Heterogeneous tissues are -

Options

A. vascular and cork cambia
B. Xylem and phloem elements
C. Dermal layer and ground tissue
D. Parenchyma and sclerenchyma

Answer

### Step-by-Step Solution:

1. **Definition of Heterogeneous Tissues**:
Heterogeneous tissues are composed of different types of cells that perform various functions. Unlike homogeneous tissues, which consist of similar cells, heterogeneous tissues exhibit a diversity of cell types.

**Hint**: Remember that "hetero-" means different, which indicates the variety in cell types.

2. **Examples of Heterogeneous Tissues**:
Common examples of heterogeneous tissues include connective tissues, nervous tissues, and some types of epithelial tissues. Each of these tissues contains a mix of different cell types that contribute to their overall function.

**Hint**: Think about the various functions of tissues in the body and how different cells contribute to these functions.

3. **Functions of Heterogeneous Tissues**:
The diverse cell types within heterogeneous tissues allow for specialized functions. For instance, in connective tissue, you may find cells that provide support (like fibroblasts), cells that store fat (adipocytes), and cells involved in immune responses (macrophages).

**Hint**: Consider how the specialization of different cells can enhance the overall functionality of a tissue.

4. **Structural Characteristics**:
Heterogeneous tissues often have a complex structure. The arrangement of different cell types can vary, and they may be embedded in a matrix that provides additional support and facilitates communication between cells.

**Hint**: Visualize how different cells might be arranged in a tissue and how they interact with each other.

5. **Importance in Organ Systems**:
Heterogeneous tissues play crucial roles in forming organs and systems within the body. Their complexity allows for the integration of various functions necessary for the survival of the organism.

**Hint**: Think about how organs are made up of different tissues working together to perform specific functions.

### Summary:
Heterogeneous tissues are characterized by their composition of diverse cell types that work together to perform specialized functions. They are essential for the proper functioning of organs and systems in living organisms. Examples include connective and nervous tissues, which showcase the variety of cell types and their roles.