Describe the function of the nucleolus
Produces ribosomes and RNA
Describe the function of the cell wall
Provides rigidity and protection to the
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Describe the function of the chloroplasts
Site of photosynthesis as they contain chlorophyll
Describe the function of the plasmodesmata
A channel through the cell wall the allows transport of materials from one cell to another
Describe the function of the amyoplasts
Stores starch and converts starch back into glucose when the plant needs energy
Describe the function of the vacuole
Stores water and chemicals for cell use. Also maintains turgor of cell
Describe the function of the tonoplasts
Membrane the surrounds the vacuole. Protects the vacuole, isolates it from harmful substances and controls water flow in and out of the vacuole
Why are gram positive bacteria more susceptible to antibiotics?
Permeable cell wall whereas gram negative bacteria has a semi-permeable cell wall
Describe the adaptations found in a palisade cell
Closely packed together
Chloroplasts
Large vacuole
Explain why the palisade cell has a large amount of chloroplasts
To absorb lots of light for photosynthesis
Explain why palisade cells are closely packed together
To form a continuous layer in the leaf
Explain why palisade cells have a large vacuole
To maintain turgor (pushes against the cell wall to maintain rigid shape)
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Describe the adaptations of a root hair cell
Root hair shape
Large vacuole
Thin cellulose walls
Explain why root hair cells have an elongated section known as the root hair
Increased surface area for maximum movement of water into the cell
Explain why root hair cells have a large vacuole
Contains cell sap with low water potential to encourage water into the cell
Explain why root hair cells have thin cellulose walls
Encourage movement of water and minerals into the cell. Short distance for osmosis and diffusion
Describe the adaptations of a sperm cell
Lots of mitochondria
Shaped head containing acrosome (with enzymes)
Haploid nucleus
Tail for movement
Explain why a sperm cell has an undulipodium (tail)
To allow the sperm to move to the egg
Explain why sperm cells contain large numbers of mitochondria
To produce the large amounts of energy needed for movement
Explain why sperm cells have a shaped head
To push through the protective layer of the egg cell
Explain why sperm cells contain acrosome in the head
To digest the zona pellucida to allow entry into the egg cell
Explain why sperm cells have a haploid nucleus
Contains half the genetic material.
Describe the adaptations of egg cells
Contains a haploid nucleus
Protective outer layer (zona pellucida)
Corona radiata
Explain why egg cells have a haploid nucleus
Contains half the genetic material
Explain why egg cells have a zona pellucida (protective layer)
Protects the cell and only allows one sperm cell to enter.
Explain why egg cells have a corona radiata (two or three layers attached to the zona pellucida)
Contains all of the proteins needed to develop the fertilised cell
Describe the adaptations of red blood cells
No nucleus (mammals only)
Biconcave shape
Haemoglobin
Flexible
Explain why red blood cells don't contain a nucleus
Allows for more oxygen to be carried in the cell
Explain why red blood cells have a biconcave shape
Increased surface area for gas exchange
Explain why red blood cells contain haemoglobin
To bind with the oxygen in order for it to be carried around the body
Explain why red blood cells are flexible
To fit through the tiny blood vessels such as capillaries
Describe the adaptations of white blood cells
Multi-lobed nucleus
Enzymes found within the lysosomes
Explain why white blood cells have a multi-lobed nucleus
To enable the cell to squeeze through tiny gaps when travelling to the site of infection
Explain why the lysosomes found within the cytoplasm of white blood cells contain enzymes
To digest engulfed pathogens
Name the 3 different types of epithelial tissue
Squamous epithelial tissue
Columnar epithelial tissue
Endothelium tissue
Describe squamous epithelial tissue
A lining tissue that is only one cell thick. Made from squamous cells that form a smooth, flat layer.
Where can squamous epithelial tissue be found?
As it is a lining tissue it can be found inside alveoli
How can squamous epithelial tissue be damaged by smoking?
Inflammation and scarring of tissue
Tissue gets thicker and produces more mucus
Diffusion pathway is increased
What does COPD stand for?
Chronic Obstructive Pulmonary Disorder
What symptoms can be displayed from COPD?
Breathlessness
Persistent coughing
Phlegm build up
What conditions are considered part of COPD?
Emphysema
Bronchitis
Asthma
Describe columnar epithelial tissue
Column shaped ciliated cells and goblet cells held in place by a membrane
What is meant by the term ciliated cell?
A cell covered in cilia. Cilia are fine, hair like projections that 'sweep' away pathogens from the lungs
How does smoking affect ciliated columnar tissue?
The cilia can break, lessening the 'sweeping action' overall. This leads to a build-up of mucus.
What is the role of the goblet cell?
To produce mucus
How do goblet cells and ciliated cells work together?
Goblet cells produce mucus that sticks to pathogens, whilst cilia 'sweep' away the mucus containing the pathogens
How does smoking affect the alveoli?
Reduces the elasticity so pockets of air form that cannot be expelled
Where is endothelial tissue found?
Lining the inside of blood vessels, lymphatic vessels and the heart
Describe the structure of endothelial tissue
A layer of flattened cells, one layer thick
What is atherosclerosis?
The process of white blood cells encouraging the deposition of fatty substances (cholesterol) below the endothelial lining
What factors can increase the likelihood of atherosclerosis?
Smoking
High blood pressure
What conditions can atherosclerosis cause?
Angina
TIA (mini strokes)
Heart attack
Aneurysm and haemorrhage
Name the three types of muscle tissue
Skeletal
Cardiac
Smooth
What type of control is exhibited in skeletal muscle?
Voluntary control
What type of control is exhibited in cardiac muscle?
Involuntary control
What type of control is exhibited in smooth muscle?
Involuntary control
Where can skeletal muscle be found?
Attached to bones
Where can cardiac muscle be found?
In the heart
Where can smooth muscle be found?
In the walls of hollow organs such as the stomach and bladder
Put the following in order of size from largest to smallest: fibre, muscle, filaments, myofibril, bundle of fibres
Muscle, bundle of fibres, fibre, myofibril, filaments
Muscle fibres are many cells joined together. What organelles do these cells share?
Nuclei and cytoplasm, inside which are many mitochondria and specialised ER [Show Less]