BTEC Applied Science Unit 1 Biology Exam 118 Questions with Answers
Describe the function of the nucleolus - CORRECT ANSWER Produces ribosomes and
... [Show More] RNA
Describe the function of the cell wall - CORRECT ANSWER Provides rigidity and protection to the cell
Describe the function of the chloroplasts - CORRECT ANSWER Site of photosynthesis as they contain chlorophyll
Describe the function of the plasmodesmata - CORRECT ANSWER A channel through the cell wall the allows transport of materials from one cell to another
Describe the function of the amyoplasts - CORRECT ANSWER Stores starch and converts starch back into glucose when the plant needs energy
Describe the function of the vacuole - CORRECT ANSWER Stores water and chemicals for cell use. Also maintains turgor of cell
Describe the function of the tonoplasts - CORRECT ANSWER 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? - CORRECT ANSWER Permeable cell wall whereas gram negative bacteria has a semi-permeable cell wall
Describe the adaptations found in a palisade cell - CORRECT ANSWER Closely packed together
Chloroplasts
Large vacuole
Explain why the palisade cell has a large amount of chloroplasts - CORRECT ANSWER To absorb lots of light for photosynthesis
Explain why palisade cells are closely packed together - CORRECT ANSWER To form a continuous layer in the leaf
Explain why palisade cells have a large vacuole - CORRECT ANSWER To maintain turgor (pushes against the cell wall to maintain rigid shape)
Describe the adaptations of a root hair cell - CORRECT ANSWER Root hair shape
Large vacuole
Thin cellulose walls
Explain why root hair cells have an elongated section known as the root hair - CORRECT ANSWER Increased surface area for maximum movement of water into the cell
Explain why root hair cells have a large vacuole - CORRECT ANSWER Contains cell sap with low water potential to encourage water into the cell
Explain why root hair cells have thin cellulose walls - CORRECT ANSWER Encourage movement of water and minerals into the cell. Short distance for osmosis and diffusion
Describe the adaptations of a sperm cell - CORRECT ANSWER Lots of mitochondria
Shaped head containing acrosome (with enzymes)
Haploid nucleus
Tail for movement
Explain why a sperm cell has an undulipodium (tail) - CORRECT ANSWER To allow the sperm to move to the egg
Explain why sperm cells contain large numbers of mitochondria - CORRECT ANSWER To produce the large amounts of energy needed for movement
Explain why sperm cells have a shaped head - CORRECT ANSWER To push through the protective layer of the egg cell
Explain why sperm cells contain acrosome in the head - CORRECT ANSWER To digest the zona pellucida to allow entry into the egg cell
Explain why sperm cells have a haploid nucleus - CORRECT ANSWER Contains half the genetic material.
Describe the adaptations of egg cells - CORRECT ANSWER Contains a haploid nucleus
Protective outer layer (zona pellucida)
Corona radiata
Explain why egg cells have a haploid nucleus - CORRECT ANSWER Contains half the genetic material
Explain why egg cells have a zona pellucida (protective layer) - CORRECT ANSWER 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) - CORRECT ANSWER Contains all of the proteins needed to develop the fertilised cell
Describe the adaptations of red blood cells - CORRECT ANSWER No nucleus (mammals only)
Biconcave shape
Haemoglobin
Flexible
Explain why red blood cells don't contain a nucleus - CORRECT ANSWER Allows for more oxygen to be carried in the cell
Explain why red blood cells have a biconcave shape - CORRECT ANSWER Increased surface area for gas exchange
Explain why red blood cells contain haemoglobin - CORRECT ANSWER To bind with the oxygen in order for it to be carried around the body
Explain why red blood cells are flexible - CORRECT ANSWER To fit through the tiny blood vessels such as capillaries
Describe the adaptations of white blood cells - CORRECT ANSWER Multi-lobed nucleus
Enzymes found within the lysosomes
Explain why white blood cells have a multi-lobed nucleus - CORRECT ANSWER 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 - CORRECT ANSWER To digest engulfed pathogens
Name the 3 different types of epithelial tissue - CORRECT ANSWER Squamous epithelial tissue
Columnar epithelial tissue
Endothelium tissue
Describe squamous epithelial tissue - CORRECT ANSWER 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? - CORRECT ANSWER As it is a lining tissue it can be found inside alveoli
How can squamous epithelial tissue be damaged by smoking? - CORRECT ANSWER Inflammation and scarring of tissue
