-
what is the function of the root hair cell?
absorption of water and minerals from soil to plant
-
what are the adaptations of the root hair cell?
- - large in number with finger like projection (to increase surface area for maximum absorption)
- - full of mitochondria (for energy for ion mineral absorption by active transport)
- - thin walls (shorter distance faster diffusion)
- - large central vacuole (for water absorption by osmosis)
-
what is the function of the xylem?
- - support plant
- -transport water
- - transport minerals
-
what are the adaptations of the xylem?
- - pits (for lateral movement)
- - no end wall, no cytoplasm, no nucleus (to prevent resistance of movement of water and molecules)
- - thin walls (to increase surface area for more water and minerals to pass)
- - lignified walls (to give plant support)
-
what is the function of cilliated epithilial cells?
- goblet cells release sticky mucus to trap dust and bacteria
- cillia beats or wasps sticky mucus up the throat
-
what are the adaptations of the muscle cell?
- -some of the cytoplasm is modified into contractile filament
- - respires aerobically and anaerobically
- -contains glycogen store
as energy source - - full of mitochondria
-
what is the tail of the sperm called?
flagellum
-
what is the digestive enzyme in the sperm called?
acrosome
-
what is the ovum's jellycoat made of?
protein
-
what are the three types of movement in and out of the cell?
- Osmosis
- diffusion
- active transport
-
what is diffusion?
random movement of gasses and liquids from high concentration to low concentration areas until equilibrium
-
what is osmosis?
the diffusion of water molecules from high water potential regions to low water potential regions through a partially permeable membrane
-
what is active transport?
the movement of molecules and ions through the cell membrane from regions of low concentration to regions of high concentration using energy from respiration and a specific protein carrier
-
what happens to an animal cell in distilled water?
- cell gains water
- by osmosis
- from areas of high water potential to low water potential
- through a partially permeable membrane
- cells becomes turgid
- cell bursts due to absence of cell wall
-
what happens to animal cell in concentrated solution?
- cell loses water
- by osmosis
- from areas of high water potential to areas of low water potential
- through a partially permeable membrane
- cell becomes flacid
-
what is the difference between active and passive transport?
active transport requires energy from respiration passive transport occurs naturally without energy
-
what happens to a plant cell in a dilute solution?
- plant cell gains water
- by osmosis
- from areas of high water potential to areas of low water potential
- through a partially permeable membrane
- cell becomes turgid
- cell doesn't burst due to the presence of cell wall
-
what happens to a plant cell in a concentrated solution?
- cell loses water
- by osmosis
- from areas of high water potential to areas of low water potential
- through a partially permeable membrane
- cell becomes flacid
- cell membrane detaches from cell wall cell plasmolysis
- cell wilts
-
how does root hair cell absorb minerals?
how are glucose and amino acids absorbed?
- by active transport
- from areas of low concentration to areas of high concentration
- through cell membrane
- using energy from respiration
- and specific protein carrier
-
explain why enzymes are specific?
explain why enzymes have a specific shape?
- every enzyme has specific active site that fits with its substrate like lock and keyenzyme and substrate are complimentary to each other
-
what is an enzyme?
biological catalyst that speeds up chemical reaction without being changed
-
what factors affect enzymes?
-
describe enzyme at temperature 10
- less active
- less kinetic energy
- less collision
- less chance of successful collision
- less formation of enzyme substrate complex
-
describe enzyme at temperature 35
- more active
- more kinetic energy
- more collision
- more chance of successful collision
- more formation of enzyme substrate complex
-
describe enzyme at temperature 70
- enzyme has denatured
- active site has changed shape
- enzyme and substrate no longer fit like lock and key
- enzyme and substrate are no longer complimentary
-
what are the benefits of biological washing powder?
- - saves electricity due to needing a low temperature of 35
- - can be reused
- - avoid damage done by boiling and rubbing
-
what are the advantages of pectinase?
