Chapter B13- Reproduction Flashcards Preview

GCSE Biology > Chapter B13- Reproduction > Flashcards

Flashcards in Chapter B13- Reproduction Deck (12):

What does asexual reproduction not use?

What is mitosis?

What does this cell division process make?

What is asexual reproduction called in prokaryotes?

What does meiosis only make?

What does meiosis half?

What does this cell division cause?

What happens to the DNA in meiosis?

What is the difference between meiosis and mitosis?

Sex cells (gametes)

The method of cell division in eukaryotes

Cloned cells (two identical daughter cells)

Binary fission

Sperm or egg cells (gametes)

The amount of DNA

Genetic division

The DNA of a cell in ovary or testes is replicated

Meiosis leads to non identical cells being formed while mitosis leads to identical cells being formed.


What does sexual reproduction involve?

What are the gametes in animals?

What are the gametes in flowering plants?

What happens in sexual reproduction?

What does asexual reproduction involve?

What does asexual reproduction not involve?

What does this then lead to?

What process is only involved in asexual reproduction?

What three things happen when a cell divides to form gametes in meiosis?

The joining (fusion) of male and female gametes

Sperm and egg cells

Pollen and egg cells

There is a mixing of genetic information which leads to variety in offspring

Only one parent and no fusion of gametes

No mixing of genetic information

Genetically identical offspring (clones)


-Copies of the genetic information are made
-The cell divides twice to form four gametes, each with a single set of chromosomes
-All gametes are genetically different from each other.


What happens to the number of chromosomes when gametes join at fertilisation?

What does the new cell divide and so what happens to the number of cells?

What also happens as the embryo develops?

What are three advantages of sexual reproduction?

What are four advantages of asexual reproduction?

How do malarial parasites reproduce?

How do many fungi reproduce?

How do many plants reproduce?

They restore the normal number of chromosomes

Mitosis and the number of cells increases

The cells differentiate

-Produces variation in offspring
-If the environment changes variation gives a survival advantage by natural selection
-Natural selection can be speeded up by human in selective breeding to increase food production

-Only one parent needed
-More time and energy efficient as don't need to find a mate
-Faster than sexual reproduction
-Many identical offspring can be produced when conditions are favourable

They reproduce asexually in the human host but sexually in the mosquito

They reproduce asexually by spores but also reproduce sexually to give variation

They produce seeds sexually, but also reproduce asexually by other plants.


How many cells are made in meiosis?

How many cells are made in mitosis?

In what cells does mitosis occur in?

In what cells does meiosis occur in?

Why does mitosis occur?

Why does meiosis occur?

4 cells

2 cells

All cells except gametes

Gametes only

In all body cells for growth and repair

In gametes that carry genetic information for sexual reproduction.


What is a molecule?

What type of atom is DNA?

Where is DNA stored in and as what?

What does DNA code for?

What is the genome of something?

What are the three importance's of the genome?

What is DNA made of and what are these called?

What are the three parts of these?

What is a base?

What are the four bases?

Non metal atoms in covalent bonds


Stored in the nuclei as chromosomes

The sequence of amino acids that make a protein

The sum total of all their DNA

- It can replace faulty genes
-Search for causes of disease
-Track the origins of humanity

Small repeating units called nucleotides

1. A phosphate group (acidic)
2. A sugar molecule
3. One of four different bases

A family of compounds which have a ph of more than 7

A, T, C and G.


Which base does base A always bind to?

Which base does Base C always bind to?

What do three bases code for?

What is DNA and what is it made up of (concerning image)?

What is a gene?

What is it called when certain bases always bind to?

What does the order of bases control?

What is DNA made up of repeating?

How are proteins formed?

What is this order determined by?

What are proteins synthesized by?

What happens to other proteins in the cell?

Give two examples of proteins that this happens to?

Base T

Base G

One amino acid

A polymer made up of two strands forming a double helix

Small section of DNA on a chromosome

Complementary base pairing

The order in which amino acids are assembled to produce a particular protein

Nucleotide units

By joining amino acids together in a specific order

The DNA sequence of the gene for that protein


They are secreted from the cell

Hormones and antibodies.


What is a gene (in terms of DNA)?

What do genes determine?

What do the ribosomes now do?

What does this form?

What then happens to the protein?

What then happens to the polypeptide?

