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Flashcards in Control Systems Deck (59):

What pair of chromosomes does a woman have?



Name the four hormones involved in the menstural cycle



Describe the menstural cycle

FSH causes follicle to mature in the ovaries and stimulates oestrogen production. Oestrogen then causes the uterus lining to thicken and grow, this also causes a spike in LH hormone. LH starts ovulation makes the follicle develop into a corpus liteum which secrets progesterone. Progesterone keeps the uterus lining thick and invites the grow of LH or FSH . When progesterone falls the uterus lining beaks down


How is glucose removed from the nephron

Removed from the nephron from the re-absorption this using energy and occurs by active transport


Urea enters the nephron from the

Bow mans capsule


Which hormone controls the permeability of the collection duct?



Urine is transported from the bladder through the



Which hormone stimulates the release of the egg?

LH luteinizing hormone


What is a daily rhythm in a mall called?

Circadian rhythm


What are monoclonal antibodies

Identical copies of antibodies made in laboratories


How are monoclonal antibodies made?

A mouse is vaccinated to start the production of monoclonal antibodies, spleen cells from the mouse are collected. These are fused with myeloma cells (cancer) this forms a hybridoma. This cell rapidly divides the antibodies are then separated form the cells.


What is photoperiodism and why is it helpful

Plants can sense when the days get longer and therefore know when to germinate, some plants grow all year but grow faster in Autumn. Some plants sense short days or long nights and stop growing to brace for winter.


How do young lupin leaves protect themselves.?

They produce poisonous chemicals called alkaloids.


Are plant poisons useful and why

Digoxin found in foxgloves in small doses can improve the heartbeat
Quinine produced in cinchona trees can treat malaria


What does LH do in the menstural cycle

Stimulates ovulation at day 14 causing the follicle to rupture releasing the egg. It stimulates the remains of the follicle to develop to a corpus luteum which secrets progesterone


What does FSH do

Causes a follicle to mature in on of the ovaries and stimulates oestrogen production


What does oestrogen do

It stimulates the uterus linning do grow and causes a surge in LH


What does progesterone do

It maintains the lining of the uterus. It inhibits the production of FSH and LH. When progesterone level falls and there is a low oestrogen level the uterus lining breaks down.


What are types of fertility treatment

Surrogate mother


Describe why a woman may use hormones

Some women have levels of FSH which is too low and can't cause the eggs to mature . The hormone LH and FSH can be injected to stimulate egg release


What are the pros and cons of hormone treatment for pregnancy

Pros, it helps a lot of women get pregnant
Cons, it doesn't always work some women may do it too many times which can be expensive, it can result in the stimulation of multiple eggs leading to triplets etc


Describe the process of IVf

In vitro fertilisation involves collecting eggs from a woman's ovaries and fertilising them in a lab. This is grown into an embryo then inserted back into a woman


What are pros and cons with IVF

Pros, allows an infertile couple to have a child
Cons, some women have strong reaction to the hormones which stimulate egg production. There have been reports of increased risk of cancer . Multiple births can happen if more than one embryo becomes a baby


Why is IvF great

Women who can't produce eggs can use an egg donors eggs and have IVF to conceive


What is a surrogate mother

Someone who carries your child because you can't


How is the baby from a surrogate mother sometimes made

Through IVF a sperm or egg from the couple is used to create the embryo


How many pairs of chromosomes are there

22 matched pairs and one additional pair which determines sex


What happens to the sex chromosomes when making sperm

They are drawn apart in the first meiosis division , the sperm has a 50% chance of X chromosome and 50% chance of Y


What does it mean by sex linked genetic disorder

If the allele is located on a sex chromosome


Why do men not have the same alleles as women

The Y chromosome is much smaller so most of the genes are carried on the X


What is colour blindness

A faulty allele carried on the X chromosome


Why is colour blindness rarer in women

Women have two X chromomes , colour blindness is recessive this means they need to recessive alleles of the disorder colour blindness to be affected, as men only have one X chromosome and the allele is on the X chromomes if they have the recessive allele they have colour blindness


