science Flashcards
(17 cards)
What is the function of the cuticle?
Prevent water loss within the leaf
The cuticle is a thin waxy covering on the outer surface of the leaf.
What layer of cells is directly underneath the cuticle?
Upper epidermis
The upper epidermis is composed of cells with no nucleus to allow sunlight to pass through for photosynthesis.
What is the mesophyll?
A layer of cells within the leaf that contains chloroplasts for photosynthesis
The mesophyll can be divided into the palisade layer and the spongy layer.
What are the characteristics of palisade mesophyll?
Column-like cells with many chloroplasts and elongated shape
These adaptations maximize photosynthesis.
What is the spongy mesophyll?
A layer of loosely packed cells with air spaces for gas exchange
The air spaces between spongy cells allow gases to diffuse in and out.
What is located directly above the cuticle?
Lower epidermis
The lower epidermis contains many pores.
What are stomata?
Tiny holes within the lower epidermis that allow gas exchange
Stomata are surrounded by specialized cells called guard cells.
What is the function of guard cells?
Surround stomata and control their opening and closing
This regulation allows gases to enter and exit the leaf.
What does xylem transport?
Water and minerals from the roots to the leaf
Xylem makes up the top part of the vascular bundle.
What does phloem transport?
Sugars around the plant, both up and down
Phloem makes up the bottom part of the vascular bundle.
What is the primary function of chloroplasts?
Absorb sunlight for photosynthesis
Chloroplasts are essential for the process of photosynthesis in plant cells.
Why do plant cells in the root not have chloroplasts?
Sunlight cannot reach the roots, so they do not photosynthesize
Therefore, chloroplasts are unnecessary in root cells.
What are the organs of plants?
- Leaves
- Stem
- Root
These organs work together to support the plant’s life processes.
How are leaves adapted for photosynthesis?
- Thin waxy cuticle
- Upper epidermis with no nucleus
- Mesophyll with chloroplasts
- Palisade mesophyll for maximizing light absorption
- Spongy mesophyll for gas exchange
- Lower epidermis with pores
- Stomata for gas exchange
- Guard cells for regulation
These adaptations enhance the efficiency of photosynthesis.
Fill in the blank: The _______ allows gases to enter and exit the leaf.
stomata
Stomata are essential for gas exchange in plants.
True or False: The palisade mesophyll contains more chloroplasts than the spongy mesophyll.
True
Palisade cells are specifically adapted for photosynthesis with a higher concentration of chloroplasts.
