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Flashcards in Control Systems Deck (29)
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1
Q

What does cell metabolism lead to

A

build-up of waste products in the blood, including carbon dioxide and urea

2
Q

How is urea produced and removed

A

produced from the breakdown of excess amino acids in the liver and is removed by the kidneys

3
Q

Describe the structure of the urinary system

A

a) renal artery and vein - vein = carry cleaned blood back to the body, arteries = carry blood from the body to the kidneys
b) kidneys - remove substances including urea from the blood and make urine
c) ureters - carry urine from the kidneys to the bladder
d) bladder - stores urine
e) urethra - urine flows through the urethra to the outside of the body

4
Q

Describe possible treatments for kidney failure

A

kidney dialysis - blood is passed through a dialysis machine to remove waste urea and excess substances before the blood is returned to the body.
organ donation - a healthy kidney from another person is placed in the body and connected to the blood system, so that waste substances are removed from the blood

5
Q

Describe the structure of a nephron

A

a) glomerulus and Bowman’s capsule - glomerulus = small knot of capillaries, bowman’s capsule = cup shape. filtration of small molecules from blood into tubule, including water, glucose,salts and urea
b) convoluted tubules -
c) loop of Henlé
d) collecting duct

6
Q

Explain how the structure of the nephron is related to its function in filtering the blood and forming urine (osmoregulation),

A

the blood in the glomerulus is under high pressure. the walls of the glomerulus and bowman’s capsule are leaky so small molecules filter from the blood into the capsule. the large surface area of the glomerulus and capsule means filtration happens as quickly as possible. the convoluted tubule and loop of henle lie close to a capillary, so that glucose and water can be reabsorbed into the blood from the tubule

7
Q

describe the role of ADH (produced by the pituitary gland) in regulating the water content of the blood

A

to control the amount of water reabsorbed from the nephrons. this regulates the water content of the blood

8
Q

describe how ADH production is controlled by a negative feedback mechanism

A

an increase in blood water content causes the pituitary gland to be reabsorbed by the collecting duct in the kidneys so more water is excreted by the kidneys. a decrease in blood water content causes the pituitary gland to secrete more ADH, which causes less water to be excreted by the kidneys. this is a negative feedback mechanism because a change in blood water content causes can opposite change that restores the normal blood water content

9
Q

what is the menstrual cycle controlled by

A

menstrual cycle is controlled by the hormones

oestrogen and progesterone

10
Q

Describe the stages of the menstrual cycle

A

1) mensuration is the breakdown of the uterus lining. it begins on day 1 of the cycle and usually lasts between 4 and 7 days.
2) during the second week, the lining of the uterus is gradually built up
3) ovulation is the release of an egg from an ovary. this usually takes place around day 14.
4) days 14-16 are the days when fertilisation is most likely to take place
5) the lining of uterus continues to build up throughout weeks 3 and 4
6) if fertilisation occurs then the uterus lining is maintained and mensuration does not happen

11
Q

Explain why the uterus lining is maintained if fertilisation occurs

A

the embryo that develops form a fertilised egg needs to embed in the thick uterus lining, so that it can get nutrients from the mother

12
Q

Describe how oestrogen, progesterone, FSH and LH control the menstrual cycle

A

s

13
Q

describe how the menstrual cycle is controlled by a negative feedback mechanism

A

changes caused by the release of of hormone inhibit the secretion of other hormones. for example, progesterone inhibits FSH and LH

14
Q

Explain how the structure of an egg is adapted to its function

A

> cytoplasm to provide nutrients that the embryo will use to grow and develop
haploid nucleus contains one set of genetic material
cell membrane changes immediately after fertilisation to block entry of other sperm

15
Q

Explain how the structure of a sperm cell is adapted to its

function

A

> acrosome containing enzymes to digest into the egg
haploid nucleus contains one set of genetic material
middle section containing mitochondria that release energy from respiration to power tail
tail for movement

