Ocr As Levle Biology Keywords

Front 1

Diffusion

Back 1

The net movement of molecules/ions down its concentration gradient- PASSIVE

Front 2

Facilitated Diffusion

Back 2

Movement of a substance through a protein channel which provides a hydrophilic pathway – PASSIVE

Front 3

Osmosis

Back 3

The net movement of water molecules from an area of high concentration to an area to an area of low concentration through a partially permeable membrane

Front 4

Active Transport

Back 4

The movement of molecules/ions through transport proteins against their concentration gradient(USES ATP)

Front 5

Endocytosis

Back 5

The movement of bulk liquids/solids into a cell by the indentation of the fluid mosaic model to form vesicles contain the substance(USES ATP)

Front 6

Exocytosis

Back 6

The movement of bulk liquid out of a cell by the fusion of vesicles with the fluid mosaic model (USES ATP)

Front 7

Homologous Pairs

Back 7

A pair of chromosomes in a diploid cell that have the same structure with the same genes in the same location

Front 8

Stem Cell

Back 8

A cell that has not differentiated and is able to divide to form a specialised cell

Front 9

Differentiation

Back 9

The development of a cell to become specialised for a particular function

Front 10

Tissue

Back 10

A group of different types cells which work together to perform a particular function

Front 11

Organ

Back 11

A group of different tissues that work together to perform a particular function

Front 12

Organ System

Back 12

A group of organs that work together to carry out a particular function

Front 13

Tidal Volume

Back 13

The volume of air breather in and out in one typical breath

Front 14

Vital Capacity

Back 14

The maximum volume of air that can be breathed in and out in a one full breath

Front 15

Single Circulatory System

Back 15

A circulatory system in which the blood only passes through the heart once in a complete circuit of the body

Front 16

Double Circulatory System

Back 16

A circulatory system in which the blood passes through the heart twice in a complete circuit of the body (Systemic and Pulmonary)-HUMAN

Front 17

Closed Circulatory System

Back 17

A circulatory system in which the blood is always enclosed in a blood vessel

Front 18

Transpiration Stream

Back 18

The continuous movement of water from the soil up through the xylem to the air

Front 19

Active Loading

Back 19

Movement of sucrose into sieve tubes using active transport, carried out by the protein membrane of companion cells

Front 20

Plant Source

Back 20

An area in a plant where sucrose is produced e.g. the leaves

Front 21

Plant Sinks

Back 21

An area in a plant where sucrose in consumed e.g. roots

Front 22

Pits

Back 22

A part of a xylem element wall in which there is no lignin

Front 23

Stele

Back 23

The central (cross shaped) area of a root containing the xylem and phloem

Front 24

Lignin

Back 24

A strong waterproof substance found in the walls of xylem vessels

Front 25

Endodermis

Back 25

Outer layer of the stele in a plant root

Front 26

Apoplastic Pathway

Back 26

A route taken by water as it moves across a plant tissue by passing through cell walls and the spaces between the cells

Front 27

Symplastic Pathway

Back 27

A route taken by water as it moves across a plant tissue by passing through the cell’s cytoplasm

Front 28

Plasmodesmata

Back 28

A fine strand of cytoplasm that linked through cell walls connecting neighbouring cells

Front 29

Carbominohaemoglobin

Back 29

A compound formed when CO2 has bonded with haemoglobin to increase the amount of CO2 that can be removed from the cell

Front 30

Haemoglobnic Acid

Back 30

A compound formed when hydrogen ions bonds with haemoglobin

Front 31

Dissociation Curve

Back 31

A graph showing the percentage saturation of a blood pigment e.g. haemoglobin and oxygen

Front 32

Oxyhaemoglobin

Back 32

The compound formed when oxygen bonds with haemoglobin

Front 33

Oedema

Back 33

A build-up of lymph in the tissues caused by poor drainage from the lymphatics

Front 34

Lymphatics

Back 34

A vessel containing valves which transports lymph back into the blood stream

Front 35

ECG

Back 35

Electrocardiogram; a recording of the hearts electrical activity

Front 36

Cardiac Cycle

Back 36

• Right Atrium

• Right Ventricle

• Lung

• Oxygenated blood left atrium

• Left ventricle

• Tissues

Front 37

Surfactant

Back 37

A liquid secreted by some alveoli to reduce surface tension to prevent alveoli from sticking together

Front 38

Pleural Membrane

Back 38

One of the membranes that surrounds the lungs keeping them airtight

Front 39

Pleural Fluid

Back 39

A viscous fluid between two pleural membranes that surround the lungs

Front 40

Karyotype

Back 40

The picture taken of the chromosomes of an individual during mitosis, the pictures are then arranged in their pairs from largest->smallest

Front 41

Allele

Back 41

A variation of the same gene

Front 42

Totipotent

Back 42

When a stem cell is able to divide to form any of the different types of specialised cells in the body

Front 43

Spindle Fibre

Back 43

A structure made up of microtubules that is formed during cell division and move and positions the chromosomes to the equator for variation

Front 44

Centromere

Back 44

The place where two chromatids are held together, and where spindle fibres attach during cell division

Front 45

Fluid Mosaic Model

Back 45

Model of the plasma membrane that suggest that all molecules contained are continually moving

Front 46

Organelle

Back 46

A structure inside of a cell that has a specialised function

Front 47

Cytoskeleton

Back 47

The network of protein fibres found within cells that gives structure and shape to the cell

Front 48

Phospholipid bilayer

Back 48

The basic structural component of cell membranes. It consists of two layers or phospholipid molecules. Proteins are embedded in this layer.

Front 49

Cell Cycle

Back 49

The events that take place as one parent cell divides to produce new cells which then grow to full size

Front 50

Mitosis

Back 50

The process of nuclear division where two genetically identical nuclei are formed from one parent cell nucleus

Front 51

Meiosis

Back 51

The process of nuclear division where four haploid cells with different genetic information in are produced from one parent nucleus

Front 52

Inspiration and Expiration

Back 52

The terms used to describe breathing in and out.

Front 53

Sinoatrial Node

Back 53

The heart’s pacemaker. Small patch of tissue that sends out waves of electrical excitation at regular intervals to initiate contractions

Front 54

Blood

Back 54

Plasma held in the heart and blood vessels.

Front 55

Tissue Fluid

Back 55

Plasma that bathes the cells of individual tissues.

Front 56

Lymph

Back 56

Plasma that is held within the lymphatic system.

Front 57

Bohr Effect

Back 57

The change in the shape of the oxyhaemoglobin curve when carbon dioxide is present- this causes the oxyhaemoglobin to release more oxygen more readily.

Front 58

Xylem

Back 58

A plant transport tissue that carries water from the sink to source, consists of hollow columns of dead cells lined end-to-end and reinforced with lignin.

Front 59

Phloem

Back 59

A plant transport tissue that carries the products of the photosynthesis (sucrose) from source to sink, consists of sieve tube elements and companion cells.

Front 60

Cohesion

Back 60

The attraction of water molecules to one another.

Front 61

Adhesion

Back 61

The attraction of water molecules to the walls of the xylem.

Front 62

Transpiration

Back 62

The loss of water by evaporation from the aerial parts of a plant.

Front 63

Xerophyte

Back 63

A plant that is adapted to reduce water loss so that it can survive in very dry conditions.

Front 64

Translocation

Back 64

The transport of nutrients throughout the plant in the phloem tissue.