Responses to Stimuli
Structures for Response
Chemical or hormonal system, nerve and sense organ system, muscular, skeletal and an immune system.
Responses in Flowering Plants
Tropism: Growth in response to a stimulus
Phototropism: In response to light
- Roots are negatively phototrophic
- Shoots are positive
Geotropism: In response to gravity
- Roots are positive
- Shoots are negative
Thigmatropism: In response to touch
Hydrotropism: In response to water
Chemotropism: In response to chemicals
Auxin
- A growth promoter
e.g. Indoleatic Acid (IAA)
Production sites; Is produced in the meristematic tissue of apical, lateral, and adventitious buds. As well as in Root tips
Functions and Effect
Auxin
- A growth promoter
e.g. Indoleatic Acid (IAA)
Production sites; Is produced in the meristematic tissue of apical, lateral, and adventitious buds. As well as in Root tips
Functions and Effect
- Stimulate cell elongation
- Stimulate cell division in meristematic tissue
- Formation of xylem and phloem cells
- Phototropism and geotropism
- At high concentrations particularly in the roots IAA can inhibit growth
Mechanism of Phototropism
Auxin concentration is higher on the shaded side which causes the cells to elongate so that the plant grows towards the source of light.
Uses of Plant Growth Regulators
- Rooting powders to stimulate roots to grow
- Synthetic man made weed killers
- Increase size of fruit
- Ethene is used to ripen fruit
Plant Adaptations
Anatomical Adaptations
- Part of the structure of the plant
- Epidermis has adapted to protect the plant e.g. bark, thorns, needles and stinging hairs. Thick waxy cuticle is an extra layer of protection against pathogens and a loss of water
- Guard cells to prevent excess loss of water
- Cacti have evolved to grow no leaves to prevent loss of water. Are green for photosynthesis. And have thorns to prevent animals from eating it.
- Some plants such as the evening primrose only open their flowers at night when pollinators are more active
Chemical Adaptations
- Corn lily produces cyclopamine which makes it poisonous to herbivores
- Alkaloids are compounds produced by many herbacious plants to protect theselve against animals and insects.
- Poison Ivy produces urushiol for protection
- Spotted knapweed is a weed which takes over an entire area when it grows, by producing a chemical called catechin.
Investigate the Effect of IAA Growth Regulator on Plant Tissue
1) Label petri dishes and test tubes 1-8, each of them will have a different concentration of growth regulator
2) Use syringe and add 10 millilitres of IAA into a bottle of 100 millilitres of water. Using a different dropper each time remove 10 millilitres from one bottle and add it to the next. Serial Dilution.
3) Fit acetate grid in the lid of each dish
4) Place 5 cress seeds along the grid line
5) Place filter paper on top of seeds
6) Use matching droppers to solution. Add 2 millilitres of each solution to each dish
7) Place cotton wool over each dish to absorb excess solution and pour the rest of each solution on each dish.
8) Place on lid and secure with adhesive tap
9) Stand dishes vertically on their edge so that roots will grow down.
10) Leave in incubator for 2 - 3 days
The Nervous System
- Divided into the central nervous system (CNS) and the peripheral nervous system (PNS)
CNS = Brain and Spinal cord
PNS = Nerves and Ganglia
Neuron: Specialised nerve cell which sends electrochemical impulses to a nerve cell/effector
Sensory Neuron
Carries impulses to the CNS
Dendrites: Receive neurotransmitters and send signals to the cell body
Axons: Carry impulses away from the cell body
The Cell Body: Contains nucleus and forms dendrites and axons
Myelin Sheath: Fat rich material which insulates the impulses, helps to transfer impulse more efficiently
Schwann Cells: Form the myelin sheath
Axon terminals: Produce neurotransmitter chemicals
Motor Neuron
Carry impulse away from the CNS to muscles and glands
Interneuron: Carries impulses within the CNS
Movement of Nerve Impulse
- Transmitted by ion movement
- Sodium ions rush into a neuron as a nerve impulse travels
- Ions pump out again and prepare for conducting the next impulse
Transmission
Synapse: Structure where two neurons come in close contact so that an impulse can transmit. Control the direction of the impulse so they only flow one way.
Neurotransmitter: Chemical released by neuron to transmit nerve impulse e.g. dopamine, acetylcholine
Events at the Synapse
1) Electrical signal arrives at a synapse and stimulates the release of a neurotransmitter chemicals. Neurotransmitters are produced in the synaptic vesicle.
