Biology Chapter on Cells and Genetics

Cell Structure and Function

• Cell Types:

  • Prokaryotic: No nucleus, smaller, simpler (e.g., bacteria).
  • Eukaryotic: Has a nucleus, larger, more complex (e.g., plants, animals).

• Cell Organelles:

  • Nucleus: Contains genetic material.
  • Mitochondria: Energy production (ATP).
  • Ribosomes: Protein synthesis.
  • Endoplasmic Reticulum (ER): Synthesizes proteins (rough ER) and lipids (smooth ER).
  • Golgi Apparatus: Modifies and packages proteins.
  • Lysosomes: Digests waste materials.
  • Chloroplasts: Photosynthesis (in plants).

Genetics

• DNA Structure: Double helix, composed of nucleotides (A, T, C, G).

• Gene Expression:

  • Transcription: DNA to mRNA.
  • Translation: mRNA to protein at ribosomes.

• Mendelian Genetics:

  • Dominant and recessive alleles.
  • Punnett squares for predicting trait inheritance.

• Mutations: Changes in DNA sequence that can be beneficial, neutral, or harmful.

Evolution

• Natural Selection: Mechanism of evolution where individuals with advantageous traits survive and reproduce.
• Speciation: Process by which new species arise.
• Evidence for Evolution:
  • Fossil records.
  • Comparative anatomy (homologous and analogous structures).
  • Genetic similarities among species.

Ecology

• Ecosystems: Interactions between organisms and their environment.
• Biomes: Major ecological community types (e.g., rainforest, desert).
• Food Chains and Webs: Energy flow through trophic levels (producers, consumers, decomposers).
• Population Dynamics: Factors affecting population size (birth rate, death rate, immigration, emigration).

Physiology

• Homeostasis: Maintaining internal balance (temperature, pH, etc.).
• Organ Systems:
  • Circulatory: Transports nutrients and oxygen.
  • Respiratory: Gas exchange.
  • Digestive: Breaks down food for energy.
  • Nervous: Receives and processes information.
  • Endocrine: Hormone regulation and control.

Plant Biology

• Photosynthesis: Conversion of light energy into chemical energy (glucose) using sunlight, CO2, and H2O.

• Plant Structure:

  • Roots: Anchor plants and absorb water/nutrients.
  • Stems: Support and transport.
  • Leaves: Main site of photosynthesis.

• Reproduction:

  • Sexual (flowers, seeds).
  • Asexual (cuttings, runners).

Microbiology

• Bacteria: Prokaryotes with diverse metabolic pathways; can be beneficial or pathogenic.
• Viruses: Non-living entities that require a host cell to replicate.
• Fungi: Eukaryotic organisms important for decomposition and nutrient cycling.

Biotechnology

• Genetic Engineering: Manipulation of an organism's DNA (e.g., CRISPR, transgenic organisms).
• Bioremediation: Use of microorganisms to remove pollutants from the environment.
• Cloning: Producing genetically identical organisms.

Human Biology

• Body Systems: Interconnected systems working together (e.g., cardiovascular, respiratory).
• Immune Response: Body's defense mechanisms against pathogens.
• Reproductive System: Mechanisms of human reproduction and development.

Cell Structure and Function

• Prokaryotic cells lack a nucleus, are smaller, and simpler (e.g., bacteria).
• Eukaryotic cells contain a nucleus, are larger, and more complex (e.g., plants, animals).
• The nucleus houses genetic material like DNA.
• Mitochondria serve as energy production sites, generating ATP.
• Ribosomes facilitate protein synthesis.
• Endoplasmic Reticulum (ER) is responsible for synthesizing proteins (rough ER) and lipids (smooth ER).
• The Golgi Apparatus modifies and packages proteins for transport.
• Lysosomes contain enzymes for digesting waste materials.
• Chloroplasts are organelles in plants that conduct photosynthesis, converting sunlight into energy.

Genetics

• DNA is structured as a double helix composed of nucleotides (adenine, thymine, cytosine, guanine).
• Gene expression involves two main processes: transcription (copying DNA to mRNA) and translation (decoding mRNA to synthesize proteins at ribosomes).
• Mendelian genetics involves dominant and recessive alleles, with Punnett squares used to predict trait inheritance probabilities.
• Mutations are alterations in DNA sequences that can have beneficial, neutral, or harmful effects on an organism.

Evolution

• Natural selection drives evolution by favoring individuals with advantageous traits, leading to greater reproductive success.
• Speciation is the process through which new species evolve from existing ones.
• Evidence for evolution includes fossil records, comparative anatomy (homologous structures indicate common ancestry), and genetic similarities among species.

Ecology

• Ecosystems are formed by interactions between organisms and their physical environment, influencing biodiversity.
• Biomes represent major ecological community types, such as rainforest and desert.
• Food chains and webs illustrate energy flow through various trophic levels: producers (e.g., plants), consumers (e.g., herbivores), and decomposers (e.g., fungi).
• Population dynamics are influenced by factors such as birth rates, death rates, immigration, and emigration.

Physiology

• Homeostasis is the process of maintaining internal balance in factors like temperature and pH.
• The circulatory system is responsible for transporting nutrients and oxygen throughout the body.
• The respiratory system facilitates gas exchange, providing oxygen to the body and removing carbon dioxide.
• The digestive system breaks down food into usable energy products.
• The nervous system processes information and coordinates responses to stimuli.
• The endocrine system regulates processes via hormones, influencing growth, metabolism, and homeostasis.

Plant Biology

• Photosynthesis transforms light energy into chemical energy, producing glucose while using sunlight, carbon dioxide, and water.
• Roots anchor plants and absorb essential nutrients and water.
• Stems provide support to the plant and transport materials between roots and leaves.
• Leaves are primarily responsible for photosynthesis, maximizing light capture.
• Plant reproduction can occur sexually through flowers and seeds or asexually via methods like cuttings or runners.

Microbiology

• Bacteria are prokaryotic organisms with diverse metabolic pathways, some being beneficial (e.g., gut bacteria) while others are pathogenic.
• Viruses are non-living entities requiring a host cell for replication.
• Fungi are eukaryotic organisms vital for decomposition and the cycling of nutrients within ecosystems.

Biotechnology

• Genetic engineering involves manipulating an organism's DNA, utilizing technologies like CRISPR and creating transgenic organisms.
• Bioremediation uses microorganisms to degrade and remove environmental pollutants.
• Cloning enables the production of genetically identical organisms, often used in agriculture and research.

Human Biology

• The human body comprises interconnected systems, including the cardiovascular and respiratory systems, working in unison for overall health.
• The immune response entails various mechanisms to protect the body against pathogens.
• The reproductive system combines processes of human reproduction and development, ensuring species continuation.

Explore the intricate world of cell structure and function, including the differences between prokaryotic and eukaryotic cells. This quiz also covers key concepts in genetics, such as DNA structure, gene expression, and Mendelian inheritance, as well as an introduction to evolution and natural selection.