Organisation- B2- Paper 1 Flashcards
Define a cell and give examples.
The basic building blocks of all living organisms.
E.g. sperm cells, root hair cells, nerve cells, muscle cells.
Define tissues and give examples.
A group of cells with similar structures and function working together
E.g. glandular tissue contains secretory cells that can produce and release substances such as enzymes and hormones, Epithelial tissue covers the outside of your body as well as your internal organs.
Define an organ and give examples.
A collection of tissues. Each organ contains several tissues, all working together to perform a specific function.
E.g. the stomach, is involved in the digestion of food. It contains muscular tissue, glandular tissue and epithelial tissue. The pancreas secretes hormones to control blood sugar as well as some enzymes that digest food.
Define organ systems and give examples.
Groups of organs that all work together to perform specific functions.
E.g. the digestive system, respiratory system and nervous system.
Define organisms and give examples.
A group of organ systems.
E.g. humans, dogs, cats
What are the main organs of a plant?
Stems, roots, and leaves
These organs work together to form organ systems that perform essential tasks for plant survival.
What is the role of plant tissues?
To make up organs and perform various functions
Examples of plant tissues include epidermal, mesophyll, xylem, phloem, and meristem tissues.
What type of tissue covers the whole plant?
Epidermal tissue
This tissue serves as a protective layer for the plant.
Where does most photosynthesis occur in a leaf?
Palisade mesophyll tissue
This tissue contains a high concentration of chloroplasts.
What is the function of spongy mesophyll tissue?
Contains big air spaces for gas diffusion
This adaptation allows for efficient exchange of gases within the leaf.
What do xylem and phloem transport?
Water, mineral ions, and food
Xylem transports water and nutrients upward, while phloem distributes glucose produced by photosynthesis.
What is meristem tissue responsible for?
Growth and differentiation into various cell types
It is found at the growing tips of shoots and roots.
What is the primary function of the waxy cuticle on epidermal tissues?
To reduce water loss by evaporation
This adaptation helps plants conserve water.
Why is the upper epidermis of a leaf transparent?
To allow light to pass through to the palisade layer
This is essential for photosynthesis.
What structure in the leaf contains chloroplasts?
Palisade layer
Chloroplasts are the sites of photosynthesis.
What forms a network of vascular bundles in a leaf?
Xylem and phloem
This network supports the leaf structure and facilitates transport.
What are stomata?
Little holes in the lower epidermis for gas exchange
They allow CO2 to diffuse directly into the leaf.
What controls the opening and closing of stomata?
Guard cells
These cells respond to environmental conditions.
Fill in the blank: The air spaces in the _______ increase the rate of gas diffusion.
spongy mesophyll tissue
These spaces facilitate efficient gas exchange within the leaf.