2) Chemicals diffuse across the synaptic cleft
3) Enter the dendrites of the next neuron. Chemicals are broken down and the electrical signal is regenerated.
Reflex Actions
Involuntary response to stimuli
e.g. withdrawel effect - pulling hand away from hot object
1) Temperature receptors in the skin send signal to the spinal cord
2) Signal received by the interneuron
3) Motor neuron is stimulated so that it sends signal to the muscle to pull hand away.
The Spinal Cord
Spinal Nerves: Carry impulses to and from the spinal cord
Dorsal Root: Carries impulses to the spinal cord along sensory neurons.
Ganglion: Swellings which contain the cell body of sensory neurons
White Matter: Contains axons
Grey matter: Contains cell bodies
Central Canal: Contains cerebrospinal fluid
Ventral Root: Contains motor neurons which carry impulses away from the spinal cord through motor neurons
Central Nervous System
The Brain:
Protection: Skull, 3 membrane layers; meninges, between each layer is cerebrospinal fluid
Cerebrum: 2 cerebral hemispheres, functions in reasoning, memory, intelligence, problem solving, emotion.
Cerebellum: Back of brain. Coordination of movement.
Medulla Oblongata: Deep within the brain. Involuntary movement such as breathing and heart rate.
Hypothalamus: Centre of brain. Receives signals of body temperature, hunger and thirst. Secretes some hormones which control the pituitary.
Pituitary: Below hypothalamus. Secretes hormones.
Parkinson's Disease
Symptoms: Uncontrollable arm and leg tremor. Stiff and rigid body, difficulty walking, fixed stare.
Cause: Death of a specific group of neurons which produce dopamine
Prevention: Causes are unknown. However protection around pesticides e.g. mask and washing fruit and vegetables may help prevent it.
Treatment: Physiotherapy, Drugs such as levodopa
The Senses
Cornea: Allows light into the eye. Transpparent part of the sclera.
Conjunctiva: Covers sclera and cornea to protect eye against pathogens.
Ciliary body: Smooth muscles surrounding cells. Contract and relax to change lens shape.
Suspensory ligaments: Holds lens in place. Attaches to and surrounds cilliary body
Lens: Transparent. Focuses light on the retina
Blind spot: No light receptors. Where nerves converge and exit the eye
Optic Nerve: Carries light impulses to the brain
Retina: Site of rods (black and white) and Cones (colours)
Choroid: Heavily pigmented with melinin, absorbs light to prevent internal reflection
Sclera: White of the eye. Protects the eyeball
Vitreous Humour: Viscous liquid. Creates an outward pressure on sclera to keep shape
Aqueous Humour: Watery liquid. Gives shape to the front of the eye
Pupil: Hole at the iris centre which allows light in
Iris: Colour. Contracts to control the amount of light entering the eye
Outer ear: Picks up sound waves
Middle ear: Transfers soundwaves to middle ear
Inner ear: Functions in hearing and balance
Pinna: Channels sound waves to auditory canal
Eardrum: Vibrates in response to sound waves
Ossicles: Vibrates within the eardrum
Cochlea: Receives vibrations from the ossicles through the oval window. Filled with lymph. Sound waves pass through the lymph and stimulate the hair cells. Sends signals to auditory nerve.
Semi-circular canals/Vestibular apparatus: Balance, semi-circular filled with lymph and hair cells fluid moves with head to create sense of balance.
Auditor Nerve = Cochlea nerve + Vestibular nerve
Eustachian Tube: Part of the middle ear and connected to the throat. Equalises pressure between the middle ear and outer ear by swallowing.
Eustachian Tube: Part of the middle ear and connected to the throat. Equalises pressure between the middle ear and outer ear by swallowing.
Ear Disorders
Glue Ear = inflammation of the middle ear, occurs with colds and flu
Symptoms: Pain in the ear, muffled hearing, pus formation
Treatment: Decongestant ear drops/Grommet tube
The Endocrine System
Hormone: Chemical messenger produced by an endocrine gland. Goes directly into the bloodstream. Travels to target tissue to produce an effect.
Endocrine: Product into bloodstream
- Chemical messages
- Slow to bring about effect
- Affects a wide area
- Long lasting
Exocrine: Product into duct
- Electric
- Fast
- Targets specific areas
- Short lived
Endocrine Glands
Pituitary Gland: Controls many other endocrine glands. Located at base of the brain. Hypophyseal portal system links pituitary to hypothalamus. Releases ADH for osmoregulation.
