5th grade help lines

Which is the main light-absorbing pigment for photosynthesis?

carotene

chlorophyll

hemoglobin

anthocyanin

Photosynthesis occurs in the plant’s chloroplasts, where energy from sunlight is captured and used to start a reaction that produces several products. What is one way that photosynthesis benefits all living things?

Photosynthesis creates glucose in the plants, which is used as energy by animals that then eat the plants.

Photosynthesis increases the level of carbon dioxide in the air, which is necessary for animals to breathe.

Photosynthesis makes the soil more nutrient-rich because glucose is created, resulting in increased crops.

Photosynthesis creates water, which contributes to the water cycle and prevents drought.

Ivan is looking at a cross section of a stem taken from a vascular plant. He sees two different types of vascular tissue: the xylem, which is closer to the center of the stem, and the phloem, located around the xylem, closer to the outside of the stem. How do these two structures work together in a living plant?

Phloem carries water and food between the roots and other structures of the plants, while xylem provides support and structure to the stem.

Xylem carries water and minerals from the roots of the plants to the leaves and flowers, and phloem carries food made through photosynthesis to the other structures of the plants.

Both types of vascular tissue carry water, food made through photosynthesis, and nutrients from the soil from the roots to the leaves and back to the roots again.

Phloem carries water and minerals from the roots, while xylem carries the food made through photosynthesis to the leaves.

Fiona wants to use the scientific method to answer the question “Do oxygen levels in the air affect rates of photosynthesis?” She reads about photosynthesis in her biology book and is ready to carry out the next step. What should she do next?

perform an experiment

design a procedure

make observations

form a hypothesis

Which is the first step in the scientific method?

ask a question

conduct background research

construct a hypothesis

perform an experiment

All plants we see today had ancestors that lived in the water. One of the reasons plants began to live on land was

decreased exposure to fish that eat plants.

decreased competition from other plants.

increased exposure to oxygen.

decreased exposure to salt in the ocean water.

Which is required for the light-independent reactions in photosynthesis to occur?

water

sunlight

oxygen

carbon dioxide

What is one role of ATP in the light-independent reaction of photosynthesis?

ATP supplies the energy to produce glucose and other carbohydrates.

ATP is produced when water molecules are split and chlorophyll electrons are excited.

ATP supplies the energy to split water molecules.

ATP produces CO2 and O2 molecules.

One differentiating characteristic between vascular and nonvascular plants is the lack of active transport structures in the nonvascular plants. How does the lack of xylem or phloem contribute to the smaller size of the nonvascular plants?

Nonvascular plants are smaller because xylem and phloem help a plant stand up taller.

Nonvascular plants have other transport structures that are microscopic and therefore take up less room.

Nonvascular plants rely upon concentration gradients to move food and water, which only works over small distances.

Nonvascular plants are smaller because they don’t photosynthesize as much as vascular plants and don’t get enough food.

Vascular plants have two different types of specialized tissues that transport food, water, and nutrients to the various plant structures. What would be the effect on a vascular plant if the phloem became damaged?

The plant would be fine because the phloem is more of a support structure than a vascular tissue.

The plant would be fine since the xylem would take over for the injured phloem.

The plant would most likely die because it couldn’t get water to the leaves.

The plant would most likely die because it could not get glucose to the growing parts of the plants.

Which statement best describes what a thylakoid does during photosynthesis?

surrounds the grana and keeps them moist

enables the light-dependent reactions to occur

combines carbon dioxide and water to make sugar

helps the light-independent reactions to occur

In the chemical equation for photosynthesis, carbon dioxide and water are converted to glucose and oxygen.

6CO2 + 6H2O ® C6H12O6 + 6O2

Which component could be added to complete this chemical equation?

light energy

ATP and NADPH

chemical energy

rubisco

Which is the best description of photophosphorylation?

the absorption of light energy by chlorophyll

the conversion of light energy to chemical energy

the removal of a phosphate group from a molecule

the conversion of ADP to ATP using light energy

Which process is catalyzed by rubisco during the light-independent reactions of photosynthesis?

glycolysis

carbon fixation

reduction

regeneration