Additinal science Biology

Mitosis

Cells need to divide for growth and repair.

Body cells also known as SOMATIC CELLS ans contain a full set of CHROMOSOMES (Diploid).

Sex cells have half the genetic content of a somatic cell (Haploid).

MITOSIS is CELL DEVISION one somatic cell divided to produce two somatic cells, each with a full set (Diploid) of chromosomes.

Meiosis

MEIOSIS is the type of cell division that produces SEX CELLS.

One DIPLOID cell divides to produce four HAPLOID cells that are not genetically identicle.

Meiosis is important in producing offsprings that are not genetically identicle to the parents.

TOP TIP,

mEiosis produces Egg cells. miTOSis produces TOE cells!

Stem Cells

Cells are only able to undergo a certain number of divisions before they die.

The number of divisions they may indergo is determined by genetics.

This is the the HAYFLICK LIMIT.

STEM CELLS and cancer cells differ in that they do not have a Hayflick limit.

A stem cell can DIFFERENTIATE into any cell type.

Some animals have are able to regenerate whole limbs or body parts.

Examples of such animals include spirders, worms and reptiles.

This is relatively rare phonomenon as most adult organisms do not have such an avaliability of stem cells in the body.

Continuous Data

Height is a CONTINOUIS VARIABLE. This means there is a RANGE OF DATA.

Height in humans is affected by a number of factors such as genes, hormones and nutrition.

We use a SCATTER GRAPH fpr continuous data and drew A LINE OF BEST FIT. A line of best fit goes through as many of the points as possible.

Shoe size is a DISCRETE. This means the measurments fit into certain categories.

When drawing a graph for discrete data, we tend to use a BAR CHART.