plant systems

Which plant response would best aid a plant in maximizing and retaining water acquired during a drought?

• Decreasing root growth, while increasing stem and leaf growth

• Increasing root, stem, and leaf growth

• Decreasing stem and leaf growth, while increasing root growth

• Increasing leaf and root growth, while decreasing stem growth

Answer explanation

During a drought, decreasing stem and leaf growth while increasing root growth allows a plant to conserve water and enhance its ability to absorb moisture from the soil, maximizing water retention.

Tags

NGSS.MS-LS1-5

NGSS.MS-LS2-1

Which plant adaptation would most effectively help a plant conserve water during a prolonged dry period?

• Increasing the number of leaves to maximize photosynthesis

• Developing deeper roots to access underground water

• Expanding stem growth to store more water

• Growing larger leaves to shade the soil

Answer explanation

Developing deeper roots allows a plant to access underground water sources, which is crucial for survival during dry periods. This adaptation is more effective than increasing leaves or stem growth for water conservation.

Roots of different plants can be connected by a network of underground fungal extensions called hyphae. These fungi contribute minerals to the plants, and the plants contribute carbohydrates to the fungi. Which statement about the transportation of these substances within the plant is true?

• The minerals are transported from the phloem to the xylem in the shoot system.

• The carbohydrates are transported from the shoot system to the fungi by the xylem.

• The minerals are transported from the xylem to the phloem in the roots.

• The carbohydrates are transported to the fungi through the phloem.

Answer explanation

The correct statement is that carbohydrates are transported to the fungi through the phloem. Phloem is responsible for transporting organic nutrients, including carbohydrates, from the leaves to other parts of the plant.

Tags

NGSS.MS-LS2-3

Which statement supports the answer to the previous question?

• The xylem is part of the plant’s vascular tissues.

• The phloem transfers glucose throughout the plant.

• The xylem can move substances up from the roots.

• The phloem is connected to the roots by the xylem.

Answer explanation

The phloem transfers glucose throughout the plant, which is essential for energy and growth. This statement directly supports the answer by highlighting the role of phloem in nutrient distribution.

Tags

NGSS.MS-LS2-3

What is the primary function of the xylem in plants?

• To transport water and minerals from the roots to the rest of the plant.

• To transfer glucose throughout the plant.

• To store nutrients in the roots.

• To facilitate photosynthesis in the leaves.

Answer explanation

The primary function of the xylem is to transport water and minerals from the roots to the rest of the plant, making it essential for plant hydration and nutrient distribution.

What is the primary function of the phloem in plants?

• To transport water and minerals from the roots to the rest of the plant.

• To transfer glucose throughout the plant.

• To store nutrients in the roots.

• To facilitate photosynthesis in the leaves.

Answer explanation

The primary function of the phloem is to transfer glucose, produced during photosynthesis, throughout the plant. This process is essential for providing energy to various plant parts.

Tags

NGSS.MS-LS2-3

Positive thigmotropism is a response in plants in which they move and grow toward an object the plant comes into physical contact with, usually curling around the object. This response of the shoot system benefits the plant by allowing the plant to —

• produce more pollen for pollinators

• take in more carbon dioxide to convert into glucose

• absorb more water to transport to the leaves

• reach more sunlight for photosynthesis

Answer explanation

Positive thigmotropism allows plants to grow towards objects, helping them reach more sunlight. This is crucial for photosynthesis, enabling the plant to produce energy and thrive.

Tags

NGSS.MS-LS2-4

Students studying the interaction among the reproductive parts of flowering plants make the graphic organizer shown.

• A. (1) filaments, (2) petals, (3) stigma

• B. (1) petals, (2) ovule, (3) stigma

• C. (1) filaments, (2) petals, (3) ovule

• D. (1) petals, (2) stigma, (3) ovule

Answer explanation

The correct choice is D. Petals attract pollinators, the stigma receives pollen, and the ovule is where fertilization occurs, making this option accurately represent the reproductive parts of flowering plants.

Water, sugar, and other important nutrients need to be transported from one part of a plant to another. Which statement correctly describes the interaction of the root and shoot systems during nutrient transport?

• A. The leaves take in water and sugar, which are then transported to the rest of the plant through vascular tissues.

• B. The roots take in water and sugar, which are then transported to the rest of the plant through vascular tissues.

• C. The leaves take in water and the roots produce sugar that are transported to the rest of the plant through vascular tissues.

• D. The roots take in water and the leaves produce sugar that are transported to the rest of the plant through vascular tissues.

Answer explanation

The correct choice is D. Roots absorb water from the soil, while leaves produce sugar through photosynthesis. Both are transported through vascular tissues, ensuring the plant receives essential nutrients.

Tags

NGSS.MS-LS2-3

A flower that has both male and female reproductive structures is shown.

• An anther is transferred from a filament to another filament within the same flower.

• An ovule is transferred from the ovary to a petal on a different flower.

• A pollen grain is transferred from an anther to the stigma of the same flower.

• An ovary is transferred from a flower on one plant to a flower on a different plant.

Answer explanation

The correct choice describes pollination, where a pollen grain from the anther of a flower lands on its stigma, allowing fertilization. This process occurs within the same flower, making it the right answer.

Tags

NGSS.MS-LS1-4