Biology

Question 1

Chromosomes

Answer 1

have thousands of genes on them, and are composed of a chemical called DNA

Question 2

DNA

Answer 2

deoxyribonucleic acid

Question 3

Genes

Answer 3

are small sections of DNA on a chromosome, and provide “instructions” which ribosomes use to make proteins.

Question 4

What is DNA made up of

Answer 4

nucleotides, wound together in a double helix (like a twisted ladder).

Question 5

What is nucleotides made up of

Answer 5

sugar (called deoxyribose), a phosphate and a nitrogen base.

Question 6

The nitrogen bases are

Answer 6

Adenine (A), Thymine (T), Cytosine (C) and Guanine (G).

Question 7

ribosomes in groups of three, called a

Answer 7

codon
ribosomes “read” the codon to figure out the instructions for how to synthesize all of the different proteins that the cell needs.

Question 8

gene

Answer 8

a section of DNA that determines a characteristic.

Question 9

Even one different nucleotide in the gene could cause a totally different protein to be made. True or false

Answer 9

True

Question 10

DNA can make identical copies of itself in a process called

Answer 10

DNA replication. Without this, cell division (mitosis & meiosis) would be impossible.

Question 11

What does the acronym “DNA” stand for?

Answer 11

deoxyribonucleic acid

Question 12

Describe the structure of DNA

Answer 12

DNA is made up of nucleotides, wound together in a double helix (like a twisted ladder).

Question 13

Describe the function of DNA.

Answer 13

provide “instructions” which ribosomes use to make proteins.

Question 14

Describe the connection between DNA, Genes, Ribosomes, and Proteins.

Answer 14

Genes are a sections of DNA that ribosomes can read to make proteins

Question 15

Mitosis

Answer 15

• Occurs only regular body cells or somatic cells
• Allows organisms to grow and to replace damaged cells.
• Original cell is divided into two cells that are identical to the original cell.Each new cell has a full set of chromosomes.

Question 16

Meiosis

Answer 16

• Takes place in the cells of the testes and ovaries, which are the primary reproductive organs.
• Make sex cells(sperm & eggs) by taking a cell from an ovary or testes and “halving” the numbers of chromosomes to make two new cells.

Question 17

Explain why it is important that the DNA doubles before the cell begins meiosis?

Answer 17

To ensure that all of the important genetic information ends up in each of the new cells.

Question 18

Explain the significance of the crossing over (synapse) of the homologous pairs (tetrads) in Prophase I.

Answer 18

Homologous chromosomes trade pieces of genetic material, resulting in the alleles combiding , though the same genes are still present.

Question 19

What is nonjunction

Answer 19

Nonjunction occurs when two homologous chromosomes move to the same
pole during meiosis.They don’t separate equally.

Question 20

Differance between monosomy and trisomy

Answer 20

Trisomy is when you have an extra copy of a chromosome. Monosomy is when you are missing a copy of a chromosome.

Question 21

What is downsydrome

Answer 21

Down syndrome happens when the person has an extra 21 chromosome.

Question 22

Spermatogenesis Only

Answer 22

Symmetrical cytoplasm division
Takes days or week
Occurs in testicles
Less cytoplasm for les movement
Starts around puberty

Question 23

Oogenesis Only

Answer 23

asymmetrical cytoplasm division
take months or weeks
Occurs in ovary
more cytoplasm for movement
Starts before birth

Question 24

Whats in both Oogenesis and Spermatogenesis

Answer 24

4 cells are made in both of these processes, and each cell ends up with 23 chromosomes in it
Both through meiosis twice
have a chromatin

Question 25

When meiosis occurs in females, the cytoplasm is not divided equally among the resulting four cells. Explain why this is important.

Answer 25

More cytoplasm is sent to one of the eggs then the other three eggs because it's better to have one good bigger egg then 4 ok eggs.One egg needs to have enough nutrients to make it through the uterus without dying due to lack of nutrients

Question 26

What are sex chromosomes

Answer 26

Sex chromosomes contain genes that control the sex of an individual. Biological females have two equal sized “X” chromosomes. Biological males have two different sized sex chromosomes - one “X” and one “Y”.

Question 27

What is autosomes

Answer 27

Autosomes are the other 44 chromosomes inside the cell. They are not involved in sex determination and contain genes for other features, such as hair colour and height.

Question 28

What are the 5 main factors that determine the biological sex of an individual?

Answer 28

The chromosomes they have The gene on the chromosomes The hormones that are made The internal and external sex organs they were born with The secondary sex characteristics

Question 29

Crispr pros

Answer 29

fastest, easiest, and cheapest of the gene editing tool natural process that’s long functioned as a bacterial immune system. CRISPR to target not just viral DNA, but any DNA in almost any organism create new treatments for diseases linked to specific genetic errors, like cystic fibrosis or sickle cell anaemia not limited to humans

Question 30

Crispr cons

Answer 30

Repair process, called nonhomologous end joining, is prone to mistakes and can lead to extra or missing bases. Don’t know the long term effect Doesn’t always make just the intended changes CRISPR can cause many people to lose their job

Question 31

Intrauterine Insemination pros

Answer 31

- allows more sperm to reach the egg by using of a soft, small, and flexible plastic tube called a catheter - not painful - only a few minutes and allows patients to return almost immediately to regular activities -no limit on the number of treatment cycles.

Question 32

Intrauterine Insemination cons

Answer 32

- not recommended in cases where there is a low sperm count and/or blocked tubes. - increased risk of multiple pregnancies and of ovarian hyperstimulation syndrome (OHSS). - the success rate of IUI can vary significantly and depends on the age, the type of medication and the presence of other fertility problems.

Question 33

Vitro Fertilisation pros

Answer 33

- most effective techniques - accurate timing of fertility medication and careful ultrasound monitoring

Question 34

Vitro Fertilisation cons

Answer 34

- increased risk of multiple pregnancies and of ovarian hyperstimulation syndrome (OHSS). - the success rate of IVF can vary significantly and depends on the age, the type of medication and the presence of other fertility problems. - recommended for women affected by endometriosis, unexplained infertility, tubal blockage, and ovulation - One treatment cycle per patient - One additional cycle if carrying a baby for someone else

Question 35

A trait that is inherited

Answer 35

Eye colour

Question 36

A trait that is shaped by the environment

Answer 36

Language

Question 37

A trait that is both inherited and shaped by the environment

Answer 37

Height

Question 38

Each trait (eg. skin colour) is controlled by one gene True or False

Answer 38

False

Question 39

The different versions of genes are called alleles. True or False

Answer 39

True

Question 40

The probability of inheriting a certain characteristic is different for each child conceived by a couple. True or False

Answer 40

True

Question 41

Each parent contributes an equal amount of DNA to their child. True or False

Answer 41

True

Question 42

Mutations result in diseases and disorders. True or False

Answer 42

True and False

Question 43

Each of our cells has a copy of the DNA that was present in the first fertilised egg cell that our parents made. True or False

Answer 43

True

Question 44

Genes in some cells are switched off over time, to allow cells to specialise their functions.

Answer 44

True

Question 45

Phenotype

Answer 45

The physical description of the trait.E.G. Brown eyes or Blue eyes.

Question 46

Genotype

Answer 46

The letters assigned to each of the alleles that an individual has E.g. BB or Bb

Question 47

Homozygous (a.k.a. Pure)

Answer 47

The individual has two of the same alleles E.g. BB or bb

Question 48

Heterozygous (a.k.a. Hybrid)

Answer 48

The individual has two different alleles E.g. Bb