Geomagnetic Map Sense

Free to try, no login

In the text below some words are missing. Drag words from the box below to the appropriate place in the text. There are more words than you need.

Hatchling sea turtles rely on an inherited geomagnetic map to navigate vast oceanic gyres. By detecting variations in magnetic and inclination angle, individuals can deduce their approximate geographic position. Laboratory experiments indicate that exposure to simulated fields triggers directed swimming responses, allowing juveniles to remain within favourable currents. This internal compass prevents drift into dangerously cold waters, ensuring long-term throughout early developmental stages.

Drag a word into a gap, or tap a word and then a gap. Tap a filled gap to empty it.

Questions 2–5

In the text below some words are missing. Drag words from the box below to the appropriate place in the text. There are more words than you need.

Read them here; log in to answer and check them.

Wave Cue Orientation

Upon entering the surf zone, neonatal turtles must quickly establish an offshore trajectory. Visual cues become unreliable in turbulent water, prompting hatchlings to orient into oncoming waves. By monitoring acceleration patterns and physical 1, they maintain a perpendicular path relative to the shoreline. This mechanical orientation functions as a vital 2 mechanism, guiding individuals past predatory coastal waters before broader regional navigation systems become fully 3.

barriers
forces
reversed
operational
transition
sensory

Olfactory Imprinting and Homing

Natal homing in adult female sea turtles involves a sophisticated combination of sensory inputs. While geomagnetic data provides regional guidance, chemical signatures are thought to facilitate the final 1 of specific nesting beaches. Hatchlings likely absorb distinctive airborne and dissolved compounds, establishing an olfactory memory that remains 2 for decades. When mature females prepare to reproduce, these stored chemical cues help them 3 their birthplace with remarkable accuracy.

pinpoint
identification
erratic
accelerate
emission
dormant

Seaward Visual Guidance

Immediately after emerging from subterranean nests at night, hatchlings must rapidly locate the sea. They naturally head towards the lowest, brightest horizon, relying on the natural 1 of starlight and moonlight on open water. However, artificial coastal illumination can 2 this visual orientation, drawing young turtles inland towards dehydration and traffic. Effective conservation strategies often include shielding beachfront fixtures to restore natural visual cues and ensure 3 seaward movement.

absorption
unhindered
reflectance
sporadic
sustain
disrupt

Pelagic Dispersal and Drift

Young loggerhead turtles spending their developmental years in the open ocean do not simply drift as passive particles. Although powerful oceanic currents dictate their general 1, tracking devices show that turtles actively swim to correct their course. By modifying their swimming effort, individuals avoid lethal oceanic boundaries and exploit nutrient-rich 2 zones. This interaction between passive transport and directed locomotion produces a finely tuned dispersal 3 across thousands of kilometres.

hesitation
frontal
interior
strategy
momentum
trajectory

Want to answer the other 4?

Log in to practise Reading: Fill in the Blanks in the BandLadder app: the full question bank, instant scoring the way Pearson marks it, and answer explanations.

Ready for the whole test?

Take a full PTE mock with every question type, the real timings and a score on Pearson's 10–90 scale the moment you finish.

Try a free PTE mock →

Keep practising

Sea Turtle Oceanic Navigation