VARIATION, REPRODUCTION AND NEW TECHNOLOGY

GAMETES- SEX CELLS 

CHROMOSOMES- CELLS INSIDE THE NUCLEUS, HUMANS HAVE 46 CHROMOSOMES

DNA- CHROMOSOMES ARE MADE UP OF DEOXYRIBONULEIC ACID, WHERE GENETIC INFORMATION IS STORED

PARENTS PASS ON GENETIC INFORMATION TO THEIR OFFSPRING IN THE GAMETES.

GENETIC INFORMATION IS KEPT IN THE NUCLEUS OF YOUR CELLS . THE NUCLEUS CONTAINS CHROMOSONES WHICH CARRY THE GENES THAT CONTROL THE CHARACTERISTICS OF YOUR BODY.

MOST CHARACTERISTICS ARE THE RESULT OF SEVERAL DIFFERENT GENES WORKING TOGETHER LIKE HAIR AND EYE COLOUR. DIFFERENT GENES CONTROL THE DEVELOPMENT OF DIFFERENT CHARACTERISTICS.

ASEXUAL REPRODUCTION- INVOLVES ONLY ONE PARENT , NO JOINING OF GAMETES AND NO VARIETY IN THE OFFSPRING. THE GENETICALLY IDENTICAL OFFSPRING OF ASEXUAL REPRODUCTION ARE CLONES. ASEXUAL REPRODUCTION IS COMMON IN PLANTS, SMALL ANIMALS AND BACTERIA.

SEXUAL REPRODUCTION INVOLES A MALE AND FEMALE GAMETE, THE TWO GAMETES JOIN TOGETHER IN ORDER TO FORM A NEW INDIVIDUAL. THE OFFSPRING INHERITS GENETIC INFO FROM BOTH PARENTS. THIS INTRODUCES VARIETY. IN PLANTS THE GAMETES FOR SEXUAL REPRODUCTION ARE FOUND IN THE OVULES AND POLLEN. IN ANIMALS THEY ARE CALLED OVA AND SPERM.

DIFFERENCES IN CHARACTERISTICS BETWEEN FAMILIES CAN BE AFFECETD BY ENVIRONMENTAL CAUSES AND GENETIC CAUSES

TISSUE CULTURE- TISSUE IS PUT IN AGAR GROWTH MEDIUM WITH NUTRIENTS AND AUXINS, SAMPLES DEVELOP IN TO TINY PLANTLETS WHICH ARE THEN PLANTED IN TO COMPOST 

EMBRYO TRANSPLANTATION- EARLY EMBRYO (CLUSTER OF IDENTICAL CELLS) IS SEPARATED. EACH CELL DEVELOPS INTO AN IDENTICAL EMBRYO, EACH EMBRYO IS IMPLANTED IN TO A SURROGATE MOTHER. IDENTICALLY CLONED OFFSPRING ARE BORN.

CLONING ADULT CELLS- MALE BODY CELL IS TAKEN AND THE DNA IS EXTRACTED. EGG CELL IS TAKEN AND THE NUCLEUS IS REMOVED. DNA IS FUSED WITH EGG CELL. THE FUSED CELL DEVELOPS INTO EMBRYO WHICH IS PLACED IN UTERUS OF SURROGATE MOTHER. OFFSPRING IS CLONE OF MALE ANIMAL.

GENETIC ENGINEERING INVOLVES CHANGING THE GENETIC MATERIAL OF AN ORGANISM.

STEP ONE: SMALL PIECE OF DNA CUT OUT OF CELL WITH AN ENZYME

STEP TWO: THIS IS TRANSFERRED INTO EITHER A BACTERIUM CELL OR TO ANOTHER ORGANISM. 

BENEFITS:

• MAKES PROTEINS WE NEED LIKE INSULIN
• IMPROVED FOOD VALUE
• IMPROVE GROWTH RATES OF PLANTS
• CROPS CAN BE GROWN WITH TOLERANCE TO EXTREME WEATHERS

DISADVANTAGES:

• POOR FARMERS CANNOT AFFORD TO MODIFY THEIR CROPS
• PEOPLE MAY NOT AGREE WITH INTERFERING WITH NATURAL GROWTH