Photosynthesis - Anatomy of Leaves and function

Question 1

What are the major types of cell in a leaf?

Answer 1

Epidermal cells, Parenchyma cells, Mesophyll cells and Guard cells

Question 2

What are the major photosynthetic parts of many plants?

Answer 2

Leaves

Question 3

Where are leaves typically borne on a plant?

Answer 3

The nodes of a stem

Question 4

What happens to leaves at the end of their lifetime?

Answer 4

Leaves are replaced at growing seasons.

Question 5

What are the three major patterns of leaf arrangement on plant stems?

Answer 5

Alternate, opposite, or whorled

Question 6

What is the connection between the leaf blade and the plant stem called?

Answer 6

Petiole

Question 6

What are the epidermal hairs on the upper and lower surfaces of the leaf and these can also help retard water loss.

Answer 6

Trichomes

Question 7

In what ways can leaves be modified?

Answer 7

Protection (e.g., spines) or climbing (e.g., tendrils in vines).

Question 8

How is the structure of leaves generally described?

Answer 8

Leaves are usually flat and have one surface facing towards the stem axis and the other surface facing the opposite direction.

Question 9

What role does the xylem play in leaf function?

Answer 9

Xylem brings water and minerals to the leaves.

Question 10

What is the function of phloem in leaves?

Answer 10

Phloem transports the products of photosynthesis to other plant parts such as storage organs.

Question 11

Why is it beneficial for plants to have a flat leaf structure?

Answer 11

A flat leaf structure maximizes surface area for capturing sunlight, which is essential for photosynthesis.

Question 12

How do leaves contribute to the overall function of the plant?

Answer 12

Leaves contribute to the overall function of the plant by performing photosynthesis and facilitating the transport of nutrients and water.

Question 13

What are the two types of tissues that make up veins in leaves?

Answer 13

Xylem and Phloem

Question 14

Why is the arrangement of leaves important for plants?

Answer 14

To maximize the capability of the plant to capture sunlight.

Question 15

What are trichomes, and where can they be found on leaves?

Answer 15

They are epidermal hairs and it can be present on the upper and lower surfaces of the leaf and help retard water loss.

Question 16

How do stomata facilitate gaseous exchange?

Answer 16

Stomata are openings that allow for the exchange of gases (e.g., carbon dioxide and oxygen) between the intercellular spaces and the external environment.

Question 17

What regulates the opening and closing of the stoma?

Answer 17

Changes in the osmotic concentration of the vacuoles within the guard cells regulate the opening and closing of the stoma.

Question 18

What is the role of the cuticle in leaf anatomy?

Answer 18

The cuticle limits water loss from the leaf by providing a waterproof barrier.

Question 18

What is the primary function of the mesophyll layer in leaves?

Answer 18

The mesophyll layer is specialized for carrying out photosynthesis.

Question 19

What happens to water vapor in regards to stomata?

Answer 19

There is a one-way net diffusion of water vapor from the intercellular spaces to the atmosphere through the stomata.

Question 20

What is the primary function of epidermal cells in leaves?

Answer 20

Provide a protective outer layer and help limit water loss from the leaf.

Question 21

What cellular organelles are abundant in mesophyll cells?

Answer 21

Chloroplasts.

Question 22

Describe the arrangement of palisade mesophyll cells.

Answer 22

They’re stacked like columns with their long axes oriented at right angles to the epidermis.

Question 22

What different types of mesophyll are mentioned in the text?

Answer 22

Palisade Mesophyll and Spongy Mesophyll.

Question 22

How do palisade and spongy mesophyll differ in structure?

Answer 22

Palisade mesophyll cells are closely packed and has a column like shape, while spongy mesophyll cells are more loosely arranged with larger intercellular air spaces and shapes irregular.

Question 23

Why is the arrangement of palisade mesophyll cells beneficial for photosynthesis?

Answer 23

To reduces the number of light-absorbing cell walls between sunlight and chloroplasts, allowing for more efficient light absorption.

