7th Year / Science Review

In a school science project, Barbora and Filip are comparing plant and animal cells. Barbora points out that there is a specific component found in plant cells that is not present in animal cells. Which of the following components is Barbora referring to?

• Nucleus

• Chloroplast

• Cytoplasm

• Mitochondria

Answer explanation

Chloroplasts allow plants to photosynthesize; animals don't have them.

In a school, the principal is responsible for overseeing all activities and ensuring everything runs smoothly. What is the function of the nucleus in a cell?

• Produces energy

• Stores water

• Controls cell activities

• Helps with movement

Answer explanation

The nucleus stores DNA and controls cell functions.

During a science class, Ella and Alexej were discussing the differences between viruses and bacteria. Ella mentioned that viruses are different from bacteria because…

• They can reproduce on their own

• They are larger than bacteria

• They need a host cell to reproduce

• They are made of many cells

Answer explanation

Viruses reproduce only inside a host cell.

During a science class, Nela and Joshua were discussing different types of reproduction in plants and animals. Nela mentioned that a sunflower produces seeds, while Joshua pointed out that a bacterium divides into two. They were trying to figure out which of these examples is a case of asexual reproduction.

• A cat giving birth to kittens

• A sunflower producing seeds

• A bacterium dividing into two

• A frog laying eggs

Answer explanation

Bacteria reproduce by binary fission.

In a biology class, Zara and Ella are discussing the fundamental components of living organisms. Zara asks, 'What is the basic unit of heredity that determines traits in living beings?' Ella thinks for a moment and considers the options: 'Is it Protein, Gene, Cell, or Chromosome?' What do you think is the correct answer?

• Protein

• Gene

• Cell

• Chromosome

Answer explanation

Genes carry instructions for traits.

During a biology class, Denisa and Josef were discussing different groups of living organisms. Denisa mentioned that she loves cooking with mushrooms, while Josef was curious about what group mushrooms belong to. He asked, "Which group includes mushrooms?"

• Plants

• Fungi

• Animals

• Bacteria

Answer explanation

Mushrooms belong to fungi.

In a forest where Ella and Alexej are studying the ecosystem, they come across various organisms. They notice some unique organisms growing on the rocks and trees. What is the role of these lichens in the ecosystem?

• They are predators

• They are decomposers

• They produce oxygen at night

• They store energy for animals

Answer explanation

Lichens break down rocks and recycle nutrients.

During a sunny day in the school garden, Zara and Barbora are observing the plants. They notice that the leaves are shimmering in the sunlight. Zara asks, 'What gas do you think these plants are releasing as they grow?'

• Carbon dioxide

• Oxygen

• Nitrogen

• Hydrogen

Answer explanation

Photosynthesis produces oxygen.

During a science class, Emma and Mia are discussing how plants absorb water. Emma asks, 'Which part of the plant transports water from the roots?'

• Phloem

• Xylem

• Stomata

• Leaf blade

Answer explanation

Xylem carries water upward.

During a field trip to the desert, Emma noticed that cacti were thriving in the harsh environment. What adaptation allows these desert plants to survive?

• Large leaves

• Thick stems to store water

• Bright flowers

• Roots that float

Answer explanation

Succulent stems store water in dry environments.