Q1:Tissue: “A group of cells working together with a common function, structure and origin.”
Izen, M. (2015). Biology for A Level year one and AS. Illuminate publishing, Gloucestershire.
Q2a:Simple squamous epithelium is tissue formed by a single layer of simple squamous cells.
Q2b:Simple epithelial tissue can be found lining the chambers of the heart.
https://histology.leeds.ac.uk/tissue_types/epithelia/epi_simple.php accessed 28/09/2018
Q3:Organs can be complex hollow structures, tissues take an even shape. Tissue is a group of similar specialized cells grouped together to perform one relatively simple function. An organ is a group of tissues grouped together to carry out a more complex function. For example, the eye carries out the function of sight and contains nervous, connective, muscle and epithelial tissue each of which performs a specific function.
Izen, M. (2015). Biology for A Level year one and AS. Illuminate publishing, Gloucestershire.
Q4a:The Lungs contain both smooth muscle tissue, to contract allowing control of airflow, and simple squamous epithelial tissue, which lines the air sacs allowing passive diffusion of gases into and out of the blood stream.
Q4b:The Lungs are part of the respiratory system.
Q4c:The respiratory system is a system of organs and muscles which work together to allow us to inhale and exhale. The respiratory system allows oxygen from the air we breathe to be diffused into the blood, and carbon dioxide to be diffused from the blood into the alveola of the lungs to be exhaled.
Q4d:The trachea and the diaphragm are also part of the respiratory system.
Q5a:Osteocytes form bone tissue.
Q5b:
Q5c:the vertebral column is formed by bone tissue.
Q5d:1: Bone provides support by making up the framework for skeletal muscles enabling mobility of the whole body.
2: The compressive strength of bone tissue provides protection for internal organs, for example, the brain is protected by the cranial bones and the spinal cord is protected by the vertebrae.
3: Bone marrow tissue produces red blood cells, platelets and white blood cells.
4: Bone also provides storage for minerals such as calcium and phosphorous, when required these can be released back into the body to manage the balance of minerals.
Q6a:Ciliated columnar epithelial cells are polar. The basal side of the cells are attached to a basal membrane while the apical side faces towards an internal body cavity. Cilia are found on the apical side which moves secretions in a wave like motion. For example, ciliated epithelium which lines the respiratory tract secretes and removes mucus which may have trapped dust and bacteria.
In contrast, simple squamous epithelial cells are flatter in shape and packed tightly into a single layer with a smooth surface. These epithelia are common in parts of the body where absorption or transport of materials is essential to the function of the tissue. For example, in the lining of the lungs, the large surface area of the cells making up the simple squamous epithelium allows for absorption of oxygen down the concentration gradient into the blood.
Q7a:Cuboidal epithelium tissue can be found on the lining of the bronchioles in the lungs.
Q7b:Cuboidal epithelial tissue is specialized for secretion and absorption, for example cuboidal epithelial tissue covers the lens of the eye controlling nutrients and water passing in and out of the lens and the surrounding fluid.
Q8a:Tissue one is yellow elastic fibrocartilage.
Tissue two is white adipose tissue.
Q8b:White adipose tissue is loose fibrous connective tissue made up of densely packed adipocytes. They can be found in the subcutaneous layer under the skin and around some organs such as the kidneys and heart. They provide support and protection as well as acting as storage for energy in the form of fat.
Yellow elastic fibrocartilage is made up of a matrix of fibres which provide flexibility to organs such as the nose and ears. This elasticity is vital if the function of the organ involves movement, for example, the lungs.
Q9a:Skeletal muscle tissue can be found attached to bones via tendons for example, bicep muscles are attached to the radius in the human arm.
Q9b:Smooth muscle which can be found in blood vessels.
Q9c:Cardiac muscle is found in the heart.
Q9d:Diagram a is skeletal muscle tissue. It has bands of long, multinucleate cells with distinctive striations. Skeletal muscle tissue is attached to bones via tendons and contracts generating locomotion in mammals. They are also called voluntary muscles as contractions are under the control of the nervous system.
Diagram b is smooth muscle tissue. In contrast to skeletal muscle tissue, these smooth muscles are involuntary as we cannot consciously control their contractions. Cells are shorter, spindle shapes which taper at both ends and they have no striations. Cell junctions hold the smooth cells together and they can be found lining the walls of internal organs such as the stomach.
(Bradfield, P. et al. 2002)
Q10a: 1: Dendrites
2: Soma
3: Nucleus
4: Myelin Sheath
5: Axon Terminal
Q10b:The main function of nerve tissue is to perceive stimuli and generate nerve impulses. Nerve tissue of the peripheral nervous system collects signals from organs,
Q10c:The Axon Terminal transmits impulses to be received by the dendrite of a target neuron.
Q10d:Glial tissue provides nutrition and structure to neurons.
Q10e:The Brain and the Spinal Chord form the Central Nervous System.
