Connect Synthesis to Cell Function - Biology
- What is dehydration synthesis and which bond does it form between monosaccharides?
- Removal of water to form a glycosidic bond. This process links monosaccharides into larger carbohydrates.
- What is the central dogma that links molecular synthesis to cellular function?
- DNA is transcribed to RNA, and RNA is translated to protein. This fundamental principle describes the flow of genetic information in cells.
- What is the role of rRNA in translation?
- It forms the ribosome and catalyzes peptide bond formation. rRNA is both structural and enzymatic component of ribosomes.
- Which macromolecule class is synthesized for short-term energy storage and cell ID?
- Carbohydrates. These molecules provide quick energy and cellular recognition.
- What is a transcription factor and how does it connect signals to gene expression?
- A regulatory protein that increases or decreases transcription. These proteins regulate gene expression in response to cellular needs.
- What type of bond links amino acids during protein synthesis?
- Peptide bonds. These covalent bonds connect amino acids in the protein backbone.
- What is transcription in terms of molecular synthesis?
- Synthesis of RNA from a DNA template. RNA polymerase reads DNA template to create complementary RNA strand.
- Identify the polysaccharide synthesized for plant cell wall structure.
- Cellulose. This structural polysaccharide provides plant cell rigidity.
- Which organelle modifies, sorts, and packages proteins after synthesis?
- The Golgi apparatus. The Golgi processes proteins after rough ER synthesis.
- What is a gene in the context of molecular synthesis and cellular function?
- A DNA sequence that encodes a functional RNA or protein product. Genes are the basic units of heredity that direct cell functions.
- What is a codon and how does it connect nucleic acid sequence to protein function?
- A 3-base mRNA sequence that specifies an amino acid or stop. The genetic code links DNA sequence to protein amino acid sequence.
- What is phosphorylation and what common effect does it have on proteins?
- Addition of a phosphate group that often changes protein activity. Phosphorylation is a key mechanism for regulating protein function.
- What is a chaperone protein and how does it connect synthesis to function?
- A protein that assists correct folding to achieve functional shape. Chaperones prevent misfolding and ensure proper protein structure.
- What is hydrolysis and what is its effect on polymers in cells?
- Addition of water to break polymers into monomers. This process breaks down macromolecules for cellular use.
- Which macromolecule class is synthesized by dehydration reactions to store genetic info?
- Nucleic acids (DNA and RNA). These polymers store and transmit hereditary information.
- What is the start codon used to initiate translation in most organisms?
- AUG (codes for methionine). This universal start signal ensures proper translation initiation.
- What is the direct product of translation that can affect cell structure and function?
- A polypeptide (protein primary structure). This linear chain of amino acids determines protein folding and function.
- What is the role of tRNA in protein synthesis and cellular function?
- It matches anticodons to codons and delivers amino acids. tRNA serves as the adapter molecule in the genetic code translation.
- Which organelle synthesizes proteins destined for secretion or membranes?
- Ribosomes bound to rough endoplasmic reticulum. The rough ER directs proteins to secretory or membrane pathways.
- What is a signal peptide and what does it determine about a protein's function?
- An amino acid tag that directs a protein to a specific location. Signal sequences target proteins to their proper cellular destinations.
- What is RNA polymerase and what synthesis step does it catalyze?
- An enzyme that synthesizes RNA during transcription. This enzyme catalyzes the formation of RNA from DNA template.
- What is the role of mRNA in connecting gene sequence to cell function?
- It carries the coding information from DNA to ribosomes. mRNA acts as a messenger between nuclear DNA and cytoplasmic ribosomes.
- Which macromolecule class is synthesized to form membranes and influence transport?
- Lipids (especially phospholipids). These molecules create cellular boundaries and compartments.
- What is ATP synthase and what cellular function does it support directly?
- An enzyme that makes ATP, supporting energy-requiring processes. This enzyme is crucial for cellular energy metabolism.
- What is feedback inhibition and how does it connect enzyme function to synthesis?
