Year 10 Biology Practice Exam

What is the probable genetic makeup of a brown-eyed father, a blue-eyed mother, and their brown-eyed children?

Blue eyes are represented by the dominant allele in humans.

What color eyes would someone have if their genotype is bb?

The base pairing rule states that A (adenine) pairs with __________.

What are nucleotides made up of?

Match the following pairs according to the base pairing rule:

How many chromosomes are in human sex cells?

Maternal chromosomes are referred to as sex chromosomes for males.

What shape does DNA resemble?

What is the definition of translation?

If dimpled cheeks (D) are dominant to non-dimpled cheeks (d), what proportion of offspring with dimpled cheeks may one expect if two non-dimpled individuals mate?

How many chromosomes are present in human skin cells?

What percentage of straight-fingered chimpanzees would you expect if a heterozygous straight (Ss) and a homozygous bent (ss) mate?

What does the phenotype of an allele represent?

What is the complementary base sequence for the DNA strand G A T C A?

The cells produced by meiosis are called ________ and have ________ chromosomes.

Match the allele symbols with the coat colors in guinea pigs:

Year 10 Biology Practice Exam - Study Notes

Dominant and Recessive Traits (Eye Color): Brown eyes are dominant over blue; a brown-eyed man with a blue-eyed woman having 8 brown-eyed children likely has a genotype (Bb) and the woman (bb).
Genotypes and Phenotypes: A genotype of Bb (brown gene represented by B and blue gene represented by b) results in brown eyes. A genotype of bb (two copies of the recessive blue-eyed gene) results in blue eyes.
Base Pairing Rules (DNA): Guanine (G) pairs with cytosine (C), and adenine (A) pairs with thymine (T) in DNA structure.
Nucleotide Components: Nucleotides are composed of bases, phosphate, and a sugar.
Chromosome Numbers (Humans): Human body cells (somatic cells) have 46 chromosomes. Sex cells (gametes) have 23 chromosomes.
Sex Chromosomes: Females have XX chromosomes. Males have XY chromosomes.
Transcription vs. Translation: Transcription is copying the DNA message into RNA, while translation reads the RNA code to build proteins. Meiosis is the process of creating gametes (sex cells) with half the number of chromosomes.
Homozygous vs. Heterozygous: Homozygous means having two identical alleles (e.g., BB or bb), while heterozygous means having two different alleles (e.g. Bb).
Example Punnett Square: A cross between a heterozygous black-coated guinea pig (Bb) and a homozygous brown-coated guinea pig (bb) produces 50% black and 50% brown offspring.

Test your understanding of genetic concepts such as dominant and recessive traits, genotypes and phenotypes, and the structure of DNA. This practice exam covers essential topics like base pairing rules, chromosome numbers, and the process of transcription and translation. Prepare yourself for your Year 10 biology exam with these focused study notes.