U1AOS1
What type of cell has no membrane-bound nucleus or organelles?
Prokaryotes
Which vascular tissue carries water and minerals from the roots to the leaves?
Xylem
What is the term for the different versions of the same gene?
Alleles
Name the three types of adaptation.
Behavioural, structural, physiological
Which university did Mr Punjwani go to?
Monash University
What do we call a stem cell that can become any cell type, including placental (extra-embryonic) tissue?
Totipotent
List the parts of the stimulus–response model, in order.
Stimulus → receptor → control centre → effector → response
How many chromosomes are in a human gamete, and what term describes this?
23, Haploid
What type of symbiotic relationship benefits one species and harms the other?
Parasitism
What is Ms Joy's first name?
Jincy
A red blood cell put in distilled water swells and bursts. Name the process and whether it becomes isotonic, hypotonic, or hypertonic
Osmosis, hypotonic
How do guard cells reduce water loss in a plant on a hot, dry day?
The guard cells lose water and become flaccid, which closes the stomata. This reduces transpiration.
Two heterozygous tall pea plants (Tt) are crossed. What is the expected phenotypic ratio of the offspring?
3 tall : 1 short
Give one advantage and one disadvantage of asexual reproduction.
Advantages: it’s fast, needs no mate and uses less energy. Disadvantage: offspring are genetically identical, so there’s little genetic diversity and the population is vulnerable to disease or environmental change.
Name the degrees that Mr Punjwani has:
Bachelor of Science, Honours, Master of Education
Name the type of diffusion glucose undergoes to move through the plasma membrane
Facilitated diffusion
Blood glucose rises after a meal. Explain how negative feedback brings it back to normal.
Beta cells in the pancreas detect the rise and secrete insulin. Insulin causes liver and muscle cells to take up glucose and store it as glycogen. As blood glucose falls, the stimulus is reduced, so less insulin is released.
Give two differences between the products of meiosis and mitosis.
Meiosis produces 4 cells; mitosis produces 2. Meiosis cells are haploid; mitosis cells are diploid. Meiosis cells are genetically different; mitosis cells are identical.
What is a keystone species? Predict what would happen if one were removed from an ecosystem.
A species that has a disproportionately large effect on its ecosystem relative to its abundance. Example: removing dingoes can lead to more foxes and kangaroos, which then causes overgrazing and loss of small native mammals. This cascade reduces biodiversity.
Name a cuisine in Mr Punjwani's top 3
Pakistani, Mexican, Japanese
Which cell cycle checkpoint makes sure all chromosomes are attached to spindle fibres before separation?
The M (spindle/metaphase) checkpoint
Name the hormone that increases water reabsorption in the kidneys, and the part of the nephron it acts on.
ADH (antidiuretic hormone); the collecting ducts (and distal tubules)
Two genes have a recombination frequency of 50%. What does this tell you about them?
They’re unlinked: either on different chromosomes or very far apart on the same chromosome
Name the three sources of genetic variation in sexual reproduction.
Crossing over, independent assortment, random fertilisation
What breed is Mr Punjwani's dog?
Kelpie