- An end product inhibits an early enzyme to regulate pathway output. This mechanism prevents overproduction of metabolic products.
- What is the function of the 5' cap on eukaryotic mRNA?
- It protects mRNA and helps ribosome binding for translation. The 5' cap is essential for mRNA stability and translation initiation.
- What is the difference between introns and exons in eukaryotic gene expression?
- Introns are removed; exons remain in the mature mRNA. This processing step refines the mRNA before translation.
- What is an operon and what cellular advantage does it provide in prokaryotes?
- A set of genes regulated together for coordinated expression. This allows efficient coordinate regulation of related genes.
- What is an enhancer and what is its effect on molecular synthesis?
- A DNA element that increases transcription when bound by activators. Enhancers can work from distant locations to boost transcription.
- What level of protein structure is determined directly by the amino acid sequence?
- Primary structure. The amino acid sequence directly determines all higher protein structures.
- What is the function of a stop codon in translation?
- It signals termination of translation and release of the polypeptide. UAA, UAG, and UGA codons halt translation when reached.
- What is the function of the poly-A tail on eukaryotic mRNA?
- It increases mRNA stability and supports translation efficiency. The poly-A tail enhances mRNA lifespan and translation rate.
- Identify the molecule synthesized to store energy long-term in many animals.
- Triglycerides (fats). These lipids store more energy per gram than carbohydrates.
- Identify the polysaccharide synthesized for energy storage in plants.
- Starch. Plants synthesize starch in chloroplasts and amyloplasts.
- Which base in RNA replaces thymine and how does that affect transcription products?
- Uracil (U) replaces thymine (T) in RNA. This base-pairing difference distinguishes RNA from DNA structure.
- What is ubiquitination and what cellular process does it commonly trigger?
- Protein tagging that targets proteins for proteasome degradation. This modification marks proteins for controlled degradation.
- Identify the polysaccharide synthesized for energy storage in animals.
- Glycogen. Animals store glycogen primarily in liver and muscle.
- What is the main cellular consequence of a change in a protein's amino acid sequence?
- Altered folding and function, potentially changing cell phenotype. Protein shape changes can disrupt enzyme activity or binding.
- Which macromolecule class is synthesized to provide structure and catalysis?
- Proteins. Proteins perform most cellular work including catalysis and structure.
- What is a membrane protein and what is one core cellular role it can perform?
- A protein in the lipid bilayer that mediates transport or signaling. These proteins control what enters and exits the cell.
- What is an enzyme and how does its synthesis affect cellular metabolism?
- A biological catalyst; more enzyme can increase pathway rate. Enzyme concentration directly affects metabolic pathway rates.
- What is alternative splicing and how can it change cellular function?
- Different exon combinations produce different proteins from one gene. This process increases protein diversity from a single gene.
- What is the main function of cholesterol in animal cell membranes?
- It modulates membrane fluidity and stability. Cholesterol helps maintain optimal membrane properties.
- What is post-translational modification and why does it matter for cell function?
- Chemical changes to proteins that regulate activity, location, or stability. These modifications fine-tune protein activity after synthesis.
- What is the function of the lac operon when lactose is present?
- It induces enzymes needed to import and metabolize lactose. The lac operon enables bacteria to respond to lactose availability.
- Which option best connects a DNA mutation to altered cell function: silent, missense, or nonsense mutation?
- Nonsense mutation (introduces a premature stop codon). Nonsense mutations create truncated, usually nonfunctional proteins.
- Which organelle is the primary site of protein synthesis for cytosolic proteins?
- Free ribosomes in the cytosol. These ribosomes make proteins that function within the cytoplasm.
- What is a promoter and how does it influence cellular function?
- A DNA region where RNA polymerase binds to start transcription. Promoters control when and how much RNA is transcribed.
- What is the primary function of ribosomes in all cells?
- Protein synthesis by translation. Ribosomes are the universal protein-making machines of cells.
- What is translation in terms of molecular synthesis?
- Synthesis of a polypeptide using an mRNA template. Ribosomes decode mRNA codons to assemble amino acids into proteins.