Biology Paper 1 Flashcards
What 4 components make up the blood and what do they do?
-red blood cells: carry oxygen
-white blood cells: fight pathogens
-platelets: help the blood to clot
-plasma(the only liquid part in the blood): transports nutrients, urea and hormones.
Where does the artery transport blood?
Away from the heart.
Where do veins transport blood?
Into the heart.
What do capillaries do?
They transport blood and substances to the tissues of the body, and remove waste from surrounding cells.
Which path does deoxygenated blood from the body take through the heart?
It enters through the vena cava into the right atrium. Then it flows into the right ventricle and exits the heart to the lungs via the pulmonary artery.
Which path does oxygenated blood from the lungs take through the heart?
It enters through the pulmonary vein into the left atrium. It then travels into the left ventricle and then out, to the body, via the Aorta.
The heart is made out of ________ muscle.
Cardiac.
The heart is a double _____ .
Pump
What is the structure of an artery?
-thick outer wall to push blood at extremely high pressures.
-small lumen
-thick muscular layer
What is the structure of a capillary?
-one cell thick walls for a short diffusion pathway making it more efficient.
What is the structure of a vein?
-larger lumen
-valves to prevent the backflow of blood
-thinner outer layer
What is CHD?
Coronary heart disease - when the blood vessels that supply blood to the heart are blocked.
What treatments can help the build up of fatty acids inside the coronary arteries?
Statins (drugs that lower harmful cholesterol)
Stents (metal cylinder grids inserted into the artery to keep it open)
Where would you place an artificial pacemaker?
On the wall of the right atrium.
What are the risk factors for CHD?
-smoking
-high blood pressure
-diet high in cholesterol
-not enough excersise
What happens if valves dont open or close fully?
Don’t close efficiently: blood can leak
Don’t open efficiently: blood cannot pass through, clots or high pressure.
What are the symptoms of faulty heart valves?
-shortness of breath
-swelling in the ankles
-feeling unusually tired
What can faulty valves be replaced by?
-mechanical valves:cheaper, lasts 20-30 years, made from titanium, high risk of a blood clot, daily blood thinning tablets, increased risk of stoke or heart failure.
-biological valves: more expensive, lasts 10-20 years, made from animal tissue, low risk of blood clot, maybe unethical, no long term medication needed.
What is the definition of breathing?
Breathing is the mechanical process which gets air in and out of the lungs.
What adaptations do alveoli have?
Large surface area
Moist surface
Short diffusion pathway
Thin walls
Good blood supply
Dense capillary network
What is diffusion?
The movement of particles from a higher concentration to a lower concentration.
What is osmosis?
The movement of water particles from higher water potential to lower water potential across a partially permeable membrane.
What is active transport?
The movement of particles from a lower concentration to a higher concentration (against the concentration gradient) requiring energy.
What is the reproductive organ in the plant?
Flower
The flower attracts insects and facilitates pollination.
What is the primary function of the stem in a plant?
Transports sugars, water, and minerals
The stem also supports the leaves.
What role do leaves play in a plant?
Absorbs light for photosynthesis
Leaves are crucial for converting light energy into chemical energy.
What is the function of roots in a plant?
Absorb water and minerals from the soil
Roots also anchor the plant to the ground.
What are the two main types of vascular tissue in a plant stem?
Xylem and phloem
What type of cells make up xylem?
Dead cells joined end to end
What does xylem transport?
Water and mineral ions
In which direction does water move in xylem?
Upwards
What process is xylem involved in?
Transpiration
What type of cells make up phloem?
Living cells with pores in the end walls
What does phloem transport?
Glucose
In which directions can glucose move in phloem?
Both directions
What process is phloem involved in?
Translocation
What is the primary function of root hair cells?
To uptake water and minerals from the soil
What feature of root hair cells increases absorption?
Large surface area
What do root hair cells contain to store water?
Large vacuole
What organelle is abundant in root hair cells to aid in active transport?
Mitochondria
Fill in the blank: Xylem is involved in _______ and transports water and minerals.
Transpiration
Fill in the blank: Phloem is involved in _______ and transports glucose.
Translocation
What is the spongy mesophyll?
It increases the rate of diffusion of gases as it is a layer of cells containing air spaces.
What is the waxy cuticle?
It is the waxy layer on top of the leaf which prevents evaporation.
What is the upper epidermis?
The transparent layer at the top of the leaf which allows for efficient gas exchanged and the passing through of light.
What is the palisade mesophyll?
It is near the top of the plant and contains lots of chloroplasts, photosynthesis occurs in the chloroplasts.
What is the lower epidermis?
The transparent layer at the bottom of the leaf which allows for efficient gas exchange.
What are the guard cells?
The cells on either side of the stomata which controls whether it is open or closed.
What is transpiration?
Transpiration is the evaporation of water from the surface of the leaf through the stomata.
What is the transpiration stream?
The flow of water through a plant.
Which factors affect the rate of transpiration?
-increased temperature=increased transpiration
-increased wind=increased transpiration
-increased light intensity=increased transpiration
-increased humidity=decreased transpiration
What does a potometer show?
The uptake of water.
What is the formula for photosynthesis?
