Cell Structure and Genetics Quiz

Cell Types:
- Prokaryotic: No nucleus, smaller, unicellular (e.g., bacteria).
- Eukaryotic: Nucleus present, larger, unicellular or multicellular (e.g., plants, animals).
Cell Organelles:
- Nucleus: Contains genetic material (DNA).
- Mitochondria: Powerhouse of the cell, site of ATP production.
- Ribosomes: Protein synthesis.
- Endoplasmic Reticulum (ER):
  - Rough ER: Studded with ribosomes, synthesizes proteins.
  - Smooth ER: Synthesizes lipids, detoxifies.
- Golgi Apparatus: Modifies, sorts, and packages proteins.
- Lysosomes: Digests waste materials and cellular debris.

DNA Structure:
- Double helix composed of nucleotides (A, T, C, G).
Gene Expression:
- Transcription: DNA to mRNA in the nucleus.
- Translation: mRNA to protein in the cytoplasm.
Mendelian Genetics:
- Dominant and recessive alleles.
- Punnett squares for predicting offspring traits.
- Key concepts: Homozygous, heterozygous, genotype, phenotype.

Natural Selection:
- Mechanism of evolution where organisms better adapted to their environment tend to survive and reproduce.
Speciation:
- Process by which new species arise; can occur through allopatric or sympatric mechanisms.
Evidence of Evolution:
- Fossil records, comparative anatomy, molecular biology, and biogeography.

Ecosystems:
- Composed of living (biotic) and non-living (abiotic) components.
Energy Flow:
- Sunlight → producers (plants) → consumers (herbivores, carnivores) → decomposers.
Biomes:
- Major ecological areas defined by climate, vegetation, and animal life (e.g., tundra, rainforest, desert).

Body Systems:
- Circulatory: Transports blood, nutrients, gases.
- Respiratory: Exchanges gases (O2 and CO2).
- Digestive: Breaks down food, absorbs nutrients.
- Nervous: Processes information, coordinates responses.
Homeostasis:
- The ability of the body to maintain a stable internal environment despite external changes.

Bacteria:
- Single-celled organisms; can be beneficial (gut flora) or harmful (pathogens).
Viruses:
- Acellular, require a host to replicate; cause various diseases.
Fungi:
- Eukaryotic organisms; decomposers that break down organic matter.

Photosynthesis:
- Process by which plants convert sunlight into chemical energy (glucose).
Plant Structures:
- Roots: Absorb water and nutrients.
- Stems: Support and transport.
- Leaves: Site of photosynthesis.

Innate Behavior:
- Instinctive, genetically programmed (e.g., reflexes).
Learned Behavior:
- Acquired through experience (e.g., conditioning).
Social Behavior:
- Interactions among individuals (e.g., mating, cooperation, competition).

Prokaryotic cells lack a nucleus, are smaller, and primarily unicellular, exemplified by bacteria.
Eukaryotic cells possess a nucleus, are larger, and can be unicellular or multicellular, including plants and animals.
The nucleus houses genetic material (DNA), controlling cell activities.
Mitochondria are known as the cell's powerhouse, responsible for ATP production.
Ribosomes are molecular machines that synthesize proteins.
Rough Endoplasmic Reticulum (ER) has ribosomes, facilitating protein synthesis, while Smooth ER synthesizes lipids and detoxifies substances.
The Golgi Apparatus modifies, sorts, and packages proteins for export.
Lysosomes contain digestive enzymes that break down waste materials and cellular debris.

DNA is structured as a double helix, formed by nucleotides: adenine (A), thymine (T), cytosine (C), and guanine (G).
Transcription converts DNA into messenger RNA (mRNA) in the nucleus, while translation occurs in the cytoplasm, turning mRNA into proteins.
Mendelian genetics explains inheritance patterns, focusing on dominant and recessive alleles.
Punnett squares aid in predicting traits of offspring, distinguishing between homozygous and heterozygous genotypes and phenotypes.

Natural selection drives evolution, allowing organisms better suited to their environment to survive and reproduce.
Speciation, the development of new species, can occur through allopatric (geographical separation) or sympatric (same area) mechanisms.
Evidence of evolution includes fossil records, comparative anatomy, molecular biology, and biogeographical patterns.

Ecosystems consist of biotic (living) and abiotic (non-living) elements interacting within an environment.
Energy flow in ecosystems typically follows a route from sunlight to producers (like plants), then to consumers (herbivores, carnivores), and finally to decomposers.
Biomes are vast ecological regions defined by distinct climates, vegetation types, and animal species, such as tundras, rainforests, and deserts.

The circulatory system's primary function is to transport blood, nutrients, and gases throughout the body.
The respiratory system facilitates gas exchange, mainly oxygen (O2) for carbon dioxide (CO2).
The digestive system breaks down food and absorbs essential nutrients.
The nervous system processes information and coordinates bodily responses to stimuli.
Homeostasis is the body’s ability to maintain stable internal conditions despite external fluctuations.

Bacteria are single-celled organisms that can have beneficial roles (e.g., gut flora) or harmful effects as pathogens.
Viruses are acellular entities that require a host to replicate and can cause a variety of diseases.
Fungi are eukaryotic organisms that act as decomposers, breaking down organic matter for nutrient recycling.

Photosynthesis is the process by which plants convert sunlight into chemical energy in the form of glucose.
Key plant structures include roots for water and nutrients absorption, stems for support and transport, and leaves where photosynthesis takes place.

Innate behavior is instinctual and genetically driven, like reflexive actions.
Learned behavior is developed through experience, such as conditioning.
Social behavior encompasses interactions among individuals, manifesting in mating rituals, cooperation, and competition.