Tissue gets thicker and produces more mucus
Diffusion pathway is increased
What does COPD stand for? - CORRECT ANSWER Chronic Obstructive Pulmonary Disorder
What symptoms can be displayed from COPD? - CORRECT ANSWER Breathlessness
Persistent coughing
Phlegm build up
What conditions are considered part of COPD? - CORRECT ANSWER Emphysema
Bronchitis
Asthma
Describe columnar epithelial tissue - CORRECT ANSWER Column shaped ciliated cells and goblet cells held in place by a membrane
What is meant by the term ciliated cell? - CORRECT ANSWER 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? - CORRECT ANSWER 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? - CORRECT ANSWER To produce mucus
How do goblet cells and ciliated cells work together? - CORRECT ANSWER Goblet cells produce mucus that sticks to pathogens, whilst cilia 'sweep' away the mucus containing the pathogens
How does smoking affect the alveoli? - CORRECT ANSWER Reduces the elasticity so pockets of air form that cannot be expelled
Where is endothelial tissue found? - CORRECT ANSWER Lining the inside of blood vessels, lymphatic vessels and the heart
Describe the structure of endothelial tissue - CORRECT ANSWER A layer of flattened cells, one layer thick
What is atherosclerosis? - CORRECT ANSWER 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? - CORRECT ANSWER Smoking
High blood pressure
What conditions can atherosclerosis cause? - CORRECT ANSWER Angina
TIA (mini strokes)
Heart attack
Aneurysm and haemorrhage
Name the three types of muscle tissue - CORRECT ANSWER Skeletal
Cardiac
Smooth
What type of control is exhibited in skeletal muscle? - CORRECT ANSWER Voluntary control
What type of control is exhibited in cardiac muscle? - CORRECT ANSWER Involuntary control
What type of control is exhibited in smooth muscle? - CORRECT ANSWER Involuntary control
Where can skeletal muscle be found? - CORRECT ANSWER Attached to bones
Where can cardiac muscle be found? - CORRECT ANSWER In the heart
Where can smooth muscle be found? - CORRECT ANSWER 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 - CORRECT ANSWER Muscle, bundle of fibres, fibre, myofibril, filaments
Muscle fibres are many cells joined together. What organelles do these cells share? - CORRECT ANSWER Nuclei and cytoplasm, inside which are many mitochondria and specialised ER
Why do muscle cells contain many mitochondria? - CORRECT ANSWER To provide large amounts of energy to the muscle for contractions
Give the term used to describe the stripy bands seen within skeletal muscle under a microscope - CORRECT ANSWER Striations
Myofibril is made up of dark and light bands. What are the names given to these dark and light bands? - CORRECT ANSWER Dark band = A-band
Light band = I-band
Which line is present in the middle of the A-band? - CORRECT ANSWER M line
Which line is present in the middle of the I-band? - CORRECT ANSWER Z line
What is the name given to the space between two Z-lines? - CORRECT ANSWER Sarcomere
Myofibril is made up of alternating thick and thin filaments. What are the names of these filaments? - CORRECT ANSWER Thick = myosin filament
Thin = actin filament
What happens to the sarcomere during muscle contraction? - CORRECT ANSWER It shortens
What are the two types of skeletal muscle? - CORRECT ANSWER Fast twitch and slow twitch
Which sports are slow twitch muscle fibres best for? - CORRECT ANSWER Long distance running and cycling
Fast twitch muscles can be further divided into two sub-categories, what are they? - CORRECT ANSWER Fast twitch oxidative muscles and fast twitch glycolytic muscles
Which sports are fast twitch oxidative muscle fibres best for? - CORRECT ANSWER Mid-range sports such as1500m
Which sports are fast twitch glycolytic muscle fibres best for? - CORRECT ANSWER Sprinting, short burst sports
What type of exercise are slow twitch muscles designed for? - CORRECT ANSWER Aerobic exercise
What type of exercise are fast twitch muscles designed for? - CORRECT ANSWER Anaerobic exercise
In which type of muscle fibre is the speed of contraction slowest? - CORRECT ANSWER Slow twitch
In which type of muscle fibre is the speed of contraction highest? - CORRECT ANSWER Fast glycolytic twitch
Describe the characteristics of slow twitch muscle fibres - CORRECT ANSWER Less sarcoplasmic reticulum (specialised ER)
More mitochondria
More myoglobin
A dense capillary network
Describe the characteristics of fast oxidative muscle fibres - CORRECT ANSWER Similar to slow twitch with many mitochondria, myoglobin and capillaries
Hydrolyse ATP faster to contract more quickly