What does a number of bacteria of time graph look like

Exponential curve, as the number of bacteria double every 20 min


How did Louis Pasteur prove bacteria caused disease

He used two flasks, one straight top and one curved. He placed broth in each. As the curved flask had a curve the bacteria settled in it not affecting the broth, in the straight neck the bacteria fell into the broth and cause decay


How can you test for microbacteria

Using resazurin dye


How does Reszurin dye work

It's colour changes depending on oxygen levels, microorganism use oxygen when they respire the dye will change to red when the oxygen in used , finally colourless


What do B lymphocytes do in response to infection

They produce antibodies


What do antibodies do

They kill pathogens by binding to its antigen


What's a problem with b lymphocytes

They are highly specific there antibodies can only kill one type of pathogen


Why is immune response slow to a new pathogen

There aren't many B lymphocytes that can produce antibodies at the tame


What is a memory lymphocyte

They are b lymphocytes hat remain in the body for a long time and remember a specific antibody, they can respond quickly to a known infection and kill it before symptoms are shown


What is immunisation

It involves injecting dead or inactive microorganism s into the body. They carry antigens this causes the body to produce antigens and Respond. This causes the production of memory lymphocytes which can respond quickly to a real infection


What did Edward Jenner do

Used cowpox to immunise against small pox


What are the pros and cons of infection

Large outbrakes of disease can be prevented if a large percentage of the population are immunised. Some diseases can be eradicated. However it doesn't always work and sometimes you can't have a bad reaction to vaccines


What are monoclonal antibodies

B LYMPHOCYTES FUSED WITH CANCER CELLS, this means they can divide


What's a problem with b lymphocytes

They don't divide very easily


What is a hybridoma

It is a fused b lymphocyte cell and a tumour they divide quickly and produce identical antibodies


What do monoclonal antibodies do in pregnancy tests

Antibodies bind to a hormone find in women's urine en they are pregnant . The urine moves up the strip to the blue beeds, the beads and the hormone bind to the antibodies on the strip, is causes a colour change as the blue beads stay on the strip. If the hormone wasn't present the urine would carry the beads off the strip meaning no colour change


How are monoclonal antibodies used to diagnose cancer

Different cells in the body have different antigens on the surface. Cancer cells have antigens that aren't found on normal body cells, monoclonal antibodies bind to these tumour markers


How can you detect the monoclonal antibodies in the body

They are labelled with a radioactive elements . The monoclonal antibodies are given to a patient through a drip when the find the cancer they bind with it. A detector detects where the radioactive element is this will be where the cancer cell is


How can antibodies be used to treat cancer

An anti cancer drug is attached to the monoclonal antibodies. It is given through a drip the antibodies bind with the cancer cells because of there antigens, the drug kills the cancer cells. This is better than radiotherapy which can kill normal body cells


How can monoclonal antibodies find blood clots

When blood clots proteins in the blood join together. Monoclonal antibodies have been developed to bind to these proteins attach a radioactive element and detect


Give examples of drugs from plants

Aspirin - bark of the willow tree
Taxol - bark of the Pacific yew tree
Quinine - cinchona tree


What is aspirin

It comes from the bark of a willow tree and can treat pain and lower fever


What is taxol

It comes from the bark of the Pacific yew tree , this drugs can be used to fight cancer


What is quinine

It used as a treatment against malaria and comes from the South American cinchona tree


What can affect crop yields



What ways to pests reduce crop yeild

Fruit flies feed on them. Weeds that grow near plants compete for nutrients so if the plant gets less nutrients its yeild will be less as its growth is worse. Pathogen takes energy as the plant has to replace bits, this means less energy for useful things like apples


Why are pests a problem

They have to be dealt with which is expensive to do. You need to by pesticides or disease resistant crops