Cell Division and Inheritance Flashcards
What are chromosomes made from?
Chromosomes are made from DNA. Genes are short sections of DNA.
How are genetically identical cells produced?
Genetically identical cells are produced by a type of cell division called mitosis.
What is fertilisation?
In sexual reproduction, a male gamete fuses with a female gamete to produce a new cell. This is called fertilisation.
How are gametes produced?
Gametes are produced by a type of cell division called meiosis.
How many sets of chromosomes do gametes contain?
They contain a single set of chromosomes, whereas body cells contain two sets of chromosomes.
What does DNA stand for?
Deoxyribose nucleic acid.
What are DNA molecules like?
DNA molecules are large and complex. They carry the genetic code that determines the characteristics of a living thing.
Why can people be identified using DNA fingerprinting?
Except for identical twins, each person’s DNA is unique. DNA can be cut up and separated, forming a sort of ‘bar code’ that is different from one person to the next.
What is a gene?
A gene is a short section of DNA. Each gene codes for a specific protein by specifying the order in which amino acids must be joined together.
Where are chromosomes normally found?
They are normally found in pairs in body cells. Body cells divide by a process called mitosis.
What happens when a body cell divides by mitosis?
The genetic material is copied. The cell divides once to form two genetically identical body cells
When does mitosis occur?
Mitosis occurs during growth or to produce replacement cells.
What are gametes?
Gametes are sex cells.
How are gametes formed?
Cells in the reproductive organs (testes and ovaries in humans) divide to form gametes
What are male gametes?
Male gametes are sperm (produced in the testes)
What are female gametes?
Female gametes are eggs (produced in the ovaries)
What is the name of the type of cell division called that produces gametes?
The type of cell division that produces gametes is called meiosis
How many sets of genetic information do gametes contain?
Gametes contain one set of genetic information, while body cells contain two sets of genetic information.
What happens when fertilisation happens?
When fertilisation happens, a single body cell with new pairs of chromosomes is formed. The new cell then divides over and over again by mitosis.
What happens when animal cells differentiate?
Most types of animal cells differentiate at an early stage - they become specialised for a particular function and cannot change into different types of cell.
Can plant cells differentiate?
Yes. Many plant cells keep the ability to differentiate.
Can stem cells differentiate?
Stem cells can be made to differentiate to form different types of cell, such as nerve cells.
Where can human stem cells come from?
Human stem cells can come from human embryos or from adult bone marrow. They are able to develop into any kind of human cell.
Can stem cells be used in new treatments for conditions?
Stem cells have the potential to be used in new treatments for conditions such as Parkinson’s disease and paralysis.