- - more juice
- - clearer juice
- - faster extraction
- - sweeter juice
-
what affects diffusion?
- - temperature
- - surface area
- - current
- - gas pressure
- - size
-
what is the digestive system?
set of organs working to ingest food, digest it, absorb it, assimilate it and egest undigested food.
-
egestion vs excretion?
- egestion is the removal of undigested food
- excretion is the removal of toxins and waste substances (anything but solid feaces)
-
what is ingestion?
the taking in of substances into the body through the mouth
-
what is digestion?
the breaking down of large insoluble complex molecules into small simple soluble ones
-
what is absorption?
the movement of digested food through the small intestine wall into the blood
-
what is assimialtion?
the movement of digested food from blood to the cell to become part of it
-
what is egestion?
removal of undigested food
-
what is peristalsis?
the rhythmic contraction of muscles to move food along the alimentary canal
-
what is found in the mouth?
- -tongue
- -teeth
- -salivary gland
-
what is the function of the tongue?
- -organ of taste
- -mixes food with saliva
- -moves food between the teeth
-
what is the function of the teeth?
- -break down food into smaller pieces to increase surface area for enzymes to work best(mechanical digestion)
- -facilitate swallowing
-
what is the function of the salivary glands?
- secrete saliva containing
- -bicarbonate (to neutralise mouth acidity)
- -mucus (to soften and moisten food to be easily swallowed)
- -amylase (to break down starch into maltose)
-
what is found in the stomach?
- -mucus (to protect stomach from HCl and pepsin)
- -HCl (keep ph acidic- activates pepsinogen - kills bacteria)
- -pepsin (breaks down proteins to amino acids)
-
what is the function of the liver in fat digestion?
- -secrete bile salt to emulsify fat into small fat droplets to increase surface are for lipase to break down fats to fatty acids and glycerol
- -secrete bile pigment to give feaces its colour
- -secretes bicarbonate to neutralize acidity from stomach
-
where is bile stored?
gallblader
-
what is the function of the pancrease during digestion?
- secretes pancreatic juice containing
- -lipase (to break down fats to fatty acids and glycerol)
- -trypsin (to break down proteins to amino acids)
- -amylase (to break down starch to maltose)
- -bicarbonate (to neutralize acidity)
-
what is the function of the intestinal juices?
- contain
- -maltase (to break down maltose to glucose)
- -pepsin (to break down proteins to amino acids)
- -lipase (to break down fats to fatty acids and glycerol)
-
describe cholera
- 1- bacteria in small intestine releases toxins
- 2- they stimulate small intestine walls too release chloride ions
- 3-the water potential in the small intestine decreases
- 4-so water moves by osmosis out of the cells into small intestine
- 5- resulting in dehydration-diarrhea- loss of salts -loss of water
-
what are the adaptations of the villi?
- -has lacteal(to absorb fatty acids and glycerol)
- -has capillaries(absorb amino acids and glucose)
- -thin epithelial walls (shorter distance faster diffusion)
- -digestive enzymes
- -microvilli (to increase surface area for max absorption)
- -mitochondria (for energy for active transport)
-
how does the liver regulate glucose levels?
- -if glucose levels are high pancrease receptors secrete insulin hormone to stimulate the liver to change glucose into glycogen to bring blood glucose levels back to set point (homeostasis)
- -if glucose levels are low pancrease receptors secrete glucagon hormone that stimulates the liver to convert glycogen into glucose to be used up by cells during respiration and bring blood glucose level back to set point (homeostasis)
-
how does the liver regulate amino acids level?
- liver assimilates amino acids to form new enzymes, hormones, antibodies, cells
- the excess amino acids are deaminated by removing the nitrogen containing part converting it into ammonia then into urea to be excreted
-
how is cholera treated?
- -antibiotics
- -oral rehydration therapy
-
what are the components of the blood?
- -RBCs
- -WBCs
- -platelets
- -plasma
-
what are the adaptations of the RBCs?
