CROSSING OVER INCREASES

• LIFE SPAN

• GENETIC VARIATION

• THE NUMBER OF OFF-SPRING

• ALL ARE TRUE

What is it called when a sperm and egg meet?

• meiosis
• fertilization
• cell division
• mitosis

A heterozygous long-tusked elephant is crossed with a homozygous recessive short-tusked elephant. What is the probability of the offspring having short tusks?

• 0%
• 25%
• 50%
• 75%

The chromosomes that pair up during meiosis, are called __________ chromosomes.  

• homozygous 
• asexual
• homologous
• genes

Which letter(s) in the diagram correspond to cells that are haploid? 

• A
• B
• C
• A and B

Females have ____ and males have _____ chromosomes.

• XX, XY
• XY, XX
• XX, XX
• XY, XY

What you see, or the physical appearance.

• Genotype
• Phenotype
• Homozygous
• Heterozygous

A human being has a somatic cell that has 46 chromosomes.  What is the haploid number found in a gamete?

• 23
• 46
• 69
• 92

What is this?

• Trisomy 13
• Monosomy 21
• 47, XXY
• Trisomy 21

In a pedigree, what shape represents a male?

• circle
• square
• triangle
• diamond