What does 3 bases code for?

What do ribosomes do to the code?

What is a mutation?

What two changes can mutations do?

Why are some mutations less harmful?

What are some characteristics controlled by?

What does the genotype operate at?

What are most characteristics the result of instead of what?

The length of DNA on the chromosome

The order of amino acids in a specific protein

They read the sequence and attach amino acids together in the correct sequence


It is now released into the cytoplasm, where it folds and can then carry out its role (eg as an enzyme)

It folds into a specific shape

One amino acid

Examine the code and put together the correct sequence of amino acids

A change in the DNA sequence

Change the structure of the polypeptide and make it inactive

Because their occur in non-coding DNA

A single gene

A molecular level to develop characteristics that can be expressed as a phenotype

Multiple genes interacting rather than a single one.


What is a homozygous?

What is a heterozygous?

What do most features need?

What happens if a dominant allele is present?

What are most genetic diseases?

What does this mean?

What is polydactyl?

What type of genetic disorder is polydactyl?

What is the genotype?

What is the phenotype?

What type of genetic disorder is cystic fibrosis?

What is cystic fibrosis?

When is a recessive allele only present?

When two of the same alleles for a gene are present

When different alleles are present for the same gene

2 alleles

It masks the effect of the recessive allele


Two copies of the recessive allele are needed before the disease is manifested

A genetic disease where the sufferer has six finger and toes

A dominant genetic disorder

A combination of alleles for a feature

A feature or characteristic coded for by a genotype

A recessive genetic disorder, where two copies of "c" are needed

A genetic disorder which you produce extra thick mucus in your organs that contain mucus

If another recessive allele is present as well.


What is the genotype?

What is the phenotype?

How many body chromosomes do males have?

What sex chromosomes do males have?

How many body chromosomes do females have?

What sex chromosomes do females have?

What is cystic fibrosis a disorder of?

What is antennal testing used to analyse?

What can't it detect?

Who is prenatal testing offered to?

What is down's syndrome caused by

Demonstrates the alleles present for a particular characteristic

The physical appearance resulting from inherited information

44 body chromosomes

X and Y sex chromosomes

44 body chromosomes

X and X sex chromosomes

The cell membranes

An individual's DNA or chromosomes before they are born

All inherited disorders

Offered to couples who may have an increased risk of producing a baby with an inherited disorder

A faulty chromosome.


What does neonatal testing involve and how is it obtained?

When is this used and why?

What is pre-implantation genetic diagnosis (PGD)?

What are the cells tested for?

What happens to embryos that don't contain the unwanted allele?

What is carrier testing used to identify and who is it offered to?

What are inherited disorders caused by?

Analysing a sample of blood taken by pricking the baby's heel

It's used just after the baby has been born. It is designed to detect genetic disorders that can be treated early

A procedure used on embryos before implantation. Several eggs are released and contracted by a doctor (the woman has to take fertility drugs)

The allele posing a risk

Implanted into the uterus to hopefully create a lower risk, full term pregnancy

People who carry a recessive allele, offered to those who have a family history of a genetic disorder

The inheritance of certain alleles.


What do you have two of in your bodies DNA and where?

What is used to describe dominant alleles?

What is used to describe recessive alleles?

What must an organism have to display recessive characteristics?

What is your genotype?

What is your phenotype?

What do genetic diagrams show?

What is produced at the end of a genetic diagram?

What do genetic diagrams only tell you and what don't they say?

Two version (alleles) of every gene in the body- one on each chromosome

Capital letter for dominant alleles

Small letter for recessive alleles

Both of its alleles must be recessive

The combination of alleles you have

What characteristics you posses

The possible alleles of offspring


Genetic diagrams only tell you probabilities. They don't say definitely what'll happen.


What are insertion mutations?

What does insertion change in bases?

What can this then change?

Why can insertions change more than one amino acid?

What are deletion mutations?

What does deletion change in bases?

What can this then do?

What are substitution mutations?

Where a new base is inserted into the DNA base sequence where it shouldn't be

Changes the way groups of three bases are "read"

This can change the amino acids that they code for

Because they can have a knock on effect on the bases further on in the sequence

When a random base is deleted from the DNA base sequence

Change the way that base sequences are read

Can have knock on effects further down the sequence

When a random base in the DNA base sequence is changed to a different base.