Unit 3 AOS 2 Biology: SAC 2 key terminology

Photosynthesis

Conversion of light energy (sunlight) into chemical energy (glucose).

Light dependent stage

First stage of photosynthesis. Occurs in the thylakoid membranes of the chloroplasts. It involves using light energy to make ATP. Other products are NADPH and oxygen.

Light independent stage (Calvin Cycle)

RUBISCO combines CO2 with RuBP to produce an unstable intermediate which splits into two PGA molecules. PGA is reduced to G3P using the energy from ATP and reduced NADPH. 5 carbons are recycled to form RuBP and one is discarded to later form glucose

Co-enzyme

A complex organic molecule which helps certain enzymes to function correctly

NADP+

carrier molecule that transfers high-energy electrons

NADPH

A loaded electron carrier that provides high-energy electrons.

ATP

(adenosine triphosphate) main energy source that cells use for most of their work

ADP + Pi

sunlight

initial source of energy in photosynthesis

Chloroplast

Site of photosynthesis

chlorophyll a and chlorophyll b

light absorbing pigments (particularly blue and red wavelengths)

thylakoids, grana

The inner flat sac like membranes of the chloroplast which are a site of the light dependent stage

Stroma

fluid portion of the chloroplast; outside of the thylakoids that is the site of the Calvin cycle

Light dependent stage - inputs

H2O, ADP + Pi, NADP+

Light dependent stage - outputs

Oxygen, ATP, NADPH

Light independent stage (Calvin cycle) - Inputs

CO2, NADPH, ATP

Light independent stage (Calvin cycle) - Outputs

Glucose, NADP, ADP + Pi, water

Rubisco

The most abundant protein on earth. Performs Carbon Fixation in the Calvin Cycle. It has an affinity for both CO2 and O2.

Photorespiration

Reaction in which rubisco attaches oxygen instead of carbon dioxide to ribulose bisphosphate (RuBp)

CAM plants

plants close their stomata during the day, collect CO2 at night, and store the CO2 in the form of malate until it is needed during the day for photosynthesis.

C4 plants

A plant that prefaces the Calvin cycle with reactions that incorporate CO2 into four-carbon compounds (malate), the end product of which supplies CO2 for the Calvin cycle.

C3 plants

A plant that uses the Calvin cycle for the initial steps that incorporate CO2 into organic material, forming a three-carbon compound as the first stable intermediate.

CRISPR

Clustered Regulatory Interspaced Short Palindromic Repeats: a collection of DNA sequences that tells Cas9 exactly where to cut

Cas9 protein

holds the guide RNA, helps it basepair to DNA and cuts the genomic DNA

Guide RNA (gRNA)

RNA which has a specific sequence determined by CRISPR to guide Cas9 to a specific site

Duty based approach

an approach to bioethics that aims to follow the rules or law relating to the issue.

consequence based approach

an approach to bioethics that aims to maximise positive outcomes while minimising negative outcomes

virtues-based approach

an approach to bioethics that emphasises on what is the 'moral' or 'right' thing to do.

integrity

honesty, decency

respect

Treating a person or their feelings with consideration

justice

Respecting the rights of others and giving them what is rightfully theirs

Beneficence

Doing good or causing good to be done; kindly action

Non-Maleficence

duty to do no harm