Practice Test 16 - High School Biology

20 questions. Answer them in any order, then submit to see your score and every explanation.

Which statement best describes the overall chemical-energy change in cellular respiration (glucose + O2 → CO2 + H2O)?
In a snowy Arctic habitat, rabbits with white fur are less likely to be seen by predators than rabbits with brown fur. In a dark forest habitat, brown fur provides better camouflage than white fur. Which statement best explains how fur color relates to fitness across these environments?
A food chain follows the 10% rule. Producers have 50,000 kcal. Primary consumers have 5,000 kcal. Secondary consumers have 500 kcal. How much energy is lost from primary consumers to secondary consumers?
Two processes are described: Process 1: After a meal, blood glucose rises above normal. The pancreas detects this and releases insulin, causing glucose to be taken up by cells. Blood glucose returns toward normal and insulin release decreases. Process 2: A blood vessel is damaged. Platelets stick to the site and release chemicals that attract more platelets. More platelets arrive and release more chemicals, rapidly building a clot until the wound is sealed. Which option correctly compares how feedback functions in Process 1 vs Process 2?
Fossils from a horse lineage show changes in average shoulder height over millions of years. Time (million years ago): 50, 40, 30, 20, 10, 0 (present) Average shoulder height (m): 0.45, 0.62, 0.88, 1.15, 1.38, 1.50 Which interpretation best matches the trend in the fossil data?
In the model, which component is the main storage location of captured energy before it is used in cellular respiration?
In an ecosystem, green plants convert CO $_2$ into sugars, and animals obtain carbon by eating plants or other animals. Which statement best describes the role of producers in the carbon cycle and food chains?
A population of beetles shows heritable variation in tolerance to a toxin produced by a new invasive plant: some beetles can eat the plant without harm, others become sick and leave fewer offspring. Over several generations in areas where the plant is common, more beetles can tolerate the toxin. Which statement best explains why the population changed?
After a sunburn, many skin cells are damaged and die. Over time, new skin cells appear and the skin returns to normal thickness. Which explanation best describes how cell division and differentiation work together in this repair?
In a population of beetles, color is controlled by two alleles: $G$ (green) and $g$ (brown). After a drought, survival probabilities differ by genotype: $GG$ = 90% survive, $Gg$ = 70% survive, $gg$ = 20% survive. Assuming survivors are the ones that reproduce, which allele's frequency is expected to increase in the next generation?
A combined diagram includes these labeled arrows: Carbon (matter) arrows: Atmosphere (CO $_2$ ) → Producers (photosynthesis) Producers → Consumers (feeding) Consumers → Atmosphere (respiration) Decomposers → Atmosphere (decomposition) Energy arrows: Sun → Producers → Consumers, with heat-loss arrows leaving producers and consumers. Which choice correctly matches one matter-cycling process and one energy-flow feature shown by the arrows?
In a grassland ecosystem, producers contain about 60,000 kcal of energy. Using the 10% rule, how much energy is available to the primary consumers?
An endangered bird has about 60 individuals left in the wild. The main threats are (1) loss of nesting habitat to agriculture and (2) predation by introduced rats on eggs. A plan proposes captive breeding to increase numbers, then releasing birds back into the same area without changing land use or controlling rats. How effective is this plan likely to be at preserving the species long term?
A student draws this energy-flow model for a plant: [Sun] --(light energy)--> [Chlorophyll in chloroplast] --(powers photosynthesis)--> [Glucose] --(stored chemical energy)--> (A) [Cellular respiration releases energy for cell work] OR (B) [Stored as starch] According to the model, at which step is light energy converted into chemical energy stored in glucose?
Which pair correctly matches the type of reproduction with its typical genetic outcome in offspring?
Two versions of a lizard color trait exist: light and dark. In Habitat 1 (light sand), light lizards survive to reproduce at 0.90 and dark lizards at 0.10. In Habitat 2 (dark rock), light lizards survive at 0.55 and dark lizards at 0.45. In which habitat will the color trait frequencies change more rapidly due to natural selection?
Use the simplified carbon cycle diagram described below. Atmosphere (CO $_2$ ) --photosynthesis--> Plants --feeding--> Animals Animals --respiration--> Atmosphere (CO $_2$ ) Plants/Animals --death & waste--> Decomposers (soil) --decomposition--> Atmosphere (CO $_2$ ) Which sequence correctly traces carbon atoms from the air into a carnivore (an animal that eats other animals), following only the arrows shown?
Cells can use carbon atoms from glucose (C6H12O6) as raw material to build several types of macromolecules. Which option correctly matches a monomer to the polymer (macromolecule) it builds?
Which statement best describes what a chromosome is made of?
Which of the following correctly identifies the four nitrogenous bases found in DNA?

Practice tests