

Cellular Structures

Prokaryotic Cells: Lack a nucleus, generally smaller (e.g., bacteria).
Eukaryotic Cells: Have a nucleus and organelles, larger (e.g., plants, animals).
Organelles examples: Mitochondria (energy production), Ribosomes (protein synthesis), Golgi apparatus (modification and packaging of proteins).

Genetic Material

DNA: Contains genetic instructions, double-helix structure.
RNA: Single-stranded, involved in protein synthesis (mRNA, tRNA, rRNA).
Genes: Segments of DNA that code for proteins.

Photosynthesis

Process by which green plants, algae, and some bacteria convert light energy into chemical energy.
Main equation: 6CO2 + 6H2O + light energy → C6H12O6 + 6O2.
Key locations: Chloroplasts in plant cells.

Cellular Respiration

Process of converting glucose into ATP (energy).
Three main stages: Glycolysis, Krebs cycle, Oxidative phosphorylation.
Equation: C6H12O6 + 6O2 → 6CO2 + 6H2O + ATP.

Evolution and Natural Selection

Evolution: Change in the heritable characteristics of biological populations over successive generations.
Natural Selection: Mechanism of evolution where organisms better adapted to their environment tend to survive and produce more offspring.

Ecosystems

Composed of living (biotic) and non-living (abiotic) components.
Energy flow: Sun → producer (plants) → consumer (animals) → decomposer (fungi/bacteria).
Trophic levels: Producers, Primary consumers, Secondary consumers, Tertiary consumers.

Human Body Systems

Circulatory System: Transports nutrients and oxygen to cells; includes heart, blood, and blood vessels.
Respiratory System: Facilitates gas exchange (O2/CO2); includes lungs and airways.
Nervous System: Controls bodily functions and responses; includes the brain, spinal cord, and nerves.

Genetics

Mendelian Genetics: Study of inheritance and variations; includes laws of segregation and independent assortment.
Dominant and Recessive Alleles: Dominant alleles mask the effect of recessive alleles in heterozygotes.

Biotechnology

Use of living systems to develop or make products; includes genetic engineering, CRISPR, and cloning.
Applications: Medicine (gene therapy), agriculture (GMO crops), and environmental management.

Ecology

Study of interactions among organisms and their environment.
Key concepts: Habitat, niche, population dynamics, and biodiversity.
Conservation: Efforts to protect ecosystems and species from extinction.

Description

This quiz covers the essential concepts of cell theory, cellular structures, and the processes of photosynthesis and cellular respiration. Test your knowledge on prokaryotic and eukaryotic cells, as well as the roles of DNA and RNA in genetics. Prepare to explore the fundamental units of life and their functions!