Unit 3 Sht_1HWrkSht 3_1 

The Marking Guide has been made available. Use this where you are having difficulty, to help you understand the question better. Simply copying the answers from the Marking Guide will not help you learn, using it to help you understand the questions/ answers will. 

You will need your Glow login to access the Marking Guide. 

1. The following statements relate to specific functions of different cells. Match the diagrams below with the appropriate Function. In your jotter draw up a table to match the letter with the correct number (write numbers and letters only), include a column so that in each case you can name the cell type. 

Function A: The end walls of these cells are perforated to allow cytoplasm to move from one cell to another carrying food. These perforated end walls are called sieve plates. 

Function B: Found mainly on the bottom surface of a leaf and are sausage shaped with a thick inner cell wall facing stoma pores. They control gas exchange and water loss by changing shape and opening or closing the pores. 

Function C: These cells have a long fibre (insulated extension of cytoplasm). This is able to transmit nerve impulses long distances. 

Function D These cells  defend against illness. They have the ability to change shape and engulf micro-organisms in a process called phagocytosis. They contain lysosomes which contain powerful digestive enzymes to digest microbes. 

Function E: This cell is biconcave in shape, providing a large surface area for the uptake of oxygen. In addition there is no nucleus. This allows it to be filled with haemoglobin to pick up oxygen. 

Function F: They are long hollow tubes allowing water to easily move up through the plant.They are strengthened by rings or spirals of lignin. This helps to support the plant. 

Cell 1 

 

Cell 2 

 

Cell 3 

 

Cell 4 

 

Cell 5 

 

Cell 6 

2. Read the following passage and answer the questions which follow

 

Cells can be grouped together. A group of cells of the same type is called a tissue, therefore a group of muscle cells is called muscle tissue and a group of nerve cells is called nerve tissue. 

An organ is a part of the body with a particular job to do. For example the heart pumps blood and the stomach helps digest food. Each organ is made from a few very different tissues i.e the stomach contains both muscle and nerve tissue. 

More than one organ is needed to digest food, the stomach does some of the work but the mouth containing teeth and salivary glands and the intestines are other organs which help. The stomach and intestines form the digestive system, the heart and blood vessels form the circulatory system and they work together to circulate blood around the body. 

a) What term is given to a living organisms that consists of more than one cell? 

b) Most of these cells are specialised. What does this mean? 

c) What is a tissue? 

d) What structure is composed of several tissues working together? 

e) Name 2 types of tissue found in the stomach. 

f) Name the body system comprised of mouth, stomach and intestines? 

g) Name the main organs involved in the circulatory system. 

3. In your jotter, copy and complete the table below to show the name and function of many of the specialised cells within a leaf.

The video here will help your understanding of the leaf’s structure.(http://www.bbc.co.uk/learningzone/clips/adaptations-of-the-leaf-for-photosynthesis/10655.html)