21 questions. Try each one, then open the answer to check yourself and read the explanation.
When two genes for the same character (alleles) are contained in the same individual. The character that shows is known as
Answer: B (dominant character)
When two different alleles are present, the one that is expressed is the dominant one; the hidden one is recessive.
In Nigeria, a tropical rain-forest can be found in
Answer: D (Aba)
Rainforest is in the wet south of Nigeria; Aba is in Abia State. Sokoto, Kaduna and Abuja are in savanna zones.
The sum total of the biotic factors that affect living things is referred to as
Answer: A (environment)
Everything around an organism that affects it is its environment. Lithosphere, hydrosphere and atmosphere are the land, water and air.
Hygrometer is an ecological instrument that measures
Answer: B (humidity)
A hygrometer measures relative humidity. Rainfall uses a rain gauge, temperature a thermometer and light a photometer.
Which of the following air pollutant causes acid rain?
Answer: A (Sulphur dioxide)
Sulphur dioxide dissolves in rain water to form sulphurous and sulphuric acid, the main cause of acid rain.
Which of the following does not have a well-developed tissue?
Answer: A (Moss)
Moss is a bryophyte with no true vascular tissue. Ferns, the whispering tree (a conifer) and maize all have xylem and phloem.
Which of the following is air borne?
Answer: D (tuberculosis)
Tuberculosis spreads through droplets in the air. Malaria and yellow fever are spread by mosquitoes and cholera by dirty water.
Candida albicans is a?
Answer: B (Fungus)
Candida albicans is a yeast, a fungus that causes thrush (candidiasis).
All of these are vertebrates except
Answer: C (Star fish)
The starfish is an echinoderm with no backbone. Lizards, rats and tilapia are vertebrates.
Which of the following deaminates
Answer: C (liver)
The liver removes the amino group from excess amino acids (deamination) and turns it into urea; the kidney only excretes the urea.
The cervical vertebrae invariably number
Answer: B (7)
Almost all mammals, including humans, rabbits and even giraffes, have seven cervical (neck) vertebrae.
What force is responsible for the movement of water to the top of tall trees?
Answer: A (transpiration pull)
Water evaporating from leaves pulls a continuous column of water up the xylem; this transpiration pull lifts water to the tops of tall trees.
Antibodies are mammalian blood are formed by
Answer: B (white blood cells)
Antibodies are made by lymphocytes, a type of white blood cell.
Which of the following liquids supplies cells in the tissues of a mammal with oxygen and nutrients
Answer: A (blood)
Blood carries oxygen (in red cells) and nutrients (in plasma) to the tissues.
The fly and grasshoppers have mouth parts adapted for
Answer: C (lapping and chewing)
The housefly laps up liquid food and the grasshopper bites and chews leaves, so together: lapping and chewing.
The sponging and lapping mouth pars occurs in
Answer: C (housefly and lapping)
The housefly has sponge-like labella that soak up and lap liquid food.
The following is not an example of sex-linked character
Answer: D (height)
Colour blindness and haemophilia are carried on the X chromosome (and the book counts baldness too); height is controlled by many genes on other chromosomes.
Which of the following is a vestigial organ
Answer: A (appendix)
The human appendix has lost its original digestive function, so it is vestigial.
In which of the following flower parts does meiosis occur?
Answer: A (Anther)
Pollen grains (male gametes) are formed by meiosis inside the anther.
The release of useful substances from cells of an organism is called
Answer: D (secretion)
Secretion releases useful substances such as enzymes and hormones; excretion removes waste.
A box was left in the lawn for two days. When the box was removed the grass under it turned yellow due to lack of
Answer: B (light)
Without light the grass cannot make chlorophyll or photosynthesise, so it turns yellow.