Biology - DNA

What does DNA stand for?

Dexoyribonucleic Acid

What is DNA

The molecule that carries genetic information for the development and functioning of an organism

Where is DNA found

Mainly in the nucleus, but also in mitochondria

What does DNA contain?

Instructions that determine the characterisitcs of living things

What is the structure of DNA

A double-stranded double helix made of four type of nucleotides

What is a compartmentalisation

The separation of different cellular functions into different areas of the cell

What is the function of nuclues?

Stores genetic information and controls cells activities

What is the function of mitochondria

Produce chemical energy

What is the function of ribosomes

Assemble proteins

What cellular processes does the nuclues regulate

Growth and metabolism

What are nucleotides

The building blocks of DNA

What are the four DNA nucleotides

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

What forms when nucleotides join together

A nucleic acid chain

What joins nucleotides together?

Sugar and phosphate groups

What is the sugar-phosphate backbone

The sides of the DNA “Ladder”

What forms the rungs of the DNA ladder?

Paired nitrogen bases

What type of bond holds bases together

Hydrogen bonds

What shape is formed when twon nucleic acid strands wind together

Double helix

Which base pairs with Adenine

Thymine

Which base pairs with Cytosine

Guanine

What are complementary base pairs

A-T and G-C

Why are DNA strands complementary

The sequence on one strand determines th matching sequence on the other

What memory trick helps remember DNA base pairing?

“Take Away (T-A) on the Gold Coast (G-C)

Who captrued Photo 51

Rosalind Franklin

What technique did Rosalind Franklin use

X-ray crystallography

What did Photo 51 reveal

DNA has a helical structure

Who proposed the double-helix model of DNA

James Watson and Francis Crick

When was the double-helix model proposed

1953

Who received the 1962 Nobel Prize for DNA structure research?

Watson, Crick and Wilkins

Why didn’t Roaslind Franklis receive a Nobel Prize

She died before the prize was awarded

What are chromosomes made of?

DNA wrapped around histone proteins

Where are chromsomes located

In the nuclues

What does a single chromosome contain

One DNA molecule

What are histones

Proteins around which DNA is wrapped

Why is DNA wound into chromosomes

To fit inside the nuclues

What is a gene

A section of DNA that contains instructions for a specific protein

What determines the genetic code

The order of DNA bases

What determines the amino acid sequence of a protein

The sequence of DNA bases

What is a locus

the position of a gene on a chromosome

Do member of the same species have genes at the same loci

Yes

How do different genes vay

By base sequence and length

What are proteins responsible for

Cell structure, growth, survival and function

Give two examples of proteins

Enzymes and memebrane proteins

How do proteins affect characterisitics

They determine traits such as skin, eye and hair colour

What is non-coding DNA

DNA that does not code for proteins

Does all DNA code for proteins

No

What is a genome

An organism’s complete set of DNA

Does the genome include coding and non-coding DNA

Yes

What carries genetic information

DNA

What are genes

Instructions for making proteins

What do proteins do

Perform functions within cells and the body

Where are most genes found

On chromosomes in the nuclues

How many copies of each chromosome do most organims inherit

Two

What is a maternal chromsome

A chromosome inherited from the mother

What is a paternal chromosome

A chromosome inherited from the father

What are homologous chromsomes

Chromosome pair that have the same genes at the same loci

what features do homologous chromosomes share

Similar size, centromere position and gene locations

What does diploid (2n) mean

Having two copies of each chromosome

What cells are diploid

Most body (somatic) cells

What does haploid (n) mean

Having one copy of each chromsome

What cells are haploid

Gametes (sperm and egg cells)

How does the haploid number compare with the diploid number

It is half the diploid number

How many chromosomes are in a human body

46

How many chromsome pairs do humans have

23 pairs

How many pairs are autosomes

22 pairs

What are autosomes

Chromosomes 1-22

How many sex chromosomes do humans have

2 (1 pair)

What sEx chromosomes do females have

XX

What sEx chromsome do males have

XY

How many chromosomes are in human gametes

23