Photo AI
3.1 The diagrams below show the skulls of two species of primates - NSC Life Sciences - Question 3 - 2019 - Paper 2
Question 3
3.1 The diagrams below show the skulls of two species of primates. Skull 1 Skull 2 3.1.1 Tabulate THREE observable differences between sk... show full transcript
Worked Solution & Example Answer:3.1 The diagrams below show the skulls of two species of primates - NSC Life Sciences - Question 3 - 2019 - Paper 2
Step 1
Step 2
3.1.2 Give FOUR characteristics of the upper limbs that humans share with other primates.
Answer
- Freely rotating arms: This allows a wide range of motion for various activities.
- Long upper arms: Proportionally longer arms assist in reaching and manipulation.
- Rotation around elbow joints: Enables diverse movements for carrying and using tools.
- Opposable thumbs: Essential for gripping and manipulating objects effectively.
Step 3
3.1.3 Explain how an increase in cranial volume is related to intelligence.
Answer
An increase in cranial volume typically indicates a larger brain size, which houses more neurons. A larger number of neurons can enhance cognitive abilities, including memory, problem-solving, and complex reasoning. Research suggests that a significant relationship exists between brain volume and intellectual capacity, with larger brains generally correlating with higher intelligence.
Step 4
Step 5
3.2.2 Explain how each of the following skeletal structures have contributed to bipedalism in humans:
Answer
(a) Foramen magnum: The foramen magnum is positioned beneath the skull, which allows the spinal cord to enter vertically and supports a more upright posture.
(b) Pelvic girdle: The pelvic girdle is short and broad, facilitating balance and weight distribution while upright, and supports the body’s weight during movement.
(c) Spine: The spine has an S-shaped curve, which absorbs shock and allows for flexible movement, aiding bipedal locomotion.
Step 6
3.3 Describe the process of speciation through geographical isolation.
Answer
Speciation through geographical isolation occurs when a population of a species is separated by a physical barrier, such as a mountain range or river. This prevents gene flow between the separated groups. Over time, natural selection and genetic drift can lead to divergent evolution, as each group adapts to its unique environment. Eventually, the genetic differences may become significant enough that even if the populations come into contact again, they can no longer interbreed, resulting in the emergence of new species.
Step 7
Step 8
3.4.2 Give evidence in the extract which suggests that the survival of people living at high altitudes could be:
Answer
(a) Due to a genetically inherited trait: The mutant gene that enables more efficient oxygen use is inherited from ancestors.
(b) Caused by an environmental factor: The low oxygen levels found at high altitude require adaptations for survival.
Step 9
3.4.3 Describe how Lamarck would explain the survival of Tibetans at high altitude.
Answer
Lamarck might argue that the survival of Tibetans at high altitudes is due to the inheritance of acquired characteristics. He could posit that ancestors who adapted to low oxygen environments developed traits (such as an increased production of red blood cells) that were then passed down to their offspring, enhancing their survival in such conditions.