Question

1. classify the following as a cell, tissue, organ, organ system or organism.

a group of nerve cells

stomach

all the leaves on a tree

heart, arteries, and veins

an amoeba (2 answers)

Explanation:

• A group of nerve cells: Nerve cells (neurons) grouped together form nerve tissue.
• Stomach: The stomach is an organ as it is made up of different tissues (epithelial, muscle, etc.) working together for a specific function (digestion).
• All the leaves on a tree: Leaves are organs of a plant. A group of leaves (all on a tree) can be considered an organ system (the photosynthetic and transpiration - related organ system in plants).
• Heart, arteries, and veins: These are parts of the circulatory system. The heart is an organ, arteries and veins are blood vessels (organs in a sense as they are made of tissues), and together they form the circulatory organ - system.
• An amoeba: An amoeba is a single - celled organism. Since it is a single cell that can carry out all life processes (like metabolism, reproduction), it is both a cell and an organism.

Answer:

• A group of nerve cells: Tissue
• Stomach: Organ
• All the leaves on a tree: Organ system
• Heart, arteries, and veins: Organ system
• An amoeba: Cell, Organism