Why can't scientists be certain about how life began?
What are fossils? How can they be formed?
Many early forms of life were soft-bodied, which means they left ___ traces behind. What traces there were have been mainly ____ by _____ activity.
We can learn from fossils how ___ or how ____ _____ organisms have changed as ____ ____ on Earth.
EXTINCTION may be caused by:
New species arises as a result of...
Mendel proposed the ideas of separately inherited factors because?
Interpreting genetic diagrams
Alleles are what?
Homozygous means what?
Heterozygous?
Phenotype is the physical characteristics of an organism due to its genotype and environment
Genotype - how a set of alleles determines the physical characteristics of an organism
Embryo screening
Embryo screen evaluation
In body cells the ____ are normally found in pairs. Body cells divide by ______.
The chromosomes contain...
Mitosis process
Mitosis occurs during ____
Sex cells only have one set of .....
Meiosis occurs in the ____ or the ____ in humans to form GAMETES.
Meiosis process
Genetic diagrams are ____ models which can be used to predict the outcome of _____
When gametes join at fertilisation, a single body cell with new pairs of chromsomes are formed.
A new individiual then develops by this cell repeatedly dividing by ___
Most types of animal cells differentiate at an ____ stage BUT PLANT CELLS retain the ability to ____ throughout life.
In mature animals, cell division is mainly ____ to ____ and replacement
The cells of the offspring produced by ASEXUAL REPRODUCTION
are produced by ____ from the ____ cells. They contain the ____ alleles as the parents.
Chromosomes are made up of ____ which has a double ___ structure.
A gene is a small section of?
Are these genetic disorders caused by recessive or dominant alleles of the undesirable gene?
i) Polydactyly
ii) Cystic fibrosis
The chemical reactions inside cells are controlled by...
Each gene codes for a particular combination of _____ ____ which make a specific protein
During ____ respiration, chemical reactions occur that:
Most of the reactions in aerobic respiration take place in the mitochondria
Energy released by respiration is used by the organism through:
1) During exercise the changes in your body are:
2) What effect do these changes have on your body
Muscles store glucose as what?
Anaerobic respiration is?