Year 10 Biology: DNA all the way

Flashcards for reviewing key biology concepts related to DNA, genetics, and reproduction.

What is a genome?

The complete set of genetic material in an organism.

What is a gene?

A specific sequence of DNA that codes for a particular trait.

What is an allele?

A variant form of a gene.

What are the names of the 4 (5) bases in DNA and RNA?

Adenine, Thymine, Guanine, Cytosine. RNA also has Uracil.

How does DNA get packaged into chromosomes?

DNA is tightly coiled and packaged around proteins called histones.

Do prokaryotes have chromosomes?

No, prokaryotes have a single, circular chromosome.

What is a karyotype and what is it useful for?

A display of chromosomes, useful for detecting chromosomal abnormalities.

Why do cells replicate?

For growth, repair, and reproduction.

Why do cells grow?

Cells grow to increase in size and complexity, but need to divide before they become too large.

What is the process of replication for Eukaryotes and how/why is it different to replication in prokaryotes?

Eukaryotic replication is more complex due to larger genome size and linear chromosomes.

Why are there stages to the cell cycle?

To ensure proper DNA replication, error correction, and cell division.

What happens at each stage of the cell cycle?

G1 (growth), S (DNA replication), G2 (preparation for mitosis), Mitosis (cell division).

How are the stages of the cell cycle different from those of mitosis?

Mitosis focuses on nuclear division, while the cell cycle includes interphase (G1, S, G2).

What are the products of mitosis and meiosis and what are they used for?

Mitosis produces two identical daughter cells, while meiosis produces four genetically different haploid cells.

Explain the changes in chromosome number at each stage of mitosis.

Chromosome number remains the same in mitosis, while it is halved in meiosis.

Describe at least three different types of asexual reproduction.

Fission, budding, vegetative propagation, cloning.

What is the difference between somatic and gametic cells? Where are both cell types found in people?

Somatic cells are body cells; gametic cells are sex cells (sperm and egg).

Why are gametes required for the production of the next generation? What is the importance of having two cycles of cell division?

Gametes are required to provide genetic variation and maintain the correct chromosome number in offspring. Meiosis ensures genetic diversity.

Explain the meanings of the words genotype and phenotype. How are they different?

Genotype is the genetic makeup; phenotype is the physical expression of the genes.

Why can we see variation within families and populations?

Variation arises from genetic recombination during sexual reproduction, mutations, and environmental factors.

What are patterns of inheritance?

Patterns of inheritance like autosomal dominant/recessive, sex-linked, and multiple alleles.

How to construct Punnett squares to show autosomal and sex-linked conditions?

Use Punnett squares to predict the probability of offspring genotypes and phenotypes for autosomal and sex-linked conditions.

How would a chart show an autosomal dominant, autosomal recessive, or sex (x) linked recessive condition?

Pedigree charts show inheritance patterns of genetic conditions through generations.

What are the similarities and differences between an affected individual and a carrier?

Affected individuals show the trait; carriers have the allele but don't show the trait.

What is a species?

A group of organisms that can interbreed and produce fertile offspring.

Why would new species evolve?

New species evolve due to natural selection, genetic drift, and reproductive isolation.

Is natural selection part of survival of the fittest, or is survival of the fittest part of natural selection?

Natural selection is the process where organisms with advantageous traits are more likely to survive and reproduce (survival of the fittest is part of this).

Explain how we are related to primates?

We share a common ancestor with primates.

Is it correct to say that 'we descended from monkeys'?

No, we share a common ancestor with monkeys; we didn't descend directly from modern monkeys.

What is a genome?

The complete set of genetic material in an organism.

What is a gene?

A specific sequence of DNA that codes for a particular trait.

What is an allele?

A variant form of a gene.

What are the names of the 4 (5) bases in DNA and RNA?

Adenine, Thymine, Guanine, Cytosine. RNA also has Uracil.

How does DNA get packaged into chromosomes?

DNA is tightly coiled and packaged around proteins called histones.

Do prokaryotes have chromosomes?

No, prokaryotes have a single, circular chromosome.

What is a karyotype and what is it useful for?

A display of chromosomes, useful for detecting chromosomal abnormalities.

Why do cells replicate?