Thyroid: Located at neck, produces thyroxine which controls the rate of metabolism.
Parathyroid Glands: 1 at each corner of the thyroid. Parathormone increases calcium levels in the blood.
Thymus Gland: Part of the immune and endocrine system. Thymosine hormone, stimulates T cells to mature. Becomes smaller in adults.
Pancreas: Located in abdomen. Islets of Langerhans produce insulin. Insulin stimulates cells to take in more glucose so that glucose levels decrease in the bloodstream.
Adrenals: On top of kidneys. Produces adrenaline, which increases bloodflow to brain, lungs, heart and skeletal muscles. Decreases bloodflow to intestines and other areas of the body not involved in fight or flight.
Testes: Produce testosterone which bring about male sexual characteristics
Ovaries: Oestrogen and progesterone. Female sexual characteristics.
Growth Hormone
Deficiency Symptoms: Dwarfism, bones don't grow to their normal length
Corrective measure: Child given growth hormone throughout childhood
Excess Symptoms: Nearly always caused by pituitary tumour which leads to gigantism
Corrective Measure: Surgery to remove tumour
Control of Hormone Levels in the Blood
Negative feedback mechanism
Example: Thyroxine
- Pituitary gland produces hormone Thyroid - Stimulating Hormone. This is released into the blood and causes the thyroid gland to produce thyroxine
- If thyroxine levels in the blood are correct no more thyroxine is produced. Correct level of thyroxine causes a negative effect.
- If thyroxine levels are below normal TSH is made which causes more thyroxine to be produced. When thyroxine is normal again TSH is inhibited.
Hormone Supplements
Anabolic Steroids: Build up muscle mass in the body, reduce fat, speed up the repair of injuries and form stronger bones.
Insulin: Used for type 1 diabetes
Musculoskeletal System
Functions:
Shape: Gives the body its functional shape
Support: A rigid structure upon which many tissues are attached. Helps to keep tissues and organs in their correct positions.
Movement: Muscles use the bones of the skeleton as levers to create movement.
Protection: Protects internal organs of the body.
Manufacture of Blood: Bone marrow of long bones produce blood cells continuously.
Human Skeleton consists of the axial skeleton and appendicular skeleton
Axial Skeleton
Skull: Protects the brain, eyes and ears.
Facial Bones: Some fused and some freely movable joints. Mandible/Jaw bone functions in nutrition.
Vertebral Column: 33 Vertebrae divided into 5 regions, Cervical; 7 vertebrae, Thoracic;12 vertebrae, Lumbar; 5 vertebrae, Sacrum; 5 fused vertebrae, Coccyx; 4 fused vertebrae.
Between each vertebrae is discs of cartilage: Invertebral discs. Function in shock absorbtion and allow small movement between the vertebrae.
Rib Cage and Sternum: 12 pairs of ribs, True ribs: 7 directly attached to the sternum. False ribs; 3 attached to sternum by cartilage only. Floating ribs; 2 which do not attach to the sternum.
Appendicular Skeleton
Pectoral and pelvic girdle + the limbs
Pectoral Girdle: Scapula (shoulder blade) and Clavicle (collar bone). Connects the upper arm to the axial skeleton.
Pelvic Girdle: Gives strength and support to the body and provides movement for the lover part o the body.
Limbs: Also known as appendages.
Structure of a Long Bone
Periosteum: Outer covering of the bone containing fibres and blood vessels. Ligaments and tendons attach to it.
Diaphysis: Long extended part of the bone. Gives strength and length to the bone.
Compact Bone: Dense connective tissue composed of calcium salts and magnesium salts. Salts are secreted by osteoblasts and calcium salts are taken away by osteoclasts. Gives bone its strength and rigidity, Supplied by nerve fibres, blood vessels and collagen tissue throughout its structure.
Spongy bone: Composed of bars and plates separated by irregular spaces in between. Bone marrow tissue can be found in the spaces between the bars. Provides strength, support and rigidity to the bone.
Medullary Cavity: Composed of red marrow and yellow marrow. Red marrow is responsible for producing blood cells such as red blood cells, white blood cells and platelets.
Yellow marrow is composed of adipose tissue for the storage of lipids.
Cartilage: Functions in shock absorption and providing friction free movement.
Joints
- Location where two or more bones make contact with each other.
Immovable Joints: Joints that don't allow movement, for example the fused bones in the skull.
