3.4.7 Investigating diversity

Which of the following is NOT a method used to compare genetic diversity within or between species?

• Comparing the base sequence of DNA

• Comparing the base sequence of mRNA

• Comparing the amino acid sequence of proteins

• Comparing the boiling point of water in different organisms

Answer explanation

Comparing the boiling point of water in different organisms is not a method for assessing genetic diversity. The other options involve direct genetic or protein comparisons, which are relevant for studying genetic variation.

What can be inferred by comparing the base sequences of DNA between two organisms?

• Their relationship within or between species

• Their body temperature

• Their habitat preference

• Their average lifespan

Answer explanation

Comparing DNA base sequences reveals genetic similarities and differences, which helps infer evolutionary relationships between organisms, making 'their relationship within or between species' the correct choice.

Which of the following has replaced the use of observable characteristics in investigating genetic diversity?

• Direct investigation of DNA sequences

• Measuring body mass

• Observing fur colour

• Counting the number of offspring

Answer explanation

The correct choice, 'Direct investigation of DNA sequences', has replaced observable characteristics like fur color and body mass in studying genetic diversity, providing more precise genetic information.

Why is comparing the amino acid sequence of proteins useful in studying genetic diversity?

• It reflects differences in the underlying DNA and mRNA sequences

• It shows the organism's diet

• It determines the organism's age

• It measures the organism's height

Answer explanation

Comparing amino acid sequences reveals variations that stem from differences in the DNA and mRNA sequences. This helps in understanding genetic diversity among organisms.

Which of the following statements is TRUE regarding gene technology and genetic diversity?

• Gene technology has made it possible to directly compare DNA sequences

• Gene technology has made observable characteristics more important

• Gene technology is only used for cloning

• Gene technology cannot be used to study mRNA

Answer explanation

The correct statement is that gene technology has enabled direct comparison of DNA sequences, facilitating studies on genetic diversity. The other options are incorrect as they misrepresent the capabilities of gene technology.

What is the main advantage of using DNA base sequence comparison over observable characteristics in studying genetic diversity?

• It provides more direct and accurate information about genetic differences

• It is less expensive

• It requires no laboratory equipment

• It is based on physical appearance

Answer explanation

The main advantage of using DNA base sequence comparison is that it provides more direct and accurate information about genetic differences, unlike observable characteristics which can be influenced by environmental factors.

Which of the following is a measurable or observable characteristic that was traditionally used to infer genetic diversity?

• Flower colour in plants

• DNA base sequence

• mRNA base sequence

• Amino acid sequence

Answer explanation

Flower colour in plants is a visible trait that has been used to assess genetic diversity, making it a measurable characteristic. In contrast, DNA, mRNA, and amino acid sequences are not directly observable traits.

Interpreting data on which of the following can help suggest relationships between different organisms?

• Base sequences of DNA and amino acid sequences of proteins

• The number of leaves on a plant

• The amount of water an animal drinks

• The length of an animal's tail

Answer explanation

Base sequences of DNA and amino acid sequences of proteins provide insights into genetic relationships and evolutionary connections between organisms, making them crucial for understanding biological relationships.

Which molecule's base sequence can be compared to study genetic diversity, apart from DNA?

• mRNA

• Glucose

• ATP

• Cellulose

Answer explanation

mRNA, or messenger RNA, carries the genetic information from DNA and can be sequenced to study genetic diversity. Unlike glucose, ATP, and cellulose, mRNA's base sequence is directly related to gene expression and variation.

What has gene technology changed in the study of genetic diversity?

• It has shifted the focus from observable characteristics to direct DNA analysis

• It has made observable characteristics more reliable

• It has eliminated the need for laboratory work

• It has made genetic diversity studies obsolete

Answer explanation

Gene technology has revolutionized the study of genetic diversity by enabling direct DNA analysis, moving away from reliance on observable traits, which can be misleading. This shift allows for more accurate assessments of genetic variation.