- -small (to pass through narrow blood capillaries)
- -elastic (to squeeze through narrow blood capillaries)
- -biconcave (to increase surface area to carry more o2)
- -no nucleus (for more space to carry more nucleus)
- made in bone marrow with life spam of 120 days
-
what is the function of WBC?
- -lymphocytes
- release antibodies
- that bind to the antigen as they are complimentary
- they immobilize the antigen
- prevent its spreading
- then burst it
- and collect it in lumps
- as vesicles
- -phagocytes
- engulf the vesicle
- the ingest it
- the release enzymes to digest it
-
what do platelets prevent?
- blood loss
- microbe infection
-
what is the function of the platelets?explain
- blood clotting
- platelets are stimulated
- thrombin enzyme catalyzes soluble fibrinogen to insoluble fibrin
- they form a mesh
- to trap RBCs
- and form new skin
-
what are the adaptations of the artery?
- -thick walls
- -narrow lumen
- -elastic walls
- -muscle ring
-
what are the adaptations of the veins?
- -valves
- -thin walls
- -wide lumen
-
what are the adaptations of the capillaries?
- gaps(to allow tissue fluid to pass)
- thin walls
- large in number
-
-
what is the effect of exercise on the heart muscle during exercise?
- 1 oxygen demand increases
- 2 heart pumps more blood
- 3 to carry more oxygen and glucose
- 4 for more aerobic respiration
- 5 for more energy release
- 6 for more muscle contraction
- 7 at a point of vigorous exercise
- 8 heart muscle can't supply the muscles with enough oxygen
- 9 so muscle respires anaerobically
- 10 releasing lactic acid
- 11 which will be oxidized in the liver
- 12 to become CO2 and H2O
-
which chamber has the thickest walls?
left ventricle
-
which blood vessle pumps blood at highest blood pressure?
Aorta
-
which heart chamber creates the highest blood pressure?
left ventricle
-
which blood vessel has highest concentration of oxygen?
pulmonary vein
-
what stimulates the brain to increase breathing rate during exercise ?
the increase if carbon dioxide concentration in the blood
-
which two blood vessels bring deoxygenated blood into the heart?
- superior vena cava
- inferior vena cava
-
which blood vessel brings deoxygenated blood from the heart to the lungs?
pulmonary artery
-
blood vessel that bring oxygenated blood to the heart?
pulmonary vein
-
blood vessel that pumps blood to the body?
aorta
-
blood vessle that sends oxygenated blood to the liver
hepatic artery
-
which blood vessel brings back deoxygenated blood from liver?
hepatic vein
-
blood vessle that sends oxygenated blood to the kidneys
renal artery
-
blood vessle that brings back deoxygenated blood from the kidneys
renal vein
-
artery that brings the heart oxygen and glucose?
coronary artery
-
what is dual circulation?
the blood goes through the heart twice in one complete circuit around the body
-
why is dual circulation important?
- -allows different blood pressures
- -prevents the mixing of oxygenated and deoxygenated blood
- -allows high blood pressure
- -allows high metabolic activity in mammals
-
what are the adaptations of the heart?
- -septum (to prevent mixing of oxygenated and deoxygenated blood)
- - thick cardiac muscular walls
- -thicker left ventricle (to be able to pump blood to the whole body)
- -pacemaker(that sends impulses from the brain for the heart to contract)
- -valves (to prevent blood backflow)
-
what happens to cause the bicuspid valve to open?
- left atrium fills with blood
- left atrium contracts bicuspid valve opens
- semilunar valve closes
-
what happens when the semilunar valves cpen?
atrioventricular valves (bicuspid and tricuspid)valves close
-
what do atrioventricular valves do?
prevent the backflow of blood from ventricle to atrium
-
what do semilunar valves fo?
prevent backflow of blood from arteries to ventreicles
-
how to measure pulse rate?
