Cell Division + cell transport

Chromosomes

Structures found in the nucleus of cells, composed of DNA molecules which are divided into genes, Human cells contain 23 pairs of chromosomes

DNA

Deoxyribonucleic acid. Contains your entire genome that make up all of your characteristics

Allele

One of two or more versions of DNA sequence (a single base or segment of bases) at given genomic location

Mitosis

The process by which a cell divides and produces two identical daughter cells for repair and growth

Stage 1

Cellular growth (Cells increase their subcellular structures)

The parent cell duplicates its DNA

Stage 2

The chromosomes line up at the centre of the cell

Cell fibres pull each arm of the chromosomes apart to opposite sides of the cell and nucleus reforms around chromosomes

Stage 3

The cell membrane and cytoplasm splits into daughter cells

Diploid cells

cell with 46 chromosomes (2 sets of chromosomes)

Haploid cells

cells with 23 chromosomes (1 set of chromosome)

Meiosis

a type of cell division that results in four daughter cells not identical to parent cell each with half the number of chromosomes of the parent cell (haploids) , as in the production of gametes

stem cells

unspecialized cells that have the ability to differentiate into a wide variety of specialized cells

Diffusion

The passive movement of molecules from a region of higher concentration to a region of lower concentration down the concentration gradient.

Accuracy

how close the measurement is to the true value

precision

how close the measurements are to each other

Validity

if your values are describing what was supposed to be measured.

Resolution

the smallest unit on the equipment

systematic errors

a consistent repeated error. usually due to faulty equipment or poor methodology

random error

unpredictable errors that are not repeated. usually human error.

Why do cells require diffusion?

it allows them to gain the useful substances they require to obtain energy and grow, and lets them get rid of waste products.

What molecules can diffuse into a cell?

Oxygen

Co2

Water

Amino acid

Solute

a dissolved substance in the solvent

Solvent

a liquid used to dissolve a solute

Solution

a liquid mixture in which the solute is uniformly distributed within the solvent

Osmosis

The passive movement of water molecules from an area of high water potential to and area of low water potential across a partially permeable membrane

Explain what a partially permeable membrane is

A membrane that has gaps to allow some substances to pass through it

flaccid cell

water lost from cell, cell loses shape

turgid cell

cell gains water, swelled up cell

High water potential

Low concentration of solute (dilute solution)

Low water potential

High concentration of solutes (concentrated solution)

active transport

Active transport is the active movement of a substance from an area of low concentration to an area of high concentration against the concentration gradient