Topic One - New Technology

Question 0

How is DNA arranged?

Answer 0

DNA is arranged in strands called chromosomes which contain genes that code for specific characteristics

Question 1

Where can DNA be found?

Answer 1

DNA is present in nearly all cells at all times and can be found in the nucleus

Question 2

Describe chromosomes

Answer 2

Chromosomes are long strands of DNA which can be found in pairs

Question 3

Describe the shape of a DNA molecule

Answer 3

Two strands paired up to form a ladder, twisted round, creating a double helix shape

Question 4

What is DNA made up of?

Answer 4

DNA is made up of four units named A, C, T and G. The bases on one strand pair up with the bases of the second strand

Question 5

What does the order (or the sequence) of bases on each strand do?

Answer 5

It makes a code which determines the characteristics of different species and different organisms within the same species

Question 6

Who were the scientists who helped produce a model of the structure of DNA?

Answer 6

Franklin & Wilkins used X-rays to try and work it out, and with their findings, another duo called Watson & Crick discovered the double helix structure of DNA

Question 7

What are chromosomes made up of?

Answer 7

Genes, all lined against each other. Both genes and chromosomes make up the chemical DNA

Question 8

How many chromosomes do humans have?

Answer 8

Humans are made up of two sets of 23, with one set coming from each parent (making 46 in total)

Question 9

What causes variation in inherited characteristics?

Answer 9

Alleles

Question 10

How many copies of each chromosome do animal and plant cells have and what does that mean?

Answer 10

They contain two copies of each chromosome (one from male, other from female), meaning every cell contains two copies of each gene

Question 11

What do genetic crosses do?

Answer 11

Genetic crosses are used to predict the chances of offspring inheriting various types of characteristics from their parents

Question 12

What are inherited diseases/conditions caused by?

Answer 12

The presence of certain alleles passed from parent to offspring

Question 13

Is it ever possible to have an allele for genetic disorder, yet not have the actual condition?

Answer 13

Yes, if the condition is caused by a recessive allele. You’d need two of these to actually have the condition. If you only have one, then you are a carrier of the disease, which means you can still pass the illness on to your children

Question 14

List the process of selective breeding

Answer 14

1) Two organisms are selected with desired characteristics
2) The two organisms are bred together
3) The offspring who most prominently display the desired characteristics are bred with another organism with those characteristics
4) The process is repeated over several generations
5) Eventually, a new breed of the organism is produced

Question 15

What are some advantages of selective breeding?

Answer 15

Advantages:

• more individuals within a breed
• variety possess desirable characteristics and the breed
• variety becomes more useful eg more food from a group

Question 16

What are the disadvantages of selective breeding?

Answer 16

• reduced gene pool (means there’s less variation in a population, and if a genetically inherited disorder is present, it will be common)
• reduced gene pool also means the population may be more vulnerable to future diseases as useful alleles that would have protected against the diseases have not been selected (they’ve been bred out by accident)

Question 17

What are the steps in genetically engineering an organism?

Answer 17

1. The gene with the desired characteristic (DC) is removed from the organisms DNA
2. A loop of DNA gets cut open and the DC gets inserted into it
3. This is now placed into a host bacteria (which is now genetically modified)
4. That gets placed in a fermenter
5. It multiplies in the fermenter

Question 18

Name some advantages and disadvantages of genetic engineering

Answer 18

Advant