- -measure pulse from wrist and repeat a couple of times
- -use stethoscope to hear the sound of the valves closing
- -ECG every peak is a pump
-
what causes CHD?
- -coronary artery is blocked due to fat deficit
- -so heart doesn't get enough oxygen and glucose
- -so heart doesn't respire aerobically but respires anaerobically
- -causing lactic acid build up
- -causing a thrombus (heart attack)
-
what are the causes of CHD?
- excessive fat intake
- excessive salt
- excessive sugar
- smoking
- genetics
-
what is respiration?
chemical reaction that changes nutrient molecules in living cells to release energy using oxygen
-
word and symbolic equation of aerobic respiration?
- oxygen + glucose---> energy+ carbon dioxide+ water
- 6O2 + C6H12O6 --->E + 6CO2 + 6H2O
-
what is the importance of energy?
- -protein synthesis
- -maintain metabolic reaction
- -keep body temperature
- -active transport
- -nerve impulse
- -muscle contraction
-
what is anaerobic respiration?
release of low amount of energy due to incomplete breakdown of glucose in the absence of oxygen
-
word equation of anaerobic respiration?
glucose ----> lactic acid + small amount of energy
-
inspired air vs exhaled ?
- -78% nitrogen in -78%nitrogen out
- -0.04% CO2 in -4% CO2 out
- -21% O2 in -16%O2 out
-
how does zygote become an embryo?
- -after fertilization zygote is formed
- -zygote divides by mitosis to form a ball of cells called embryo
- -embryo moves by cillia and peristalsis to be implanted in uterine lining
-
what is fertilization?
fusion of the nuclei of the male haploid sperm and the nuclei of the female haploid ova to form a diploid zygote
-
what does taking testosterone do?
- -increase lung capacity
- -increase muscle growth
- -increase bone and limb growth
-
how can the baby get AIDS if the mother is diseased?
- -through the placenta
- -during birth
-
explain the menstrual cycle
- -from pituitary gland in brain
- *FSH
- stimulates maturation and development of follicle
- stimulate oestrogen
- -from ovary grafian follicle
- *oestrogen
- inhibit FSH
- to stop follicle development
- stimulated uterine lining repair
- stimulate LH
- -from pituitary gland in brian
- *LH
- stimulate ovulation
- stimulate progestrone
- -from yellow body (corpus luteum)
- *Progestrone
- inhibit FSH
- inhibit LH
- maintains thick endometrium
- stops menses
- stimulates mammary gland for lactation
-
how does zygote form?
- -testes and ovary reduction and division by meiosis to form haploid gametes
- -the haploid nuclei of the ova fuses with haploid nuclei of sperm to form diploid zygote
-
function of scrotum?
holds testes outside the body as sperm needs lower than body temp to be produced
-
function of cervix?
- -secretes muccus to create medium for sperm
- -dilates during labour
-
how is HIV transmitted?
- - sexual intercourse (exchange of bodily fluid)
- - blood transfusion
- - infected needle
- - personal belongings
-
how to prevent STI
- -use a condom
- -use femdom
- -test before sexual intercourse
-
Vagina?
- -secretes muccus to facilitate penis entry
- -secretes acid to kill bacteria
- -site of speerm deposition
-
placenta function
- -excretion
- -nutrition
- -prevent mixing of fetal and maternal blood
- -gas exchange
- -secretes progestrone
-
oviduct?
site of fertilization
-
sperm pathway
- -produced in tested
- -stored in epididymis
- -spermduct
- -prostate gland
- -ejaculated out of penis
-
what does the seminal fluid out of the prostate gland contain?
-
what is the condom?
rubber sheath inserted over the male penis to prevent the deposition of the sperm in the femal's vagina
-
amniotic fluid location and importance
- *amniotic sac
- -maintains suitable temperature for the fetus
- -sterlizes pathway
- -acts as lubricant
- -facilitates the movement of the fetus
-
-
how long does the sperm stay alive?
