B4,B5 Flashcards
What are parts of the blood?
- Plasma (white blood cells ,red) (platelets)
What is plasma?
Liquid part of the blood and transports solluble digestion products (glucose) from small intestine to other organs and carbon dioxide from organs to lungs to be breathed out and urea from liver to kidneys
What are red blood cells?
Transports oxygen from lungs to body cells
Adaptation of red blood cells?
- Contains haemoglobin
- No nucleus (more room for haemoglobin)
- Bioconcave disc
Haemoglobin + oxygen = oxyhaemoglobin
oxyhaemoglobin
Wh do red blood cells have a bioconcave disc?
Oxygen difuses in and out rapidly
What are white blood cells used for?
Making antibodies
Key things about white blood cells?
- contains nucleus
- Carrys DNA which encodes the instructions white blood cells need to do
What are platelets?
- Tiny fragments of cells and help blood clot
What is donated blood used for?
- Replace blood lost during injury
- Some people are also given platelets to help in clotting
- Proteins can be used for antibodies
Problems with donated blood?
- Have to be same blood type or will reject blood and patient could die
- Lots of diseases can be transmitted via blood (but in the UK it is screened for infections)
What are cardiovascular diseases?
Diseases of heart and blood vessels
(Non communicable)
What happens in a coronary heart disease ?
Layers of fatty materials build up inside the coronary heart disease. Then causes them to narrow. This then reduces blood flow and a lack of oxygen. Can result to heart attacks
What are the treatements for coronary heart diseases?
- Statins which lower the cholestrol in the blood. This slows down the rate fatty materials build up
Advantages of statins?
- Reduce the risk of heart disease
Disadvantages of statins?
Unwanted side effects eg liver problems
When can people be treated using a stent?
When their coronary artery is totally blocked
What is a stent?
A tube which can be inserted into the coronary artery to keep it open
Advantage of a stent?
Blood can flow normally through the artery
What happens when heart valves don’t fully open?
Pump extra blood through the blood and can cause heart to enlarge
What can leaky valves cause?
Someone weak and tired
When heart valves are faulty what can you do?
Replace with mechanical wave or a valve from an animal such as a pig
Advantages amd disadvantages of valves?
Mechanical valves can last a lifetime but increase bloodclots
Animal valves do not last long but patients don’t nees to take drugs
What happens when people have a heart which cannot pump enough blood?
- Given a donated heart or lungs
- Artificial heart
Problems with donating heart?
- Not enough donated hearts to treat every patient
- must take drugs to stop donsted heart being rejected from immune system
What’s disadvantage of an artificial heart?
Increases blood clotting not a good long term
What happens after air is inhaled?
1) Air passes in lungs through a tube called trachea
2) Rings of cartilage prevent trachea collapsing
3) Trachea splits into two smaller tubes called bronchi
4) Bronchi further divides into tubes called bronchioles
5) Bronchioles end in tiny sacs called alveoli
What’s alveoli?
Gases difuse in and out of blood stream
How is alveoli adapted?
- Lungs have huge surface area
- Thin walls so diffusion path is slow
- Good blood supply
What does breathing increase?
Rate of diffusion
What does breathing bring in?
Fresh oxygen and takes away carbon dioxide . Concentration gradient is high
What do changes is genes lead to?
Uncontrolled growth and mitosis (tumor)
What are the two type of tumors?
- Benign
- Malignant
What are benign tumours?
Growth of abnormal cells in one area and contained within a membrane
A key feature of benign tumours?
Do not invade other parts of the body (stay in one place)
Whats a malignant cell?
Invade neighbouring tissues and move into the bloodstream
What cells are classed as cancer?
Malignant tumour
What are secondary tumours?
The malignant cells spread to other parts of the body
What cancers are normally caused from genetics?
- Breast cancer
- Prostate cancer
- Large intestine
Name all cancers linked to each other?
Lung cancer = smoking
Skin cancer = ultraviolet
mouth and throat cancer = alcahol
What is radon?