Slightly Movable: Permit a small amount of movement for example between each vertebrae. Bones are held together by muscle and ligaments.
Freely Movable Joints: Also known as sinovial joints. Contains sinovial fluid to provide friction free movement and is secreted by the sinovial membrane. Entire joint is enclosed with a fibrous capsule. Thin layer of cartilage to further allow for friction free movement and shock absorption. Two types of sinovial joints 1) Hinge joints e.g. elbow and knee 2) Ball and socket joints e.g. hip and shoulder joints.
Disorders of the Musculoskeletal System
Arthritis
- Painful inflammation of the joints caused by wear and tear/Immune reaction
- Treatment is anti inflammatory drugs or in severe causes surgery is performed to replace the joint e.g. hip replacements
Ligaments and Tendons
Ligaments: Join bone to bone. Type of connective tissue composed of collagen fibres. Keep joints stable and prevent excessive movement in the joints. Are slightly elastic however if stretched too far they can become ruptured or tear.
Tendons: Join muscles to bones. Type of connective tissue composed of collagen. Stretch to a certain extent to allow muscle to contract more forcibly.
Muscles
Skeletal Muscles: Composed of muscle fibre cells which are filled with the proteins actin and myosin.
Skeletal muscles usually come in Antagonistic Muscle Pairs; two muscle which have opposite effects to each other. e.g. Triceps and Biceps.
Biceps = Flexor; flexes the arm and closes the elbow joint
Triceps = Extensor; extends the arm or opens the joint
Development, Growth and Renewal of Bones
Osteoblasts: Produce and lay done new bone
Osteoclasts: Digest and remove old bone
Killer T Cells
- Kill body cells which are infected with a virus, abnormal, cancerous or damaged.
- They are first activated by a Helper T cell.
Immunisation: The protection against pathogens or the toxins of those pathogens through vaccination or by injection of antibodies or antidotes.
Shape: Gives the body its functional shape
Support: A rigid structure upon which many tissues are attached. Helps to keep tissues and organs in their correct positions.
Movement: Muscles use the bones of the skeleton as levers to create movement.
Protection: Protects internal organs of the body.
Manufacture of Blood: Bone marrow of long bones produce blood cells continuously.
Human Skeleton consists of the axial skeleton and appendicular skeleton
Axial SkeletonSkull: Protects the brain, eyes and ears.
Facial Bones: Some fused and some freely movable joints. Mandible/Jaw bone functions in nutrition.
Vertebral Column: 33 Vertebrae divided into 5 regions, Cervical; 7 vertebrae, Thoracic;12 vertebrae, Lumbar; 5 vertebrae, Sacrum; 5 fused vertebrae, Coccyx; 4 fused vertebrae.
Between each vertebrae is discs of cartilage: Invertebral discs. Function in shock absorbtion and allow small movement between the vertebrae.
Rib Cage and Sternum: 12 pairs of ribs, True ribs: 7 directly attached to the sternum. False ribs; 3 attached to sternum by cartilage only. Floating ribs; 2 which do not attach to the sternum.
Appendicular Skeleton
Pectoral and pelvic girdle + the limbs
Pectoral Girdle: Scapula (shoulder blade) and Clavicle (collar bone). Connects the upper arm to the axial skeleton.
Pelvic Girdle: Gives strength and support to the body and provides movement for the lover part o the body.
Limbs: Also known as appendages.
Structure of a Long Bone
Periosteum: Outer covering of the bone containing fibres and blood vessels. Ligaments and tendons attach to it.Diaphysis: Long extended part of the bone. Gives strength and length to the bone.
Compact Bone: Dense connective tissue composed of calcium salts and magnesium salts. Salts are secreted by osteoblasts and calcium salts are taken away by osteoclasts. Gives bone its strength and rigidity, Supplied by nerve fibres, blood vessels and collagen tissue throughout its structure.
Spongy bone: Composed of bars and plates separated by irregular spaces in between. Bone marrow tissue can be found in the spaces between the bars. Provides strength, support and rigidity to the bone.
Medullary Cavity: Composed of red marrow and yellow marrow. Red marrow is responsible for producing blood cells such as red blood cells, white blood cells and platelets.
Yellow marrow is composed of adipose tissue for the storage of lipids.
Cartilage: Functions in shock absorption and providing friction free movement.
Joints
- Location where two or more bones make contact with each other.
Immovable Joints: Joints that don't allow movement, for example the fused bones in the skull.