3 days
-
what hormone is responsible for puberty in males?
testosterone
-
what hormone is responsible for puberty in females ?
oestrogen
-
Excretion?
Removal waste products of metabolism, excess substance and toxic material
-
Importance of excretion?
- Avoid accumulation of waste
- Removal of toxics products of metabolism
- Homeostasis to remove excess
- Osmoregulation
-
Starch test
- -iodine solution
- Turns from yellowish brown to blue black
-
Simple sugars test
- Benedict’s solution
- From blue Turns GYOB
- Green
- Yellow
- Orange
- Brick red
-
Protein test
- Biuret
- Turns from blue to lilac
-
Fats/Lipids test
- Ethanol
- Turns turbid and milky
-
Photosynthesis definition
The process in which light energy is trapped by chlorophyll to convert carbon dioxide and water to oxygen and glucose
-
Importance of glucose
- Respiration
- Converted to starch to be stored in root
- Converted to sucrose to be carried to parts that don’t make own food
- Converted to cellulose to make cell wall
-
Photosynthesis in high light
Faster rate
-
Photosynthesis in low light
Lower rate compensation point rate of respiration is equal to rate of photosynthesis so no gasses produced
-
Upper and lower epidermis
- Transparent to let light through
- Lens to bend light
- Cuticle to prevent water loss
-
Which cells perform most photosynthesis
- 1 palisade
- 2 spongy
- 3 Guard call
-
Why do spongy have air spaces
To allow for circulation and diffusion of gasses
-
Eutrophication
- Excess nitrogen fertiliser is used and washed away by rain
- Causing increase in growth of plants by the water Algae bloom
- Algae bloom blocks light from reaching aquatic plants preventing them prim photosynthesis causing them to die
- Decomposers increase and consume all oxygen in the water by aerobic respiration killing aquatic organisms
-
Importance of water in plants
- Acts as solvent
- Activates enzymes
- Forms Part of cytoplasm and vacuole
- Keeps cell turgid
- Photosynthesis
-
Water pathway in plant
Water is absorbed by root hair cell then enters the cortex of the root then the vascular bundle of the root then carried by the the xylem of the root to the xylem of the stem to the xylem of the leaf to reach mesothelioma layer the. Transpired out of the stomata by evaporation and diffusion
-
What is transpiration ?
The evaporation of water at the surface of mesophyll cell followed by loss of water vapour from the plant leaves through the stomata
-
Why does air current increase transpiration rate?
As air current causes water vapour to move from the surface of the leaf giving more chance for water vapour to move outside the leaf.
-
Internal factors increasing transpiration rate?
- Increase in number of stomata
- Higher exposed surface area
- Thin cuticle
- Increase air spaces
-
Experiment to show water is lost from shoot?
- Cover plant shoot with polythene bag
- Water droplets condense on the surface of the inner wall of the bag
- Anhydrous copper sulfate turns from white to blue
-
What is wilting?
- Water loses more water then it gains
- Transpiration rate is higher than water uptake rate
-
What is translocation?
Movement if sucrose and amino acids from regions of storage and production to regions of utilisation
-
What is stroke volume ?
Amount of blood pumped out of the left ventricle per beat
-
What is cardiac output and how is it calculated?
- Amount of blood pumped out of left ventricle per minute
- Stroke volume x heart rate = cardiac output
-
What is the kidney function excretion process?
- -Blood enters renal artery at high blood pressure contains oxygen glucose amino acids salts water urea and uric acid
- -ultra filtration takes place at the beginning of the nephron sending back insoluble substances such as proteins, plasma proteins and RBCs
- -filtrate passes through contains soluble substances
- - selective reabsorption takes place sending back glucose amino acids some salts and some water back to the blood
- - urine is formed at the end of the nephron contains urea uric acid salt and water
- -urine passes through the ureter to the bladder and out of the body through the urethra
-
What is a hormone?