16
Q

describe the advantages and disadvantages of infertility treatments

A

Egg donation:
A) used when woman of the couple has no eggs in her ovaries
D) hormones used to collect eggs may cause a bad reaction. the egg donor may want access to the child.
IVF:
A) useful if a man produces only a few healthy sperm
D) babies may be born early, which can cause problems at birth or later in life
Surrogate mother:
A) used when the woman of the couple cannot grow an embryo in her uterus
D) some surrogate mothers find it hard to hand over the baby to the couple
Hormones:
A) used when the woman’s hormones are not enough to cause ovulation
D) there is a greater risk of having several babies at the same time. these babies tend to be born earlier than normal, which can cause problems at birth or later in life

17
Q

how is the sex of a person is controlled

A

the sex of a person is controlled by one pair of

chromosomes, XX in a female and XY in a male

18
Q

Describe Edward Jenner’s contribution to the development of vaccines

A

Edward Jenner gave a boy a pathogen that causes a mild disease called cowpox. the boy developed cowpox and recovered,. later Jenner gave the boy the pathogen that causes a dangerous disease called small pox. the boy did not develop small pox - the cowpox vaccine had made him immune to smallpox

19
Q

Explain the process of immunisation

A

1) a vaccine containing a dead or weakened pathogens injected into the body. it has antigens on its surface.
2) a type of white blood cell, called a lymphocyte, with an antibody that perfectly fits the antigen is activated
3) this lymphocyte divides over and over again to produce clones of identical lymphocytes
4) some of the lymphocytes secrete large amounts of antibodies. the antibodies stick to the antigens and destroy the pathogen

20
Q

describe the advantages and risks associated with immunisation

A

risks:
> some people get a mild reaction of swelling or soreness, or a mild form of the disease
> very rarely a person has a major harmful reaction
advantage:
> immunity is produced without being ill
> immunity lasts a long time, often for life
> if most people are immune, then the few unvaccinated people are also likely to catch the disease

21
Q

Describe the role of memory lymphocytes in secondary

responses to antigen

A

memory lymphocytes are ready to respond immediately if the same antigen ever turns up again.

22
Q

explain how sex linked genetic disorders are inherited

A

s

23
Q

Describe the production of monoclonal antibodies, and the use of them

A

s

24
Q

Describe how the exponential growth of a population of bacteria can lead to rapid development of an infection

A

S

25
Q

describe Louis Pasteur’s contribution to the development of aseptic techniques

A

Carried out experiments showing that once microorganisms are destroyed, they do. To suddenly appear again. Microorganisms can only be transferred from something that already contains them, such as the air. Led to the development of aseptic techniques that are us to destroy microorganisms. These techniques are used to prevent spoilage of food and in surgery to prevent infection of wounds.

26
Q

how do plants defend themselves against attack from pests and pathogens, how can we use them to can be used to treat human diseases, disorders or relieve symptoms

A

> poison in their cells to deter pests that try to eat them
chemicals that kill pathogens! which infect them and cause disease
humans can use them to: treat human disease, disorders, and relieve symptoms

27
Q

explain impact that attack by pests and pathogens on plants has on human food supply

A

Most of the food we eat comes from plants. Pathogens and pests that attack crop plants cause damage. This reduces the yield of the crop.

28
Q

Explain photoperiodic and it’s importance in plants

A

The response of a plant that changes as day length changes. Most noticeable where day length changes throughout the year.
> growth - plants stop growing over winter. some trees lose their leaves
> germination - some seeds germinate better in spring when day length is getting longer. This is usually when conditions for growth are getting better.
> reproduction - some produce flowers in response to days getting longer. Other plants flower when day length gets shorter.

29
Q

explain circadian rhythms in living organisms

A

Is a pattern of bah our that changes over a 24 hour period. Controlled by a biological clock. External factors such as day and night help to match the clock to changes in environment.