B11.2(shorter) Flashcards
Why does the uterus lining build up every month?
To support a developing baby
Why does auxins cause plants to grow towards sunlight?
In a stem, the shaded side contains more auxin and grows longer, which causes the stem to grow towards the light. The plant does NOT bend towards the light. It grows because the auxin causes the cells to elongate on the shaded side, so this side grows more. This unequal growth of the two sides, results in the growth of the stem towards the light.
Why do hormones last for such a long time?
They have an effect until they are broken down
Why can insulin not be taken as a tablet?
Normal digestion would destroy it, making it ineffective
Which hormones are produced in the ovaries?
Oestrogen and progesterone
Which hormones are produced in the male and female reproductive organs?
Testosterone and oestrogen
Which gland is located at the base of the neck?
Thyroid
Where is glycogen stored?
Glycogen is stored in the liver.
Where are the adrenal glands located?
Above each kidney
What is type 2 diabetes?
Type 2 diabetes is a lifelong disease that keeps your body from using insulin the way it should. People with type 2 diabetes are said to have insulin resistance. This is not a genetic disorder.
What is type 1 diabetes?
Type 1 diabetes causes the level of glucose (sugar) in your blood to become too high. It happens when your body cannot produce enough of a hormone called insulin, which controls blood glucose. You need daily injections of insulin to keep your blood glucose levels under control.
What is the source of excess amino acids in the body?
Protein in diet
What is the role of the thyroid?
To control the metabolic rate of the body
What is the role of the pituitary gland?
Controls growth in children
Stimulates the thyroid gland to make thyroxine
Stimulates the testes to make sperm
Stimulates the ovaries to produce and release eggs
What is the role of the pancreas in the endocrine system?
To control the glucose levels in the blood
What is the role of the adrenal gland?
Produces adrenaline needed for the preparation of a flight or fight response
What is the name of the gas involved in fruit ripening?
Ethene
What is the endocrine system?
The endocrine system is a system which consists of glands and organs that make hormones and release them directly into the blood so they can travel to tissues and organs.
What is insulin?
Insulin is a hormone - produced by the pancreas - that regulates glucose concentrations in the blood.
What is gravitropism?
A growth in response to gravity
What is auxin?
A plant hormone which causes the elongation of cells in shoots and is involved in regulating plant growth
What is a hormone?
A hormone is a chemical substance, produced by a gland and carried in the bloodstream, which alters the activity of specific target organs.
What happens during puberty in males?
- Growth spurt
- Voice breaks
- Facial hair and underarm hair grows
- Testes grow and become active
What does the male hormone testosterone do?
Stimulates sperm production, muscle mass and fat distribution
What do auxins do in shoots?
Promote elongation of cells
What do auxins do in roots?
Prevent the elongation of cells
What are three uses of gibberellins in agriculture and horticulture?
Gibberellins end seed dormancy, encourages flowering and increases fruit size
What are three uses of auxins in agriculture and horticulture?
Auxins are commonly used in weedkillers, rooting powders and they promote growth in tissue culture.
What are spermicides?
Chemicals that disable or kill sperm
What are hormones and enzymes types of?
Proteins
What are features that appear during puberty called?
Secondary sex characterisitics
Types of tropisms
Positive phototropism
Negative phototropism
Positive gravitropism
Negative gravitropism
Treatment of type 1 diabetes
monitoring blood glucose levels and injecting human insulin throughout the day
Thyroxine negative feedback loop
if thyroxine levels rise,TSH levels fall so thyroxine returns to normal
if thyroxine levels fall, TSH levels rise so thyroxine falls to normal
Suggest why it is important that the dialysis fluid has the same concentration of dissolved substances as healthy blood
So that useful substances wont be lost from the person’s blood
Suggest one factor that might affect the amount of insulin injected by a patient
- How active the person is
Name the waste product of deamination
Urea
Name 2 substances present in dialysis fluid
- Urea
- Glucose
Male reproductive system
Key endocrine glands
Thyroid, pancreas, testes, ovaries and pituitary
Is glucagon released by the pancreas when the blood sugar is too high?
No, Glucagon causes glycogen to be converted to glucose, which increases blood sugar.
In which organ of the body are excess amino acids broken down?
Liver
How do intrauterine devices work?
The IUD releases copper into the womb, making it more difficult for the sperm to reach an egg
How can type 1 diabetes be treated apart from using injections of insulin?
Transplant a pancreas, this is difficult and risky
Female reproductive system
Explain two biological reasons why most doctors think that a kidney transplant is a better method of treatment than dialysis
- Dialysis requires a specific diet
- Dialysis can cause blood clots or infections
Explain how plant hormones can be used in weedkillers
The selective weedkiller contains a growth hormone that causes the weeds to grow too quickly and die. Because most weeds have broader leaves than grass or wheat, the weedkiller is absorbed in larger quantities by the weeds.
Effects of the adrenal gland on the body
- increases heart and breathing rate
- increases mental awareness
- boosts delivery of oxygen and glucose to brain/muscles
Disadvantages of fertility treatments
- Emotional stress
- Risk of multiple pregnancies
Differences in nervous and hormonal control
nervous. Hormonal
electrical impulse. chemical
muscles or gland. targetorgan
muscle contract. chem change
rapid. slower
short long
Differences between type 1 and type 2 diabetes
Type 1 - cells dont produce enough insulin
Type 2 - cells no longer respond to insulin
Dangers of high blood glucose levels
- blurry vision
- frequent urination
- fatigue
Advantages of fertility treatments
Offer hope to couples who are unable to conceive naturally
3 similarities in puberty for boys/girls
- Pubic hair growth
- External genitalia growth
- Underarm hair growth