A chemical substance produced by a gland and carried by the blood which alters the activity of one or more target organs
-
Where is the adrenaline hormone secreted and what is an alternative name for it?
- Adrenal glands
- 3F hormone (fight fright flight)
-
What are the effects of Adrenalin?
- Increase blood pressure
- Increase heart rate
- Increase breathing rate
- Dilated pupils
- Constricts blood vessel of skin and digestive system to increase blood flow to muscles
-
Brain and spinal cord matters?
- Brain
- Outer layer : grey matter
- Inner layer: dark matter
- Spinal cord
- Outer layer: white matter
- Inner layer: grey matter
-
Importance of myelin sheath?
- Prevent leakage of impulse
- Faster impulse
- Protects neurons
- Acts as insulator
-
Sensory neuron
- Sends impulse from sensory organ(receptor) to brain
- - short axon
- -long dendrite
- -cell body in the middle
-
Motor neuron
- Sends impulses from brain to effector
- -long axon
- -short branched dendrite
- -cell body at the end
-
What is a nerve impulse?
Wave of electrical pulse that travels in the nerve fibres at very high sped and in one direction only
-
What is the synapse?
Junction between 2 neurons that insures one directional flow
-
What happens to the muscle in the eye in bright and dim light?
- Dim light:
- radial contract
- Circular relax
- Bright light:
- Radial relax
- Circular contract
-
What happens to muscle and ligaments in the eye when an object is near or far?
- Near
- Ciliary contract
- Suspensory slacken
- Far
- ciliary contracts
- Suspensory tense
-
Nervous v hormone
Made of/transmitted in and by/ velocity/ effect time/ place of effect
- Nervous
- Made of Neurons
- Transmitted by electrical impulses in the nerves
- Very high speed
- Short term
- Localised
- Hormone
- Made of glands
- Transmitted by blood in form of chemicals
- Slower speed
- Wide spread
-
Pathway of reflex arc
- Pain receptor
- Sensory neuron
- Relay neuron in spinal cord
- Motor neuron
- Effector
-
Importance of reflex action
- Survival value
- Learning valuable skills
-
Reflex action?
Rapid Involuntary response to stimuli
-
Positive phototropism
- Auxins are plant growth hormone
- Found at the top of the shoot
- Destroyed by light
- Diffuse to the darker side
- Stimulate elongation
- Towards sunlight
-
Positive gravitopism
- Auxins are plant growth hormones
- Found at the top of the root
- Diffuse to the lower side
- Inhibit elongation
- grow towards gravity
-
Negative gravitropism
- Auxins are plant growth hormones fl
- Found at the tip of the shoot
- Diffuse to the lower side
- stimulate elongation
- Away from sunlight
-
Negative phototropism
- Auxins are plant growth hormone
- found at the tip of the root
- Destroyed by light
- Diffuse to the darker side
- Inhibit elongation
- Away from sunlight
-
What is a sensory organ?
Organs that are a group of receptor that responds to specific stimuli
-
Importance of maintains internal environment
- Prevents damaging of cell membrane
- Enzyme at optimum temperature
- Prevent enzyme denature
- Allows High metabolic activity in mamals
-
What is the function of the optic nerve ?
Sensory nerve that transmits impulse from the light receptor to the brain
-
What is Meiosis?
Reduction and devision
-
Meiosis?
- 2 parents
- Formation of gametes
- Non identical
- Variation
-
Mitosis importance
- Growth
- Repair
- Replacement of worn out cells
- Skin grafts
-
Sepal function
Protects the flower
-
Unisexual v bisexual plants
- Unisexual needs cross pollination
- Bisexual can self pollinate
-
Pollination definition
Transfer of pollen grains from anther to stigma
-
Insect pollination
- -small in number of pollen
- -heavy pollen
- -stick stigma
- -Reproductive organs enclosed
- -guidelines
- -bright coloured petals
- -nectar
-
Wind pollinated
- -feathery sigma
- - anther hanging outside
- - large in number of pollen
- -light pollen
-
After pollination
Pollen lands on stigma then digs pollen tube in the style then reaches the ovary enters and fuses with the ovule to form zygote that divides by mitosis to form embryo
-
After fertilisation
- Ovary —-> fruit
- Ovule —-> seed
- Wall of ovary——> pericarp
- Wall of ovule ——> testa
-
Conditions of germination?
