Cell Structure and Functions Quiz

Hydrogen bonds connect complementary base pairs, stabilizing the double helix structure.

The antiparallel nature allows for proper alignment of hydrogen bonds between the base pairs.

Chargaff observed that the proportions of adenine to thymine and guanine to cytosine are equal.

<p>It illustrates the complexity of sorting and evenly distributing DNA during cell division.</p> Signup and view all the answers

<p>Helicase unwinds the parental double helix.</p> Signup and view all the answers

<p>A gene is a sequence of nucleotides that provides instructions for synthesizing a specific protein.</p> Signup and view all the answers

<p>The leading strand is synthesized continuously, while the lagging strand is synthesized discontinuously.</p> Signup and view all the answers

<p>The DNA backbone consists of alternating sugar and phosphate molecules.</p> Signup and view all the answers

<p>Even separation is critical to avoid DNA loss, which can lead to severe genetic disorders.</p> Signup and view all the answers

<p>Single-strand binding proteins stabilize the unwound parental DNA.</p> Signup and view all the answers

<p>The double helix is like a twisted ladder, with base pairs as rungs and the sugar-phosphate backbone as the sides.</p> Signup and view all the answers

<p>A short RNA primer is synthesized by primase.</p> Signup and view all the answers

<p>The leading strand is synthesized in the 5' to 3' direction.</p> Signup and view all the answers

<p>The RNA primer provides a starting point for DNA polymerase during replication.</p> Signup and view all the answers

<p>DNA undergoes semiconservative replication, meaning each new DNA molecule contains one original and one newly synthesized strand.</p> Signup and view all the answers

<p>Receptor proteins bind to hormones and transport molecules, facilitating their entry and exit from cells.</p> Signup and view all the answers

<p>mRNA is transcribed from DNA and serves as a template during translation to synthesize proteins.</p> Signup and view all the answers

<p>Transcription copies genes from DNA into mRNA, allowing the genetic information to be expressed as proteins.</p> Signup and view all the answers

<p>Transcription involves copying only segments of DNA into RNA, while replication copies the entire DNA molecule.</p> Signup and view all the answers

<p>RNA polymerase is the main enzyme that unwinds DNA and synthesizes RNA from the DNA template.</p> Signup and view all the answers

<p>Proteins control the properties and functions of cells, including immunity and cellular processes.</p> Signup and view all the answers

<p>Cells can control gene expression through mechanisms that influence the transcription and translation processes.</p> Signup and view all the answers

<p>The single-stranded nature of RNA allows it to carry genetic information and serve as a template for protein synthesis.</p> Signup and view all the answers

<p>Humans have autosomes and sex chromosomes; autosomes are numbered 1 through 22, while the 23rd pair consists of sex chromosomes (X and Y).</p> Signup and view all the answers

<p>The haploid number refers to the single set of 23 chromosomes found in gametes (egg and sperm cells), essential for sexual reproduction. During fertilization, these haploid cells combine to restore the diploid number of 46 chromosomes in the zygote.</p> Signup and view all the answers

<p>A chromosome consists of two sister chromatids joined together at a region called the centromere. This structure is critical for proper segregation during cell division.</p> Signup and view all the answers

<p>Histones are DNA-binding proteins that help package DNA into chromatin, condensing it into the highly organized structure of chromosomes. This compaction is vital for fitting long DNA strands into cell nuclei.</p> Signup and view all the answers

<p>During cell division, chromatin condenses into highly coiled and tightly packed chromosomes to ensure accurate segregation of genetic material. This process is crucial for maintaining genetic integrity.</p> Signup and view all the answers

<p>Somatic cells contain 46 chromosomes (diploid), while gametes contain 23 chromosomes (haploid). This difference is significant for maintaining chromosome number during reproduction.</p> Signup and view all the answers

<p>Telomeres are the protective ends of chromosomes that prevent degradation and maintain chromosome stability during cell division. They play a role in cellular aging and replication limits.</p> Signup and view all the answers

<p>The size and number of chromosomes vary across species due to differences in evolutionary adaptations, genome organization, and genetic complexity.</p> Signup and view all the answers

<p>The primary purpose of mitosis in somatic cells is to produce two identical daughter cells, each containing an identical copy of the DNA from the original cell.</p> Signup and view all the answers

<p>'Semiconservative' refers to the process of DNA replication where each newly formed DNA molecule consists of one original strand and one newly synthesized strand.</p> Signup and view all the answers

<p>After one complete round of DNA replication, two identical DNA molecules are generated.</p> Signup and view all the answers

<p>Parental DNA strands serve as templates for the synthesis of new DNA strands during replication.</p> Signup and view all the answers

<p>Prior to replication, the nucleotide strands in a DNA molecule are separated to allow access for the synthesis of new strands.</p> Signup and view all the answers

<p>The original parent strand is significant because it ensures that the daughter molecules contain the same genetic information as the original DNA.</p> Signup and view all the answers

<p>The newly synthesized strands provide fresh complements to the original strands, resulting in two complete DNA molecules.</p> Signup and view all the answers

<p>The double-helix structure of DNA allows for easy strand separation, enabling each strand to serve as a template for the synthesis of a new complementary strand.</p> Signup and view all the answers

<p>If DNA replication were not semiconservative, cells would produce daughter strands lacking the necessary original genetic information, leading to mutations or cell dysfunction.</p> Signup and view all the answers

<p>Adenine pairing with thymine and cytosine pairing with guanine ensures the accuracy of base pairing during DNA replication, essential for genetic fidelity.</p> Signup and view all the answers

<p>Ribosomes synthesize proteins that are processed within the rough endoplasmic reticulum.</p> Signup and view all the answers

<p>The smooth endoplasmic reticulum is free of ribosomes, while the rough endoplasmic reticulum is studded with them.</p> Signup and view all the answers

<p>Vesicles are responsible for transporting molecules and performing various roles in metabolism.</p> Signup and view all the answers

<p>The nuclear envelope is a double-membrane structure that separates the nucleoplasm from the cytoplasm.</p> Signup and view all the answers

<p>Chromatin is composed of DNA and histone proteins, and it contains genes.</p> Signup and view all the answers

<p>Nucleoli manufacture ribosomal RNA and assemble ribosome subunits.</p> Signup and view all the answers

<p>Chloroplasts are the site of photosynthesis within plant cells.</p> Signup and view all the answers

<p>The central vacuole stores ions, waste products, pigments, and protective compounds.</p> Signup and view all the answers

<p>The nucleus is the largest organelle and acts as the control center for transmitting genetic information.</p> Signup and view all the answers

<p>The smooth endoplasmic reticulum is involved in lipid and steroid synthesis, lipid metabolism, and drug detoxification.</p> Signup and view all the answers