A population that doubles in size at constant intervals is an indication of
- A. sigmoid growth
- B. exponential growth
- C. population explosion
- D. rapid growth
The soil type that contain nutrients which are not readily available for plants is
- A. alluvial
- B. clayey
- C. sandy
- D. loamy
Climax communities in a biotic succession are usually characterized by
- A. a constant change in the appearance of the communities
- B. different species that are constantly changing
- C. a stable composition of plant and animal species
- D. rapid changes in the plant and animal species
Grasses recover quickly from bush fires in the savanna because of their
- A. perennating organs
- B. rapid growth rate
- C. fibrous roots
- D. succulent stems
The causative agent of typhoid fever is
- A. salmonella
- B. entamoeba
- C. escherichia
- D. shigella
An organism which exhibits extracellular digestion is
- A. spirogyra
- B. paramecium
- C. amoeba
- D. rhizopus
A characteristic that best exemplifies the evolutionary advancement of mammals over other vertebrates is the
- A. viviparous mode of reproduction
- B. possession of paired limbs
- C. terrestrial mode of life
- D. possession of a heart
One primitive feature of the coelenterates is the possession of
- A. a dorsal mouth
- B. radial symmetry
- C. bilateral symmetry
- D. a false foot
Which of the following vertebrates has the most simple structured heart
- A. reptile
- B. fish
- C. mammal
- D. amphibian
The evidence that supports the advancement of ferns over mosses is derive from
- A. comparative anatomy
- B. molecular records
- C. biochemical similarities
- D. physiological records
The dominant phase in the life cycle of a bryophyte is the
- A. gametangium
- B. sporophyte
- C. gametophyte
- D. prothallus
The role of the Golgi complex in a eukaryotic cell is to
- A. conduct irons in and out of the cells
- B. transport genetic materials out of the cell
- C. provide attachment for ribosomal granules
- D. transport organic materials in and out of the cells
The part of the mammalian skin involved in temperature regulation is the
- A. sweat gland
- B. hair papilla
- C. hair follicle
- D. sebaceous gland
The intensity of competition among animals in a given area will increase with
- A. an increase in the frequency of disease outbreaks
- B. an increase in population size
- C. a decrease in immigration rate
- D. an increase in the emigration rate
Mendel’s second law of inheritance states that
- A. alleles combine randomly
- B. alleles segregates independently
- C. alleles seperate predictably
- D. chromosomes segregates independently
One advantage of variation in a species population is that individuals
- A. with favoured traits become dominant
- B. easily reach their reproductive age
- C. are easily recognised by mates
- D. are better adapted to changes
The two normal types of sex chromosomes are
- A. XXY and XYY
- B. XX and XYY
- C. XY and XXY
- D. XXand XY
In the transverse of a dicot sperm, the region lying between the endodermis and the vascular bundle is the
- A. parenchyma
- B. pericycle
- C. phloem
- D. hypodermis
The mammalian vein which starts with and ends in a capillary network is the
- A. pulmonary vein
- B. mesenteric vein
- C. renal vein
- D. hepatic potal vein
Which of the following produces both hormones and enzymes
- A. lleum
- B. pancreas
- C. gall bladder
- D. kidney
Water is necessary for a germinating seed because it
- A. promotes aerobic respiration
- B. activate the enzymes
- C. wets the soil for proper germination
- D. protects the seed from desiccation