B2- Disease and plant organisation

Topic 2b

What is coronary heart disease?

When layers of fatty material build up in arteries, restricting blood flow can cause heart attack

What is the role and an adaptation of the upper epidermis?

Transparent and thin to allow light to pass through

What is the role and an adaptation of Palisade mesophyll?

Conatins lots of chloroplasts for photosynthesis near the top of the leaf and absorbs more sunlight

What is the role and an adaptation spongy mesophyll?

Contains big air spaces to allow gases to exchange/diffuse

What is the role and an adaptation of lower epidermis?

Has small holes called stomata controled by guard cells allowing co2 to diffuse out

What do xylem and phloem form and do?

They form vascular bundles that deliver water/nutrients to the leaf and support the structure

How do tumours form?

Abnormal cells form causing uncontrollable cell division

What are the 2 types of tumour?

Benign and malignant

What type of tumour isn’t cancerous?

Benign

Do benign tumours spread around body?

It stays in one place and normally isnt dangerous

Are malignant tumours cancerous?

Yes they are cancers!They grow and spread to healthy tissues

How is a secondary tumour formed?

Malignant cells break off and spead into the bloodstream

What are some risk factors that cause cancer?

Smoking (lung mouth cancer)

Obesity (bowel lung kidney cancer)

UV exposure (skin cancer)

Faulty genes (ovarian and breast cancer)

What tumour is cancerous?

Malignant

What are stents?

A tube inserted into arteires, pushing the wall out squashing fatty depostis (cholestrol)

Name 2 advantages of stents

• Effective for a long time

• Recovery time is quick

Name 2 disadvantages of stents

• Risk of complications during surgery/ infections

• Risk of blood clot developing near stent

What is a statin?

A drug that reduces the amount of LDL cholestrol, slowing down formation of fatty depostis

What is cholestrol?

A lipid that your body produces to function properly

Name an advantage of statins

Can increase HDL cholestrol (good) and remove LDC (bad) cholestrol

Name 1 disadvantage of statins

The effect isnt instant and can take time to kick in

What is health?

A state of mental and physical wellbeing

What is a communicable disease?

Speads from person to person (contagious) eg. bacteria, viruses and parasites

What is a non-communicable disease?

Can’t spread between people eg. asthma, cancer and coronary heart disease

What is translocation?

Transport of dissolved sugars through the phloem

What is transpiration stream (3)

Water evaporstes and diffuses through stomata

Water is drawn up from xylem to rest of plant

In turn water is drawn up from roots resultinf in transpiration stream

What does xylem transfer?

Water and mineral ions

Where are substances transpotted to and from in xylem

roots-stem and leaf

Where are substances transpotted to and from in phloem

leaves-rest of plant

What is the structure of phloem

Made up of elongated living cells

What substances are transported in phloem

Food substances (mainly dissolved sugars)

What is the structue of xylem

Dead cells joined together, no end walls (strengthened with lignin)