Question 23

Where are stomata typically located in dicotyledonous leaves?

Answer 23

Lower epidermis

Question 23

What is the function of guard cells in relation to stomata?

Answer 23

To regulate the opening and closing of the stomata based on environmental conditions.

Question 23

What gases are exchanged during photosynthesis?

Answer 23

During photosynthesis, carbon dioxide is taken in, and oxygen and water vapor are given out.

Question 24

What is the primary benefit of having choroplast-rich mesophyll cells?

Answer 24

Chloroplast-rich mesophyll cells optimize the capture of light energy for photosynthesis.

Question 25

What happens to the osmotic concentration of guard cells when they are stimulated to open the stomata?

Answer 25

The osmotic concentration of guard cells increases, causing water to flow in and the guard cells to swell, which opens the stomata.

Question 25

Why might plants have epidermal hairs on their leaves?

Answer 25

To reduce water loss and can provide some protection against herbivores.

Question 25

How do the number of chloroplasts in spongy mesophyll cells compare to those in palisade mesophyll cells?

Answer 25

Spongy mesophyll cells have fewer chloroplasts than palisade mesophyll cells.

Question 26

How do intercellular spaces contribute to the process of photosynthesis?

Answer 26

The large volume of intercellular spaces facilitates the gaseous exchange needed for photosynthesis.

Question 26

What wavelengths of light do spongy mesophyll cells intercept?

Answer 26

Wavelengths of light that were not captured by the upper palisade mesophyll cells.

Question 26

What is the significance of water vapor diffusion for plants?

Answer 26

For maintaining transpiration, which helps with nutrient transport and temperature regulation in plants.

Question 26

What is unique about the photosynthesis that occurs in spongy mesophyll?

Answer 26

It uses light of a higher wavelength than that used by palisade mesophyll.

Question 26

What structures are found in the mesophyll layer of leaves?

Answer 26

They are continuous with the vascular system of the stem and the entire plant.

Question 27

What surrounds the vascular tissues of the leaf veins?

Answer 27

Parenchyma cells that have a small number of chloroplasts.

Question 27

What structure do parenchyma cells form around the vascular tissues?

Answer 27

The bundle sheath.

Question 27

What types of substances must pass through the bundle sheath?

Answer 27

Water, mineral ions, photosynthesis products, and metabolic products.

Question 27

How do chloroplasts move within the cell?

Answer 27

Using the cytoskeleton inside the cell.

Question 27

Why is it important that bundle sheaths extend to the ends of the smallest veins?

Answer 27

To ensure that no parts of the veins are exposed to air in the intercellular spaces.

Question 28

What feature of plant cells takes up most of the interior of the cell?

Answer 28

Vacuole

Question 28

What adaptations do leaves have to maximize the capture of sunlight for photosynthesis?

Answer 28

Chloroplasts can move and change orientation to catch the most light.

Question 28

What must all substances pass through when entering or leaving the vascular bundle?

Answer 28

The bundle sheath.

Question 29

What binds the chloroplasts to the specific location within the cells?

Answer 29

The organization of the cytoplasm and the presence of a large vacuole.

Question 29

How does the structure of the spongy mesophyll facilitate photosynthesis?

Answer 29

By having air spaces for gas exchange and intercepting light.

Question 29

Why is the position of cytoplasm important in relation to chloroplasts?

Answer 29

It restricts chloroplasts to the area of the cell where the most light can reach them.

Question 29

What is the main purpose of intercellular air spaces in spongy mesophyll?

Answer 29

To facilitate efficient gaseous exchange.

Question 30

What is the shape of spongy mesophyll cells?

Answer 30

Irregular in shape.

Question 30

Where are spongy mesophyll cells located in the leaf?

Answer 30

On the lower side of leaves.

Question 30

Why do spongy mesophyll cells have irregular shapes?

Answer 30

To create large intercellular air spaces for efficient gaseous exchange.