GACE Biology 2

Question 1

Which organelle is primarily responsible for ATP synthesis through oxidative phosphorylation in eukaryotic cells?

Accepted Answer

Mitochondria

Answer

Mitochondria carry out oxidative phosphorylation via the electron transport chain and ATP synthase to produce the majority of cellular ATP.

Question 2

A student observes that a population of beetles in a field has shifted from mostly green to mostly brown over 20 generations. Which mechanism best explains this change if brown beetles survive predation better?

Accepted Answer

Natural selection

Answer

Natural selection favors traits that increase survival and reproduction, so brown coloration providing better camouflage increases in frequency over generations.

Question 3

Which bond type links nucleotides together to form the backbone of a DNA strand?

Accepted Answer

Phosphodiester bonds

Answer

Phosphodiester bonds connect the 3' hydroxyl of one nucleotide to the 5' phosphate of the next, forming the sugar-phosphate backbone.

Question 4

During meiosis I, homologous chromosomes exchange genetic material through a process called:

Accepted Answer

Crossing over

Answer

Crossing over (recombination) occurs at chiasmata during prophase I, exchanging segments between non-sister chromatids of homologous chromosomes.

Question 5

An ecosystem experiences the removal of all top predators. According to trophic cascade theory, what is the most likely outcome?

Accepted Answer

Herbivore populations increase and primary producer biomass decreases

Answer

Without top predators to control herbivore populations, herbivores increase and overconsume primary producers, reducing their biomass.

GACE - Georgia Assessments for the Certification of Educators Practice Test

GACE - Georgia Assessments for the Certification of Educators Practice Test

GACE Biology 2