Chapter 13 Flashcards
What is sexual reproduction?
it involves the joining (fusion) of male and female gametes producing genetic variation on the offspring
What is asexual reproduction?
it Involves only 1 parent, the offspring is identical to the parent. No fusion of gametes or mixing genetic variation in the offspring
What is mitosis?
a type of cell division that results in two daughter cells each having the same number and kind of chromosome as the parent nucleus (typical of ordinary tissue growth)
What is meiosis?
the two stage process of cell division that reduces the chromosome number of daughter cells. It is involved in making gametes for sexual reproduction
What happens in fertilisation?
the sperm enter the uterus through the cervix and travel to the egg tubes, if a sperm cell meets with an egg fertilization can occur
What is the structure of DNA?
it is a double helix with a sugar phosphate backbone
What does DNA store?
biological information in sequences of four bases of nucleic acid = A - adenine, T - thymine, C - cytosine, G - guanine
What is a genome?
a haploid set of chromosomes in a gamete or microorganism, or in each cell of a multi-cellular organism
What do genes control?
the development of different characteristics of an organism
What is a diploid?
a cell that has the full number of chromosomes
What is a haploid?
a cell that has half the number of chromosomes
What are alleles?
a form of gene
What is homozygote?
an individual with two identical alleles for a characteristic
What is a heterozygote?
an individual with different alleles for a characteristic
What is a genotype?
the genetic makeup of an individual for a particular characteristic
What is a phenotype?
the physical appearance/biochemistry of an individual for a particular characteristic
What is dominant?
a dominant allele will always be expressed in the phenotype even if only one of the alleles is inherited
What is recessive?
alleles that are only shown if their are two copies
What is a mutation?
a change in the DNA
What is a punnet square diagram used for?
to predict the outcome of a particular cross or breading experiment
What is the genetic crosses used for?
the test determines the genotype of an individual with a dominate phenotype
What is cystic fibrosis?
an inherited disorder that affects the lungs, digestive and reproductive system. Inherited through a recessive allele
What is polydactyly?
a dominant inherited disorder that results in babies born with extra fingers and / or toes
How are chromosomes arranged in the body’s cells?
they have one protein and one molecule of DNA, humans have 22 pairs of chromosomes