For growth, repair, and reproduction.

Why do cells grow?

Cells grow to increase in size and complexity, but need to divide before they become too large.

What is the process of replication for Eukaryotes and how/why is it different to replication in prokaryotes?

Eukaryotic replication is more complex due to larger genome size and linear chromosomes.

Why are there stages to the cell cycle?

To ensure proper DNA replication, error correction, and cell division.

What happens at each stage of the cell cycle?

G1 (growth), S (DNA replication), G2 (preparation for mitosis), Mitosis (cell division).

How are the stages of the cell cycle different from those of mitosis?

Mitosis focuses on nuclear division, while the cell cycle includes interphase (G1, S, G2).

What are the products of mitosis and meiosis and what are they used for?

Mitosis produces two identical daughter cells, while meiosis produces four genetically different haploid cells.

Explain the changes in chromosome number at each stage of mitosis.

Chromosome number remains the same in mitosis, while it is halved in meiosis.

Describe at least three different types of asexual reproduction.

Fission, budding, vegetative propagation, cloning.

What is the difference between somatic and gametic cells? Where are both cell types found in people?

Somatic cells are body cells; gametic cells are sex cells (sperm and egg).

Why are gametes required for the production of the next generation? What is the importance of having two cycles of cell division?

Gametes are required to provide genetic variation and maintain the correct chromosome number in offspring. Meiosis ensures genetic diversity.

Explain the meanings of the words genotype and phenotype. How are they different?

Genotype is the genetic makeup; phenotype is the physical expression of the genes.

Why can we see variation within families and populations?

Variation arises from genetic recombination during sexual reproduction, mutations, and environmental factors.

What are patterns of inheritance?

Patterns of inheritance like autosomal dominant/recessive, sex-linked, and multiple alleles.

How to construct Punnett squares to show autosomal and sex-linked conditions?

Use Punnett squares to predict the probability of offspring genotypes and phenotypes for autosomal and sex-linked conditions.

How would a chart show an autosomal dominant, autosomal recessive, or sex (x) linked recessive condition?

Pedigree charts show inheritance patterns of genetic conditions through generations.

What are the similarities and differences between an affected individual and a carrier?

Affected individuals show the trait; carriers have the allele but don't show the trait.

What is a species?

A group of organisms that can interbreed and produce fertile offspring.

Why would new species evolve?

New species evolve due to natural selection, genetic drift, and reproductive isolation.

Is natural selection part of survival of the fittest, or is survival of the fittest part of natural selection?

Natural selection is the process where organisms with advantageous traits are more likely to survive and reproduce (survival of the fittest is part of this).

Explain how we are related to primates?

We share a common ancestor with primates.

Is it correct to say that 'we descended from monkeys'?

No, we share a common ancestor with monkeys; we didn't descend directly from modern monkeys.

What are the key differences between DNA and RNA?

DNA is double-stranded and contains deoxyribose sugar and thymine (T), while RNA is single-stranded, contains ribose sugar, and uracil (U).

What are the main types of RNA and their functions?

mRNA (messenger RNA) carries genetic information from DNA to ribosomes, tRNA (transfer RNA) brings amino acids to the ribosome during protein synthesis, and rRNA (ribosomal RNA) is a component of ribosomes.

Describe the process of transcription.

Transcription is the process where RNA polymerase synthesizes an RNA molecule from a DNA template.

Describe the process of translation.

Translation is the process where ribosomes use mRNA to synthesize proteins with the help of tRNA.

What is the role of ribosomes in protein synthesis?

Ribosomes are the sites of protein synthesis, where mRNA is decoded, and tRNA brings the correct amino acids to build the polypeptide chain.

What are codons and anticodons?

Codons are sequences of three nucleotides in mRNA that specify a particular amino acid, while anticodons are complementary sequences on tRNA that

What are the steps of DNA packaging?

1. DNA double helix: DNA starts as a double-stranded helix. 2. Nucleosome formation: DNA wraps around histone proteins to form nucleosomes. 3. Chromatin fiber: Nucleosomes coil to form a chromatin fiber. 4. Loops: The chromatin fiber forms loops attached to a protein scaffold. 5. Chromosome: During cell division, these loops further condense and coil to form a visible chromosome.