Cell Structure and Function Quiz

Cell Structure and Function

• Cell Types

  • Prokaryotic: No nucleus, smaller, e.g., bacteria.
  • Eukaryotic: Nucleus present, larger, e.g., plants, animals.

• Cell Organelles

  • Nucleus: Controls cell activities, contains DNA.
  • Mitochondria: Powerhouse of the cell, energy production via respiration.
  • Ribosomes: Protein synthesis.
  • Endoplasmic Reticulum (ER):
    • Rough ER: Studded with ribosomes, synthesizes proteins.
    • Smooth ER: Lacks ribosomes, synthesizes lipids.
  • Golgi Apparatus: Modifies, sorts, and packages proteins.
  • Lysosomes: Digests waste materials and cellular debris.
  • Cell Membrane: Semi-permeable barrier, regulates entry/exit of substances.

Genetics

• DNA Structure

  • Double helix composed of nucleotides (A, T, C, G).
  • Base pairing: Adenine pairs with Thymine; Cytosine pairs with Guanine.

• Gene Expression

  • Transcription: DNA to mRNA in the nucleus.
  • Translation: mRNA to protein in the cytoplasm.

• Mendelian Genetics

  • Genes: Units of heredity.
  • Alleles: Different forms of a gene.
  • Dominant and Recessive traits: Dominant alleles mask recessive traits.

Evolution

• Natural Selection

  • Mechanism of evolution proposed by Darwin.
  • Organisms better adapted to environment tend to survive and reproduce.

• Speciation

  • Process by which new species arise.
  • Can occur through geographic isolation or reproductive isolation.

Ecology

• Ecosystems

  • Composed of biotic (living) and abiotic (non-living) components.
  • Energy flow: From producers (plants) to consumers (herbivores, carnivores).

• Biomes

  • Major ecological zones characterized by climate and vegetation, e.g., tundra, rainforest, desert.

• Trophic Levels

  • Primary producers: Autotrophs (plants).
  • Primary consumers: Herbivores.
  • Secondary consumers: Carnivores that eat herbivores.
  • Tertiary consumers: Carnivores that eat other carnivores.

Human Biology

• Body Systems

  • Circulatory: Transports blood, nutrients, gases.
  • Respiratory: Gas exchange (oxygen and carbon dioxide).
  • Digestive: Breaks down food, absorbs nutrients.
  • Nervous: Controls body functions and responds to stimuli.

• Homeostasis

  • Maintenance of a stable internal environment (temperature, pH, etc.).

Plant Biology

• Photosynthesis

  • Process by which plants convert sunlight into chemical energy (glucose).
  • Equation: 6CO2 + 6H2O + light energy → C6H12O6 + 6O2.

• Plant Structures

  • Roots: Anchor plant, absorb water and nutrients.
  • Stems: Support plant, transport nutrients and water.
  • Leaves: Main site for photosynthesis.

Microbiology

• Bacteria

  • Prokaryotic organisms, can be beneficial (gut flora) or pathogenic (cause disease).

• Viruses

  • Non-cellular, require a host to replicate, can cause infections.

• Fungi

  • Eukaryotic organisms, decomposers, can be unicellular (yeast) or multicellular (mushrooms).

Cell Structure and Function

• Prokaryotic cells lack a nucleus and are generally smaller than eukaryotic cells; examples include bacteria.
• Eukaryotic cells contain a nucleus and are larger; examples include plants and animals.
• The nucleus regulates cell activities and houses the cell's DNA.
• Mitochondria are known as the cell's powerhouse, generating energy through respiration.
• Ribosomes are essential for synthesizing proteins.
• The rough endoplasmic reticulum (ER) has ribosomes on its surface and synthesizes proteins, while the smooth ER synthesizes lipids.
• The Golgi apparatus modifies, sorts, and packages proteins for transport.
• Lysosomes function to digest waste materials and breakdown cellular debris.
• The cell membrane serves as a semi-permeable barrier, controlling the movement of substances in and out of the cell.

Genetics

• DNA is structured as a double helix, composed of nucleotides containing adenine (A), thymine (T), cytosine (C), and guanine (G).
• Base pairing rules dictate that adenine pairs with thymine and cytosine pairs with guanine.
• Transcription is the process of converting DNA into messenger RNA (mRNA) in the nucleus.
• Translation occurs in the cytoplasm, where mRNA is translated into proteins.
• Genes are the fundamental units of heredity while alleles represent different forms of a gene.
• Dominant alleles express traits that can mask the effects of recessive alleles.

Evolution

• Natural selection, a concept formulated by Charles Darwin, is the process through which organisms best suited to their environment are more likely to survive and reproduce.
• Speciation is the formation of new and distinct species, which can occur via geographic or reproductive isolation.

Ecology

• Ecosystems consist of biotic (living organisms) and abiotic (non-living environmental factors) components.
• Energy transfer within ecosystems starts with producers (plants) and flows to various levels of consumers including herbivores and carnivores.
• Biomes represent large ecological areas defined by distinct climates and vegetation types, such as tundra, rainforest, and desert.
• Trophic levels organize organisms based on their feeding relationships: primary producers (plants), primary consumers (herbivores), secondary consumers (carnivores that eat herbivores), and tertiary consumers (carnivores that eat other carnivores).

Human Biology

• The circulatory system is responsible for blood transport along with nutrients and gases throughout the body.
• The respiratory system facilitates gas exchange, supplying oxygen to the body while removing carbon dioxide.
• The digestive system processes food and absorbs essential nutrients.
• The nervous system manages body responses and controls various functions.
• Homeostasis is crucial for maintaining a stable internal environment, encompassing temperature and pH balance.

Plant Biology

• Photosynthesis allows plants to convert light energy into chemical energy (glucose) using the formula: 6CO2 + 6H2O + light energy → C6H12O6 + 6O2.
• Roots secure plants in place and absorb both water and essential nutrients from the soil.
• Stems provide structural support and transport nutrients and water throughout the plant.
• Leaves are predominantly responsible for photosynthesis, as they contain chlorophyll for capturing light energy.

Microbiology

• Bacteria are prokaryotic organisms that can be beneficial, such as gut flora, or pathogenic, causing various diseases.
• Viruses, which lack cellular structure, require a host organism for replication and can lead to infections in the host.
• Fungi are eukaryotic organisms that function as decomposers in ecosystems, existing in unicellular forms like yeast or multicellular forms such as mushrooms.

Test your knowledge on cell types, organelles, and genetic concepts. This quiz covers prokaryotic and eukaryotic cells, as well as DNA structure and gene expression. Ideal for biology students looking to reinforce their understanding of cellular components and genetics.