Question

For each species, all ________in the complete set of chromosomes is the___________. a. mutations; DNA profile b. DNA; genome c. SNPs; genome d. genomes; genotype

Short answer

The correct answer is b: 'DNA; genome'.

Step-by-step solution

Identify the Task

This is a multiple-choice question that asks about a specific vocabulary term used in genetics. You must fill in the blanks with the correct terms from the provided options.

Analyze the Sentence Structure

The sentence to complete states: 'For each species, all ________ in the complete set of chromosomes is the ___________.' This suggests a definition or characteristic of a genetic term.

Option a Examined

Option a is 'mutations; DNA profile'. The sentence would read: 'For each species, all mutations in the complete set of chromosomes is the DNA profile.' Mutations are not what describe a complete set of chromosomes.

Option b Examined

Option b is 'DNA; genome'. The sentence would read: 'For each species, all DNA in the complete set of chromosomes is the genome.' This correctly defines the term genome.

Option c Examined

Option c is 'SNPs; genome'. The sentence would read: 'For each species, all SNPs in the complete set of chromosomes is the genome.' While SNPs are part of the genome, they don't constitute the entire genome.

Option d Examined

Option d is 'genomes; genotype'. The sentence would read: 'For each species, all genomes in the complete set of chromosomes is the genotype.' Genomes and genotypes are related but are not interchangeable like this.

Confirm the Answer

The correct fill-in for the blanks, supported by genetic terminology, is found in option b: 'DNA; genome'. This is the most accurate completion of the statement.

Key concepts

DNA

DNA, or deoxyribonucleic acid, is the remarkable molecule that carries the genetic instructions necessary for the growth, development, functioning, and reproduction of all living organisms and many viruses. Comprised of two long strands that coil around each other to form a double helix, this molecular structure contains the instructions an organism needs to develop and function.

The building blocks of DNA are nucleotides, which are made up of a sugar, phosphate group, and a nitrogenous base. The four types of nitrogenous bases are adenine (A), thymine (T), cytosine (C), and guanine (G). These bases are paired specifically (A with T, C with G) to encode the unique genetic information of an organism.

• DNA stores genetic information in the sequence of these bases.
• The information stored in DNA is used to produce proteins, which perform many essential functions in cells.
• DNA replication is the process by which DNA makes a copy of itself during cell division, ensuring that each new cell receives a complete set of genetic information.

Understanding DNA is crucial to comprehending the broader concepts of genetics, as it is fundamentally responsible for the hereditary characteristics of all known living things.

Genome

A genome is the complete set of DNA within an organism, including all of its genes. It is the entirety of the organism's hereditary information. Genomes contain both the coding regions (genes) that direct the synthesis of proteins and the non-coding regions whose functions are often regulatory or unknown.

The study of genomes, called genomics, enables scientists to analyze entire sequences of DNA to understand genetic variation and expression. With advances in technology, many organisms have had their genomes sequenced, leading to immense progress in biotechnology, medicine, and evolutionary biology.

• The human genome, for example, consists of about 3 billion base pairs of DNA and approximately 20,000 to 25,000 genes.
• Understanding an organism's genome can inform everything from diagnosis and treatment of diseases to insights into evolutionary history.
• Genome sequencing projects, such as the human genome project, have revolutionized our ability to study life at a molecular level.

Exploring genomes allows for a deeper grasp of the biological complexities that define every form of life.

Chromosomes

Chromosomes are long, thread-like structures made of protein and a single molecule of DNA, neatly packed to fit into cells. They play a key role in ensuring DNA replication and distribution during cell division. Humans have 23 pairs of chromosomes, each one containing thousands of genes, which are the instructions for growth, development, and functioning.

Each species has a characteristic set of chromosomes that capture the organism's entire genome. The number and structure of chromosomes can vary between individuals within a species, and some conditions, like Down syndrome, are caused by an atypical number of chromosomes.

• During cell division, chromosomes ensure proper distribution of DNA between new cells.
• They contain the genetic instructions that dictate the traits and biological functions of an organism.
• Karyotyping is a technique used to view the number and appearance of chromosomes, often used for diagnosing genetic diseases.

An understanding of chromosomes is fundamental in genetics, as they are essential for the inheritance of traits.

Species

A species is a group of organisms that can interbreed and produce fertile offspring. Defining species is essential for biologists to classify and understand the diversity of life on Earth. Each species has distinct characteristics, and members of the same species share a common genome that represents their particular genetic makeup.

Species are often defined based on their genomic differences, which are crucial for their adaptability and survival in diverse environments. Biodiversity depends heavily on the fact that different species can evolve and adapt over time through natural selection and genetic variation.

• Species classification helps in understanding the natural world and the relationships between different organisms.
• Speciation, the process by which new species come about, is an important concept in evolutionary biology.
• Conservation efforts often focus on preserving species and their habitats to maintain ecological balance.

Grasping what constitutes a species is integral for studying evolution, ecology, and the genetic variation that drives these processes.