Slightly Movable: Permit a small amount of movement for example between each vertebrae. Bones are held together by muscle and ligaments.
Disorders of the Musculoskeletal System
Arthritis
- Painful inflammation of the joints caused by wear and tear/Immune reaction
- Treatment is anti inflammatory drugs or in severe causes surgery is performed to replace the joint e.g. hip replacements
Ligaments and Tendons
Ligaments: Join bone to bone. Type of connective tissue composed of collagen fibres. Keep joints stable and prevent excessive movement in the joints. Are slightly elastic however if stretched too far they can become ruptured or tear.
Tendons: Join muscles to bones. Type of connective tissue composed of collagen. Stretch to a certain extent to allow muscle to contract more forcibly.
Muscles
Skeletal Muscles: Composed of muscle fibre cells which are filled with the proteins actin and myosin.
Skeletal muscles usually come in Antagonistic Muscle Pairs; two muscle which have opposite effects to each other. e.g. Triceps and Biceps.
Biceps = Flexor; flexes the arm and closes the elbow joint
Triceps = Extensor; extends the arm or opens the joint
Development, Growth and Renewal of Bones
Osteoblasts: Produce and lay done new bone
Osteoclasts: Digest and remove old bone
- Development: Cartilage is slowly converted into bone in a process called ossification; Laying down new bone material by osteoblasts.
- Growth: In children and adolescents. A Growth Plate remains as cartilage between the epiphysis and the diaphysis which allows growth and will slowly disappear through ossification.
- Renewal: Bone is continually broken down and built up. Stress caused by injury or weight bearing will cause the bone to be laid down thinner.
Parathormone: Hormone which stimulates the removal of calcium from the bone = Stimulates osteoclasts.
Calcium: Is needed to keep the bones strong
The Defence System
The General Defence System
The Skin:
-Forms a physical barrier against pathogens
-Sweat and sebum secreted contains chemicals to break down pathogens
-Blood clotting prevents pathogens from entering open wounds
Mucous Membranes:
-Line the respiratory tracts, mucous traps microorganisms or debris and cilia move the mucous towards the pharnyx where it is swallowed. Coughing can spead up this process.
-HCL in the stomach kills pathogens
-Lining of the reproductive tracts e.g. vagina has a low pH to kill microorganisms
Phagocytosis
-Phagocytes are white blood cells which recognise, engulf and destroy bacteria. They accumalate at the site of an infection.
Fever
-Chemicals are released which causes the hypothalamus to increase body temperture. The temperature increase interfers with the enzymes in viruses and bacteria which prevents them from reproducing.
Defence Chemicals
-Lysozyme is present in tears, it kills bacteria.
-Infection or foreign material causes cells to release histamine, which dilates the blood vessels and causes more white blood cells to accumulate at the site.
-Virus infected cells release interferons which alert the other cells to be more resistent to proteins entering the cell.
-Liver produces complement proteins which assist the immune system in ridding the body of a pathogen
Specific Defence System (Immune System)
Organs Involved:
- Spleen
- Thymus
- Lymph Nodes
Antigens: Surface proteins which cause the production of antibodies
Anitbodies: Proteins produced ny lymphocytes in response to antigens
Monocytes
- Type of white blood cell
- Produced in the bone marrow and can develop into many different types of white blood cells. Most common = Macrophages
- Macrophages engulf bacteria and viruses, digest them within the cell and display the broken down pieces of the pathogen (antigen) on the surface of the cell.
- Macrophages can release cytokines which is a chemical that stimulates other immune cells into action.
Lymphocytes
- Produced in the bone marrow and are the main components of the human immune system.
- Interact with the foreign particles placed on the surface of the macrophages.
- Interact with the foreign antigens placed on the surface of macrophages to stimulate the producion of antibodies against a specific antigen.
- Each B cell produces only one type of antibody.
Plasma B Cells
- Mature in the spleen and lymph nodes
- After interacting with the antigens they multiply and produce a specific type of antibody against the antigen.
- Called the Primary Response and can take up to 2 weeks to occur.
- Continue to produce antibodies until the antigen is eliminated.
Memory B Cells
- After antigen is eliminated most of the plasma B Cells die off
- A small number survive to become memory B Cells
- If the body is infected by the same antigen the memory B Cells can produce a large amount of antibodies in a short space of time.
- This is called a secondary response, antibodies can be produced in a shorter space of time, and in larger numbers.
