Question

question 3
scientists hypothesize that oxygen began to accumulate in earths atmosphere after the appearance of living things with the ability to __.

form tissues
reproduce sexually
photosynthesize
breathe air

question 4
photosynthesis occurs in specialized organelles called __.

mitochondria
ribosomes
chloroplasts
nuclear memebrane

Explanation:

Analyze atmospheric oxygen accumulation

The accumulation of oxygen in Earth's early atmosphere (the Great Oxidation Event) was driven by the emergence of organisms capable of producing oxygen as a byproduct of metabolic processes. Photosynthesis, specifically oxygenic photosynthesis performed by early cyanobacteria, splits water molecules and releases molecular oxygen (\(\text{O}_2\)) into the environment. Therefore, the appearance of living things with the ability to photosynthesize led to the accumulation of oxygen.

Identify the organelle where photosynthesis occurs

Photosynthesis in eukaryotic cells takes place within highly specialized double-membrane organelles. These organelles contain chlorophyll pigments that capture light energy to synthesize organic compounds. These specialized organelles are chloroplasts. Mitochondria are responsible for cellular respiration, ribosomes carry out protein synthesis, and the nuclear membrane encloses the genetic material.

Answer:

Question 3

• O form tissues
• O reproduce sexually
• O photosynthesize (Correct answer)
• O breathe air

Question 4

• O mitochondria
• O ribosomes</mcq-correct>
• O chloroplasts (Correct answer)

<mcq-option>O nuclear memebrane