EduNinjaThis redwood tree (Sequoia sempervirens) was blown over in 1936, but five side branches formed new roots and are now separate trees.
Three of the new trees formed from side branches of the original tree
If the genomes of the five new trees were sequenced, predict with a reason how similar they would be to each other.
Which diagram(s) represent(s) processes used in asexual reproduction?
I.
II.
III.
I only
I and II only
II only
I, II and III
Ultraviolet (UV) light can penetrate cells, causing DNA damage. This effect can be reduced by using sunscreens or covering skin with clothing.
In an experiment to look at the effect of different treatments to reduce UV damage to DNA, yeast fungus (Saccharomyces cerevisiae) was used as the test organism. Six Petri dishes with agar were inoculated with yeast in sucrose solution. The Petri dishes were labelled according to the treatment applied to the lid, with sunscreen (Sun Protection Factors SPF15 or SPF50), cloth (polyester or cotton) or control (no treatment). Control 1 was placed in the dark and all the other Petri dishes were placed in direct sunlight for 6 hours. The dishes were then incubated for three days. The image shows yeast colonies that grew on the agar in one of the Petri dishes. The bar graph shows the number of yeast colonies present per Petri dish.
Describe how yeast cells reproduce.
Which is the best definition of a clone?
Two organisms sharing the same parents
Groups of phenotypically identical organisms
Cells derived by mitosis from a single parent cell
Multiple gamete cells produced by an individual
A two-cell sea urchin (Echinoidea) embryo was physically separated by scientists into two cells. Each cell, through further embryonic development, became an adult sea urchin.
What is the relationship between the two adult sea urchins?
They are equivalent to non-identical twins.
Half of the genes would be the same.
Both adults would have haploid cells.
They are clones.
The micrograph shows onion (Allium cepa) meristematic tissue.
Meiosis is another type of cell division. List two structures in which meiosis takes place in a flowering plant such as an onion.
1.
2.
Define pollination.
Outline how cross-pollination can be promoted by flowering plants.
Cherry trees (Prunus avium) have two self-incompatibility alleles. What benefit do self-incompatibility alleles have?
They decrease genetic variation.
They prevent inbreeding.
They decrease the chances of mutations taking place within the gametes.
They prevent the plant from releasing pollen at certain times of the year.
A cross-section of a flower is shown.
What is structure Y?
Anther
Nectary
Style
Stigma
The diagram shows the male reproductive system in front view.
Which structures are indicated by the letters X, Y and Z ?
X
Y
Z
testis
sperm duct
seminal vesicle
epididymis
sperm duct
prostate gland
testis
urethra
prostate gland
epididymis
urethra
seminal vesicle
Sketch the hormone changes between days 13 and 28 on the graphs below for a woman in her normal menstrual cycle.
