MOD 5

Question 1

Sexual Reproduction (ad/dis)

Answer 1

reproduction involving a male and female sex. Offspring will inherit unique combination of genes. Male and female must encounter each other for reproduction to occur.

Question 2

Asexual Reproduction (ad/dis)

Answer 2

reproduction involving no sexes, and instead self-production. Produces large amounts of offspring quickly to take advantage of the environment. Less genetic variation as there is less variation in the population.

Question 3

DNA replication

Answer 3

DNA replication is the process by which the double stranded DNA molecule is unzipped by enzymes, and free nucleotides bind to each of the exposed backbones to create two identical DNA molecules.

Question 4

Helicase

Answer 4

Helicase responsible for the unzipping of the original DNA molecule in DNA replication.

Question 5

DNA polymerase

Answer 5

DNA polymerase in the presence of the free nucleotides, will attract them in DNA replication.

Question 6

Leading Strand

Answer 6

The leading strand represents the replicated molecule that moves in the direction of the replication fork and is continuously synthesised. (5-3 primer sequence).

Question 7

Lagging Strand

Answer 7

The lagging strand is the original strand which moves in the opposite direction of the replication fork and is discontinuously synthesised through Okazaki (short) fragments. (5-3 primer sequence).

Question 8

Genotype

Answer 8

A person’s genotype is their unique sequence of DNA.

Question 9

Phenotype

Answer 9

Phenotype refers to an individual’s observable traits, such as height, eye colour and blood type.

Question 10

Allele

Answer 10

the word that we use to describe the alternative form or versions of a gene.

Question 11

Autosomal

Answer 11

means that the gene in question is located on one of the numbered, or non-sex, chromosomes. (no X or Y)

Question 12

Recessive

Answer 12

Refers to a trait that is expressed only when genotype is homozygous; a trait that tends to be masked by other inherited traits.

Question 13

Dominant

Answer 13

Refers to a trait that is expressed when the genotype is homozygous or heterozygous; trait is never masked by other inherited traits.

Question 14

Homozygous

Answer 14

having two identical alleles of a particular gene or genes.

Question 15

heterozygous

Answer 15

having two different alleles of a particular gene or genes.

Question 16

Sex-Linked

Answer 16

Sex-linked, as related to genetics, refers to characteristics (or traits) that are influenced by genes carried on the sex chromosomes. (is X or Y)

Question 17

Gamete

Answer 17

a mature haploid male or female germ cell which is able to unite with another of the opposite sex in sexual reproduction to form a zygote.

Question 18

Mitosis

Answer 18

begins with two homologous chromosomes which is one chromosome from each parent (interphase). the pair then duplicates, becoming sister chromatids (prophase) which is followed by spindle fibres pulling each chromatid to a side of the cell (metaphase). the chromatids then seperate (anaphase), and produce two new cells each with two homologous chromosomes in them, one from each parent (telophase/cytokinesis).

Question 19

Meiosis 1

Answer 19

begins with 4 homologous pairs of chromosomes in one cell (prophase). Homologous chromosomes line up at the metaphase plate (metaphase). Homologues seperate to the opposite end of the cell after exchanging fragments (anaphase). two new cells form with two homologous pairs of chromosomes in each, all with non-identical sister chromatids (telophase/cytokinesis).

Question 20

Meiosis 2

Answer 20

chromosomes condense (prophase). Homologous pairs line up at metaphase plate (metaphase). Sister chromatids seperate to the ends of the cell (4 in each cell) (anaphase). Each cell separates creating 4 cells, each with two chromosomes (telophase/cytokinesis).

Question 21

Phosphate Backbone

Answer 21

A phosphate backbone is the portion of the DNA double helix that provides structural support to the molecule.

Question 22

Deoxyribose Sugar

Answer 22

Deoxyribose is a key building block of DNA. Its chemical structure allows for the replication of cells in DNA’s double helix configuration.

Question 23

Eukaryotic

Answer 23

eukaryote, any cell or organism that possesses a clearly defined nucleus.

Question 24

Prokaryotic

Answer 24

Prokaryote, any organism that lacks a distinct nucleus and other organelles due to the absence of internal membranes.

Question 25

Enzyme

Answer 25

a substance produced by a living organism which acts as a catalyst to bring about a specific biochemical reaction.

Question 26

Protein

Answer 26

It helps repair and build your body’s tissues, allows metabolic reactions to take place and coordinates bodily functions.

Question 27

Internal Fertilisation Adv/Dis

Answer 27

Will provide a more safer and protected environment for fertilisation but will require more energy from the parents.

Question 28

External Fertilisation Adv/Dis

Answer 28

Will provide a large number of gametes, increasing the chance for multiple successful offspring but the offspring are less safe in the environment.

Question 29

Fungi Reproduction

Answer 29

Many fungi reproduce asexually by producing specialised reproductive cells called spores. Yeasts, a type of fungi, reproduce asexually through a process called budding. A small bud or daughter cell forms on the parent yeast cell and eventually detaches to become a new, independent yeast cell.

Question 30

Bacterial Reproduction

Answer 30

Binary fission is a method of asexual reproduction in bacteria where a single bacterial cell divides into two identical daughter cells, each with a complete set of genetic material, resulting in exponential growth of the bacterial population.

Question 31

Protist Reproduction

Answer 31

In binary fission, a single-celled protist divides into two nearly identical daughter cells. The protist’s nucleus duplicates, and then the cell divides into two, each with its own nucleus, organelles, and genetic material.

Question 32

Co-Dominant

Answer 32

A co-dominant allele is one of two or more alleles of a gene that are both expressed in a heterozygous individual, and neither allele is dominant over the other. This means that both alleles contribute to the phenotype, resulting in a combined or blended expression rather than one allele masking the effects of the other.

Question 33

incomplete dominance

Answer 33

An incomplete-dominant allele is a type of allele in a gene pair where neither allele is completely dominant over the other. Instead, the heterozygous individual (with one of each allele) displays an intermediate or blended phenotype that is a combination of the traits associated with each allele, rather than one allele completely masking the other.

Question 34

DNA Profiling: Forensics

Answer 34

Suspects should be a complete match with the DNA sample taken from the crime scene if a conviction is to occur.

Question 35

DNA Profiling: Paternity

Answer 35

Children inherit half their chromosomes from each parent and thus should possess a combination of parental fragments.