Unit 12: Genetics and athletic performance

Question 1

Outline the role of genes in the inheritance of human characteristics (6)

Answer 1

1. CHROMOSOMES are made of DNA sections of which are referred to as GENES.
2. DNA undergoes REPLICATION (copy exactly) as part of CELL DIVISION to pass on the genes to new cells.
3. Children inherit genes from their parents via the sex cells (gametes) (50/50 ratio). Millions of different combinations of these genes from the same parents are possible.
4. GENOTYPE: their genes
5. PHENOTYPE: human characteristics
6. Some characteristics are expressed developmentally by…
   - genes (eye color, gender)
   - environmental switch (height, VO2max).

Question 2

Outline how genes can influence human characteristics (3)

Answer 2

1. PROTEIN PRODUCTION: Genes code for the production of proteins, which are responsible for the development of an individual.
2. GENES SWITCHED OFF AND ON: Genes can be switched on or switched off depending on internal or external factors, so that characteristics influencing athletic performance can change during a person’s lifetime.

3.

Question 3

Discuss the relative contribution of genetic and environmental factors on performance in different sports

Answer 3

Characteristics influenced by genetics…
1. height
2. muscle fibre type
3. anaerobic threshold
4. lung capacity
5. flexibility.

Environmental factors that also influence performance…
1. physical training
2. nutrition
3. technological aids
4. climate.

Question 4

How are elite athletes distinguished from other ahtletes according to genetics?

Answer 4

Training maximizes the likelihood of obtaining a performance level with a genetically controlled ceiling.
Elite athletes can be distinguished from less well-performing athletes with respect to both inherited (genetic) characteristics and training histories.

Question 5

Discuss the implications of genetic screening for sports, exercise and health (5)

Answer 5

POSITIVE:
1. Identification of LIFE-THREATENING CONDITIONS (ex. risk of sudden cardiac death)
2. Potential to PREDICT SUSCEPTIBILITY to injury and so reduce risk for an individual athlete

NEGATIVE:
1. Involuntary exclusion/discrimination in sports
2. Discrimination beyond sport, ex. employment
3. Increase possibility of gene doping in the future to improve athletic performance