Radioactive gas and Increases risk to lung cancer as it damages DNA in our cells
What’s a comminicable disease?
It can be spread from person to person (measles) and are spread by pathogens such as bacteria or viruses
What’s a non-communicable disease?
Cannont be spread from person to person eg heart disease
What is health?
State of physical and mental well being
What causes bad health?
- poor diet
- Stress
- life situations (working with chemicals)
What can HPV cause?
Cervical cancer
How is cervical cancer caused?
Hpv infects cells of cervix
What happens when a disease can be triggered by the immune system?
Body is infected with a pathogen but person is left with an allergy
What is studying the patterns of disease to determine the risk factor called?
Epidemiology
What’s a causal mechanism?
Is there any scientific explanation why it could happen
What’s a carcinogen?
They discovered cigarette smoke contains chemicals which damage DNA and increase cancer
How do you avoid biasm?
Take a bigger range of answers from different cities
Name some non commuicable diseases?
- Cardiovascular disease
- Type 2 diabetes
- Lung cancer
What increases the risk of coronary heart diseases?
- Diet in high fat and low vegetables increases the levels of cholestrol in the blood. Also increases fatty materials in arteries
- Diet high in salt increases blood pressure
- Smoking
Excercise reduces these
Risk factors for smoking?
- Chemicals which trigger off cancer
- lead to a Poor quality life
- Increases miscarriage and baby with low body mass
- Drinking can cause fetal alcahol syndrome (learning difficulties)
Effects of drinking alcahol?
- Increase liver cancer and cirrhosis
- Addiction and memory loss
What can type 2 diabetes lead to?
- Blindness or amputation of limb
- Obesity
Whats the epidermal cells?
The cells on the leaf and forms epidermis tissues. Also protects surface of leaf
Adaptations of epidermis?
Transparent to allow light pass through photosynthetic cells
What is the waxy cuticle?
The layer the upper epidermis is covered by
What does the waxy cuticle do?
Reduces evaporation of water from surface of leaf. Helps prevent dry out
Where is the stomata located?
On the lower epidermis
What is stomata?
- Allows carbon dioxide to enter leaf and oxygen to leave
- Controls water vapour that can pass out of leaf
Where do you find palisade mesophyll?
Top of the leaf
What are palaside cells full of?
Chloroplasts
What’s the spingy mesophyll?
- Full of air spaces and allow carbon dioxide to diffuse from stomata through spongy mesophyll to palisade cells
How does oxygen diffuse in leaves?
Oxygen also diffuses from palaside cells through spongy mesophyll to stomata
What does xylem tissue do?
Transports water from roots to stem and leaves. Also used in photosynthesis
What does xylem transport?
Dissolved mineral ions. Magnesium to make chlorophyll
What does phloem tissue do?
Transports dissolved sugars produced by photosynthesis from leaves to rest of the plant. Can be used immedietly or for starch
What’s translocation?
Movement of sugars and other molecules through phloem
Where do you find meristem tissues?
Growinb tips
What’s the palaside mesophyll?
Photosynthesis takes place
What does xylem tissue do?
Transport water and mineral ions from roots to leave
How does water enter roots?
Root hair cells
Whats transpiration?
When water is constantly evaporating from surface of the leaves
Describe the transpiration stream?
1) Starts with evaporation of water from cells inside leaf
2) water diffuses through air spaces in spongy mesophyll and out of stomata
3) Water pases from xylem to leaf to replace water lost
4) Water is finally drawn into the root hair cells of the leaf
What does transpiration stream transport?
Disolved mineral ions such as magnesium
When is rate of transpiration greater?
- Higher temperatures (evaporation is faster when temp is higher)
- when it is dry
- Windy conditions
- Light intensity increases
What is stomata surrounded by?
2 guard cells
What happens when light intensity is high?
Guard cells swell and change shape. Opens stomata to open and co2 diffuses. When it is hot it closes shape so water doesn’t lose through transpiration. Means it cannot photosynthesise
