Cells and organisms
Why are viruses considered non-living?
Which hormone is responsible for secondary sexual characteristics in males?
Testosterone
What is the difference between sexual and asexual reproduction?
Features of asexual reproduction (converse accepted)
- No fertiilization
- No gametes
- Only one parent required
What is a gene?
Section of DNA that codes for a particular feature/protein/trait
What is a community?
Different species in a habitat
A group of similar cells working together to perform a function
What are organs/tissues that produce hormones called?
Glands
Arrange these from smallest to largest
Egg, Zygote, Sperm, Fetus, Embryo
Sperm --> Egg --> Zygote --> Embryo --> Fetus
Where does translation occur?
At the ribosome
Which of the following is not always pymarid shaped?
a. Pyramid of energy
b. Pyramid of biomass
c. Pyramid of numbers
d. Pyramids of Egypt
c. Pyramid of numbers
Chloroplast
Cell wall
Permanent Vacuole
Explain 3 ways that the endocrine system is different to the nervous system.
- Endocrine system uses chemicals/nervous system uses electrical impulses
- Hormones travel through the bloodstream/nervous system uses electrical impulses and synapses
- Hormones can have many target organs/nervous system responses are very specific
- Hormonal effects can be long lasting/nervous reponses are short lived
- Endocrine reponses take longer/Nervous responses are immediate
Give three adaptations of the sperm.
- Tail/Flagellum
- Haploid nucleus
- Mitochondria in the midpiece
- Acrosome containing digestive enzyme
White colour is recessive to Purple in plants.
A white plant was crossed with a plant of unknown genotype.
50% of the offspring were purple.
What is the genotype of the unknown?
Heterozygous
What is the correct definiton of biological species?
Hint: there are 2 things that must be mentioned
Individuals that can mate and produce fertile offspring
Name 3 types of cell walls and the kingdom of the organism that have them.
Cellulose - Plants
Peptidoglycan - Bacteria/Prokaryote
Chitin - Fungi
On a hot day, do you have high or low ADH release? Why?
High
Lowers urine volume
How is the placenta maintained during pregnancy?
Hint: Name the hormone involved and what produces it
Progesterone
Corpus leutum does not break down, developed placenta then starts to produce progesterone
Which enzyme is involved in protein synthesis?
Name 2 things it does.
RNA polymerase
- Unwinds double helix
- Lines up complementary nucleotides along the template strand of DNA
What is the difference between bioaccumulation and biomagnification?
Bioaccumulation - accumulation of materials within 1 individual over time
Biomagnification - increase in concentratin of materials in individuals occupying higher trophic levels in a food chain
Explain how it is possible that almost all cells have the same DNA but can have different features?
Different genes from the entire DNA set is activated
This means different proteins are produced giving cells different features/specializations/adaptations
Give 3 effects of adrenaline along with their uses.
- Pupil dilation/widening --> sharper vision
- Increased heart rate --> More oxygenated blood pumped to muscles
- Vessel constriction for non-essential organs --> blood flow diverted to muscles
- Conversion of glycogen to glucose --> Increase glucose for increase muscular respiration
How does the developing fetus exchange materials with the mother?
Hint: What materials are carried by which blood vessels/where does exchange occur?
Umbilical cord and placenta
Umbilical artery --> high in co2, urea
Umbilical vein --> high in o2, amino acids, antibodies, glucose
Placenta is thin with villi, surface area for exchange without contact with blood
Two parents of different blood types had a offspring with the blood group A. Which of the following is not a possible combination of parental genotypes?
a. AB and OO
b. AA and BO.
c. AO and BB.
d. AB and BO.
c. AO and BB
Which bacteria is responsible for the conversion of ammomiun to nitrite to nitrate?
A. Nitrogen fixing bacteria
B. Decomposers
C. Nitrifying bacteria
D. Denitrifying bacteria
C. Nitrifying bacteria