Carbon dioxide + water -> glucose + oxygen
Is the reaction of photosynthesis exo or endothermic?
Endothermic
What is glucose used for in a plant?
-converted into insoluble starch for storage
-used for respiration
-used to produce cellulose
-used to produce amino acids for protein synthesis
-used to produce fat or oil for storage
What is the definition of health?
Health is a state of physical and mental well-being.
What is a communicable disease?
A disease that can be transmitted
What is a non-communicable disease?
A disease that cannot be transmitted.
What is a pathogen?
A pathogen is a microorganism that causes disease.
What are the 4 types of pathogen?
-bacteria
-virus
-protist
-fungi
How do bacteria’s make us feel unwell?
They release toxins into our bodies.
What can be prescribed to treat bacterial infections?
Antibiotics
What is the virus life cycle?
-the virus invades
-the virus replicates
-the virus bursts the cell and spreads
How are pathogens transmitted?
-airborne:inhaling droplets in air
-direct contact:touching something they touched
-waterborne:drinking dirty water
-animal borne: mosquitoes
-mother to baby
-blood born: sharing needles
-foodborne: raw chicken
Which diseases are spread through the air?
Covid-19, common cold
Which diseases are spread through direct/sexual contact?
Chlamydia, gonorrhoea, HIV
What disease is spread through water?
Cholera
Which diseases are spread through animals?
Malaria and rabies
Which disease are foodborne?
Salmonella
Which diseases are congenital (mother to baby)?
HIV
Which diseases are bloodborne?
HIV and hepatitis b & c
Which examples of good hygiene can reduce the spread of communicable diseases?
-washing hands
-sanitising surfaces
-coughing into a tissue
-preparing food correctly
Salmonella
Transmitted: through undercooked food
Symptoms: fever, cramps, diarrhoea, sickness
There is no treatment
Prevent the spread: poultry are vaccinated
Gonorrhoea
Transmitted: unprotected sex
Symptoms: thick yellow or green discharge, painful urination
Treated by antibiotics
Prevent the spread: by wearing protection and reducing the number of sexual partners
Measles
Transmitted: through inhalation of droplets from coughs or sneexes
Symptoms: fever, red skin rash
Treatment: no treatment
Prevent the spread: isolating, vaccination
HIV
Transmitted: direct sexual contact or exchange of bodily fluids
Symptoms: mild, flu like illness
Treatment: anti-retroviral drugs to slow it down
Prevent the spread: using condoms, not sharing needles
TMV (tobacco mosaic virus)
Transmitted: contact between diseased plants
Symptoms: mosaic patterned discolouring on leaves
Treatment: no real treatment
Prevent the spread: removing and destroying the infected plants
Rose black spot
Transmitted: by wind or water
Symptoms: purple or black spots on leaves, leaves turn yellow and drop, reduced photosynthesis
Treatment: fungicides
Prevent the spread: removing and destroying infected leaves and plants
Malaria
Transmitted: bitten by infected mosquitoes
Symptoms: recurrent fever, headache, vomiting, diarrhoea and can be fatal.
Treatment: antimalarial medication
Prevent the spread: insecticide to kill mosquitoes, repellants and nets
Athletes foot
Transmitted: in humid conditions such as damp, wet socks
Symptoms: itchy, white patches between toes.
Treatment: hygiene, anti fungal medication or cream
Prevent the spread: dry feet thoroughly, don’t share dirty socks
What is the life cycle of malaria?
-Infected mosquitoes bites human
-malaria infects liver and reproduces asexually
-malaria parasite now in blood
-a different mosquito bites infected human and therefore becomes infected
Which diseases are caused by viruses?
TMV
HIV
Measles
Which diseases are caused by bacteria?
Gonorrhoea
Salmonella
Which diseases are caused by protists?
Malaria
Which diseases are caused by fungi?
Athletes foot
Rose black spot
What is the first barrier of defence?
The skin, tears, mucus and saliva.
Are the second and first barriers specific or non specific?
Non-specific.
What is the second barrier of defence?
Phagocytosis ( the engulfing of pathogens by a white blood cell)
What is the third barrier of defence?
Antibodies and antigens.
Is the third line of defence specific or non-specific?
Specific.
How do white blood cells destroy pathogens?
-WBC produce antibodies
-antibodies attach to antigens on surface of pathogen.
-antibodies target and destroy specific pathogens.
-made of proteins so their shapes are complimentary.
Where are antigens?
On the surface of pathogens
What is a vaccine?
Small quantities of a dead or inactive pathogen deliberately injected into the bloodstream.
What is mitosis?
Mitosis is asexual division for grown and repair. It has one division for 2 genetically identical daughter cells with 46 chromosomes each.
What is meiosis?
Meiosis is sexual division for gametes (sex cells). It has 2 divisions for 4 genetically different cells with 23 chromosomes each.
What is stage 1 in the cell cycle?
Interphase.
What is stage 2 in the cell cycle?
Mitosis.
What is stage 3 of the cell cycle?
Cytokinesis.
Is bacteria prokaryotic or eukaryotic?
Prokaryotic.
What do the ribosomes do in a cell?
The site of protein synthesis.