Antigen-Antibody Binding
- Specificity of antibodies
- Shape of the antibody is complementary, one antibody can only bond with one type of antigen.
- Bonding the antibody to the antigen (surface of the pathogen) highlights the foreign body for destruction by macrophages.
- Cytokines alert lymphocytes and monocytes to eliminate a pathogen.
- Spleen
- Thymus
- Lymph Nodes
Antigens: Surface proteins which cause the production of antibodies
Anitbodies: Proteins produced ny lymphocytes in response to antigens
Monocytes
- Type of white blood cell
- Produced in the bone marrow and can develop into many different types of white blood cells. Most common = Macrophages
- Macrophages engulf bacteria and viruses, digest them within the cell and display the broken down pieces of the pathogen (antigen) on the surface of the cell.
- Macrophages can release cytokines which is a chemical that stimulates other immune cells into action.
Lymphocytes
- Produced in the bone marrow and are the main components of the human immune system.
- Interact with the foreign particles placed on the surface of the macrophages.
- B Cells
- Interact with the foreign antigens placed on the surface of macrophages to stimulate the producion of antibodies against a specific antigen.
- Each B cell produces only one type of antibody.
Plasma B Cells- Mature in the spleen and lymph nodes
- After interacting with the antigens they multiply and produce a specific type of antibody against the antigen.
- Called the Primary Response and can take up to 2 weeks to occur.
- Continue to produce antibodies until the antigen is eliminated.
Memory B Cells
- After antigen is eliminated most of the plasma B Cells die off
- A small number survive to become memory B Cells
- If the body is infected by the same antigen the memory B Cells can produce a large amount of antibodies in a short space of time.
- This is called a secondary response, antibodies can be produced in a shorter space of time, and in larger numbers.
Antigen-Antibody Binding
- Specificity of antibodies
- Shape of the antibody is complementary, one antibody can only bond with one type of antigen.
- Bonding the antibody to the antigen (surface of the pathogen) highlights the foreign body for destruction by macrophages.
- T Cells
- Produced in the bone marrow and mature in the thymus
Helper T Cells
- Signaling cells which help organise the immune system response against a pathogen.
- Interacting with a macrophage presenting antigens causes the Helper T to release cytokines.
- Cytokines alert lymphocytes and monocytes to eliminate a pathogen.
Killer T Cells- Kill body cells which are infected with a virus, abnormal, cancerous or damaged.
- They are first activated by a Helper T cell.
- Release perforins which create holes in the cell membranes.
Suppressor T Cells
- Keep the immune response under control.
- Stop the immune response after the pathogen is eliminated.
- Maintain tolerance to self-antigens, which are proteins present on the surface of normal cells. Ensures the body doesn't start attacking its own tissues.
Memory T Cells
- T cells which survive in order to create a fast secondary response if the antigen enters the body again.
- Give long lived immunity against a particular pathogen; usually survive in the spleen.
Suppressor T Cells
- Keep the immune response under control.
- Stop the immune response after the pathogen is eliminated.
- Maintain tolerance to self-antigens, which are proteins present on the surface of normal cells. Ensures the body doesn't start attacking its own tissues.
Memory T Cells
- T cells which survive in order to create a fast secondary response if the antigen enters the body again.
- Give long lived immunity against a particular pathogen; usually survive in the spleen.
Induced Immunity
Stimulation of monocytes and lymphocytes to get rid of a specific antigenImmunisation: The protection against pathogens or the toxins of those pathogens through vaccination or by injection of antibodies or antidotes.
- Active Immunity; Production of antibodies by lymphocytes in response to a specific antigen
Natural Active Immunity: Lymphocytes produce antibodies in response to a pathogen infecting the body
- Memory B Cells and T Cells can react quickly and produce antibodies in large aounts if the body is infected again.
Artificial Active Immunity: Lymphocytes produce antibodies in response to an antigen introduced by a vaccine.
- Vaccination is an administrated non-disease causing dose of a pathogen or part of a pathogen. It causes active immunity.
- A weakened dose but not a small dose.
- Passive Immunity: Transfer of antibodies from one organism to the other.
Natural Passive Immunity: When a baby receives antibodies from its mother through the placenta and breast milk.
Artificial Passive Immunity: When an injection of antibodies made in another organism is administrated.
- Antibodies must be injected, they would be digested if given by mouth.
* Passive immunity is short lived as they ae not made by the persons own lymphocytes and therefore no memory cells can be produced.
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