Cell Division Flashcards
Define alleles?
Alternative forms of genes
Define homozygous?
Homozygous alleles have identical information for a trait. An individual with the same alleles on homologous chromosomes (e.g., PP or pp) is said to be homozygous for the trait. The same
Define heterozygous?
Heterozygous alleles have different information for a trait. An individual with different alleles on homologous chromosomes (e.g., Pp) is said to be heterozygous for the trait
What number chromosome is the sex chromosome?
Sex chromosome are the 23rd pair
- In females, the 23rd pair consist of XX
- In males the, the 23rd pair consists of XY
Define mitosis?
Division of the cytoplasm to create 2 new identical cells (daughter cells)
Define meiosis?
Occurs in the gonads (testes and ovaries). Results in production of haploid cells and diploid cells. Meiosis occurs in two stages. Meiosis One: One haploid parent cell divides into two daughter cells. Meiosis Two: Haploid parents cells divided into 4 haploid daughter cells
Define cancer?
A disease caused by an uncontrolled division of abnormal cells in a part of the body
Define a malignant tumours?
They undergo metastases. They spread the cancerous cells to other parts of the body
Define Benign Tumours?
They do not metastasise. They do not spread
Name the type of cancer that arises from epithelial tissue?
Carcinoma cancer=basal cell cancer
Name the type of cancer that arises from melanocytes?
Melanoma=skin cancer
Name the type of cancer that arises from lymphatic tissue?
Lymphoma= lymphatic cancer
Name the type of cancer that arises from leukocytes?
Leukaemia=blood cancer
State three causes of cancer?
- environmental agents
- viruses
- genes
What number chromosome is the sex chromosome?
23rd pair
