1.7
mitochondria – provide the energy for muscle contraction heart muscle cells protein filaments – slide over each other to produce muscle contraction
skeletal muscle
smooth muscle cells Type of muscle cell
Figure 1.26 There are three types of muscle cell. Muscle cells contain protein filaments which move to make the muscle contract. Muscle cells link with each other so a muscle contracts as a whole. 1
How are the following cells adapted to their functions:
KEY INFORMATION You can work out how the structure of a cell is related to its function, even if you are not familiar with the type of cell in the question. Look at the size, shape and surface area of the cell, and what it contains, for example mitochondria, ribosomes or a food store.
• a sperm cell • a muscle cell • a nerve cell? 2
Cells of the pancreas produce the hormone insulin. Insulin is a protein. Suggest how pancreatic cells are adapted for their function.
cell – heart muscle cell
Cells, tissues and organs Some cells work in isolation, like sperm cells. Others are grouped as tissues and work together. A tissue is a group of cells with a particular function. Many tissues have a number of similar types of cell to enable the tissue to function.
tissue – heart muscle
Tissues are grouped into organs. Organs carry out a specific function. Different organs are arranged into organ systems, for example the circulatory system, digestive system, respiratory system, and reproductive system. 3
Arrange the following in increasing order of size:
4
organ – the heart
system
cell
human body
organ
tissue
Name two other types of cell and one other type of tissue in the circulatory system.
organ system – the circulatory system
Figure 1.27 The organisation of the human circulatory system
Google search: 'differentiation, specialised cells, human body tissues'
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