-
Cell wall function
- Keeps cell turgid
- Support
- Prevent bursting
-
Cell membrane function
- Surrounds cell components
- Controls what goes in and out of the cell
-
Nucleus function
- Controls cell activity
- Contains dna
-
Cytoplasm function
- Supports organelle
- Contain food store
-
Ribosome
Converts dna into protein protein synthesis
-
-
Chloroplast
Contains chlorophyll and enzymes
-
Vacule
- Contains ions
- Regulates water absorption
- Supports cell
-
What process moves oxygen into RBCs?
Diffusion
-
What divides by meiosis to form the plant gametes?
- Anther——> pollen grains
- Ovary——-> ovule
-
What is reproduction?
The ability of living organisms to produce new offsprings to preserve the species and prevent extinction
-
What is urea formed of?
Excess amino acids
-
In which part of the canal do both mechanical and chemical digestion take place?
Mouth
-
Why are x-rays dangerous on testes?
- Kills sperm
- Causes mutation
- Could pass off to offspring
- Could cause sterility
- Could damage the nucleus if the gametes
-
What does AIDS do to the immune system?
Kills lymphocytes
-
Inheritance definition
Passing of genes from generation to generation
-
Chromosome definition
Thread like structure if DNA contains genetic information in form of genes
-
Gene definition
A length of DNA that codes for protein
-
What is variation ?
A difference between two individuals of the same species
-
Factors affecting continuous variation
- Several pairs of alleles
- Environment
-
Example of continuous variation
-
Continuous variation
Intermediate between 2 extremes
-
Discontinuous variation definition
Limited number of distinct phenotypes with no extremes
-
What affects discontinuous variation?
- Not affected by environment
- 1 pair of allele only
-
What are examples if discontinuous variation?
- Tongue rolling ability
- Sex
- Blood group
-
What are Factors of mutation ?
- Chemical:
- Tobacco
- Mustard Gas
- Radiation:
- X-ray
- Gamma ray
- Cosmic ray
-
Chromosome mutation
- A part of chromosome is snapped and lost
- Decrease or increase in number of chromosome
- Change in 1 or more chromosome
-
Gene mutation
Change in an individual’s gene
-
Cause of genetic variation
- Meiosis
- Sexual intercourse
- Fertilisation
- Mutation
-
Mutation
Unpredictable change in base sequence if DNA, gene or chromosome that results in change of phenotype and variation
-
Why is insulin injected and not taken by mouth ?
As it is made of a protein and would be digested broken down to amino acids by pepsin if it was invested and wouldn’t be able to carry its function of stimulating ten liver to change glucose to glycogen
-
What does oral rehydration therapy contain?
- Glucose
- Water
- Ions
- Sodium
- Potassium
-
What is selection?