Describe the characteristics of fast glycolytic twitch muscle fibres - CORRECT ANSWER Few mitochondria and capillaries
Less myoglobin
Large concentration of glycogen for anaerobic respiration
What structures make up the nervous system? - CORRECT ANSWER Brain, spinal cord, nerves
What is the scientific name for nerve cells? - CORRECT ANSWER Neurones
Name the organelles of the neurone - CORRECT ANSWER Dendrite, cytoplasm, nucleus, soma, axon, myelin sheath, axon terminal, Schwann cell, node of Ranvier
What parts of the nervous system make up the central nervous system? - CORRECT ANSWER Brain and spinal cord
Which parts of the nervous system make up the peripheral nervous system? - CORRECT ANSWER Neurones
Define the term 'synapse' - CORRECT ANSWER The small gap in between the axon terminal of one neurone and the dendrite of the next neurone
Define the term 'action potential - CORRECT ANSWER The impulse passed along the axon
Define the term 'resting potential - CORRECT ANSWER When the neurone is not transmitting an action potential. During this time the K+/Na+ pump is at work
What are the 5 sensory receptors? - CORRECT ANSWER Touch, taste, smell, hearing, sight
Describe the myelin sheath - CORRECT ANSWER A thick insulating layer around the axon
Describe the dendrites - CORRECT ANSWER Highly branched fibres that conduct impulses
Describe the axon - CORRECT ANSWER A long single fibre that carries nerve impulses
Describe the Schwann Cell - CORRECT ANSWER A cell wrapped around the axon, forming the myelin sheath
Describe the nodes of Ranvier - CORRECT ANSWER Gap in the myelin sheath where the axon is exposed
Describe the differences between myelinated and non-myelinated cells - CORRECT ANSWER Myelinated cells are longer and can transmit impulses faster down the axon
Why do myelinated neurones transmit action potentials quicker than non-myelinated - CORRECT ANSWER Insulated by myelin sheath
Impulse 'jumps' from node to node (where the sodium gates are located)
What is the potential difference across the axon membrane during resting potential? - CORRECT ANSWER -70mV
What is the potential difference across the axon membrane during an action potential? - CORRECT ANSWER +35mV
What charge does the inside of an neurone have when it is polarised? - CORRECT ANSWER Negative
What charge does the inside of a neurone have when it is depolarised? - CORRECT ANSWER Positive
During resting potential which ions are being moved into the cell and which ions are moved out of the cell? - CORRECT ANSWER Na+ removed from the cell, K+ added to the cell
How many sodium/potassium ions are removed/added in via the Na+/K+ pump? - CORRECT ANSWER 3 Na+ ions removed, 2 K+ ions added
When does the first voltage gate open? - CORRECT ANSWER When the axon is stimulated and this reaches above potential threshold
Which voltage gates are open during resting potential? - CORRECT ANSWER None
Which voltage gates are open during depolarisation? - CORRECT ANSWER Sodium voltage gates
Which voltage gates are open during repolarisation? - CORRECT ANSWER Potassium voltage gates
What occurs during depolarisation? - CORRECT ANSWER Na+ voltage gates open, Na+ floods in causing the potential difference to increase
What occurs during repolarisation? - CORRECT ANSWER K+ voltage gates open, K+ floods out of the cell causing potential different to decrease
What is meant by the term hyper-polarisation? - CORRECT ANSWER When the cell becomes too negative due to the loss of too many K+
What is meant by the term saltatory conduction? - CORRECT ANSWER When the impulse jumps between nodes increasing the speed at which the impulse travels down the axon
Which voltage gate opens in the synaptic bulb as the action potential reaches it? - CORRECT ANSWER Calcium voltage gate
What happens in the synaptic bulb as the calcium voltage gates open? - CORRECT ANSWER Ca2+ floods in, stimulating the vesicles to move to the membrane of the presynaptic bulb
Which chemical is held in the vesicles? - CORRECT ANSWER Acetylcholine (a neurotransmitter)
Define the term exocytosis - CORRECT ANSWER The release of the acetylcholine into the synaptic cleft. This then diffuses across the synapse.
What causes the sodium channel to open on the postsynaptic neurone? - CORRECT ANSWER Acetylcholine bonding to receptors on sodium voltage gate.
What happens to the acetylcholine after the sodium channel opens? - CORRECT ANSWER Broken down by acetylcholinesterase into ethanoic acid and choline. This is then reabsorbed by the presynaptic neurone and reformed into acetylcholine.
What does EEG stand for? - CORRECT ANSWER Electroenchephalogram [Show Less]