B15- Reproduction Flashcards
What is sexual reproduction?
Joining of male and female gametes
What type of cell division is involved in sexual reproduction?
Meiosis
What type of cell division is involved in asexual reproduction?
Mitosis
What is meiosis?
Cell division that produces gametes- four daughter cells with a single set of chromosomes
What are the male and female sex chromosomes in humans?
XX-female
XY-male
What are the male and female gametes in plants?
Male- pollen
Female-ovule
What is the genetic material in cells called?
DNA
What is the structure of DNA?
Double helix
What is a gene?
A small section of DNA that codes for a specific amino acid sequence to make a specific protein
What are alleles?
Different forms of the same gene
What is a recessive allele?
An allele that needs to be present twice in order to be expressed
What is a dominant allele?
An allele that is always expressed
What is a genome?
The entire genetic material of an organism
What is a chromosome?
A long molecule made from DNA located in the nucleus of the cell
What does homozygous mean?
Two of the same alleles present in an organism
What does heterozygous mean?
Two different alleles present in an organism
What does genotype mean?
The combination of alleles an organism has
What does phenotype mean?
The physical expression of the genotype
What has the study of the whole genome allowed scientists to do?
Search for genes linked to diseases, track migration patterns and treat inherited disorders
What type of allele causes polydactyly?
Dominant allele
What is polydactyly?
Extra fingers or toes
What is cystic fibrosis?
Cell membrane disorder causing them to produce extra mucus
What type of allele causes cystic fibrosis?
Recessive allele
How many chromosomes are in a normal human body cell?
46 (23 pairs)