The process of choosing the best varieties that are well adapted and allow them to reproduce
-
Natural selection
- Don’t adapt—-> die
- Adapt—->survive—-> reproduce—-> pass allele to offspring ——> increase Fittnes
-
Plant selective breeding
- Remove anther of 1st selected plant before maturation to prevent self pollination
- Cover in plastic bag ti prevent any pollen from reaching stigma
- Collect pollen grains from 2nd selected flower after maturation
- Dust pollen grains of 2nd on the stigma of the 1st flower and allow pollination
- Select seeds and germinate
- Select offspring with desired characteristics and breed together
-
Animal selective breeding
- Select 2 parents with desired characteristics
- Cross and breed them together
- Chose 2 offspring’s with desired characteristics
- Cross and breed them together
- Repeat process over generations
- Till 100% offsprings have desired characteristics
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Microorganisms definition
Tiny organism only seen under microscope
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Disease definition
Disorder or malfunction in the body
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Pathogen definition
Microorganism that causes diseases
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Infection definition
The entry of a pathogen into the body
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Direct contact transmission? And ways
- Through bodily fluids (sexual intercourse)
- Contaminated needles
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Indirect contact ways of transmission
- Water
- Air
- Contaminated surfaces and food
- Animal waste
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Infectious diseases
Disease caused by pathogen and can be transmitted from one organism to the other
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Barriers against diseases
- Mechanical:
- Skin
- Hair in the nose
- Chemical:
- Mucus
- HCL
- Cells:
- Lymphocytes
- Phagocytes
- Vaccination:
- Injection of dead or dormant antigen to build immunity by memory cells
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Avoid spreading diseases
- Personal hygiene:
- Shower
- Brush teeth
- Wash hands before cooking and eating
- Sewage treatment:
- Remove urine faeces microbes toilet paper using proper method from sewage water
- Food:
- Cover food
- Avoid coughing
- Cool well
- Keep hair away from food
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What do we use to know how much energy is released from an animal for pyramid of biomass?
Calorometer
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From which cell does evaporation takes place during transpiration?
Spongy mesophyll
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movement meaning?
action done by organism or part of it that results in change of shape
-
sensitivity meaning?
the ability to sense and detect changes to the internal or external (stimuli) environment and respond
-
growth meaning?
permanent increase in size and dry mass by increase in cell size, number or both
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reproduction meaning?
process of making more of the same kind
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nutrition meaning?
taking in of nutrient containing energy for growth, repair and development
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classification meaning?
sorting living organism into groups according to their shared features
-
what is a species?
a group of organisms with common features and can bread together to produce offspring
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importance of classification?
- -facilitate study of living organisms
- -facilitate identification of living organism
-
what is binomial system?
- internationally agreed system in which the
- scientific name of an organism is made up of two
- parts showing the genus and species
-
classification levels from largest to smallest?
- kingdom
- phylum
- class
- order
- family
- genus
- species
-
how should the binomial name be written?
- the Genus beginning in capital letter
- the species in small
- in latin
- italic or underlined
-
scientific binomial name for humans?
- Homo sapiens
- (Homo) genus
- (sapiens) species
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vertebrae meaning?
living organism with vertebral backbone or backbone
-
what are the classes of vertebrae?
- -fish
- -amphibians
- -reptiles
- -mammals
- -birds
-
adaptation of fish?
- -streamline shape
- -scales for protection
- -gills for breathing
- -different colours for camouflage
- -lateral line for sensation
-
reptiles adaptation?
- -dry scaly skin
- -body divided into (head, neck, trunk, tail)
- -ear drums deep inside the head
- -short weak limbs to slide usually 4
- -cold blooded
-
types of fish with difference
- bony
- -small
- -mouth at front of the head
- -gill cover(opercullum)
- cartilaginous
- -large
- mouth on ventral surface
- gill slit (no opercullum)
-
mammals adaptations
- -fur/hair
- -mammary glands
- -external ear flaps
- -4 limbs
- -warm blooded
- -teeth
-
warm blooded meaning?
having internal mechanism that keeps constant internal temperatrure
-
birds adaptations
- -beaks according to food
- -feathers for lower density and insulation
- -tail to control direction
- -forelimb adapted into wings
- -waterproof oil to not absorb water
- -ear drum deep into the head
- -lay hard shelled eggs
-
amphibians adaptations
- -moist skin
- -4 limbs
- -external ear drums
- -nostrils on top of the head
- -males have dark area under the jaw (vocal sac)
- -protruded eye (to see under water)
- -lay egg in jelly coatr
- tadpoles
- -tail
- -external gills
- -stream line shape
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