11. List two physical properties of soil. list three conditions necessary for the germination of seed.

E. P BETHEL INTERNATIONAL SCHOOL- ACCRA NEWTOWN
END OF SECOND TERM EXAMINATION- 2020
INTEGRATED SCIENCE-JHS ONE
SECTION B (ESSAY) 6OMARKS
Answer any four questions in this section. Each complete question carries 15 marks.
2. a. i. State the reasons why some seeds are nursed.
(3mar
(2mar
(1x3.
(2mc
(2m
b. I. List three (3) conditions necessary for the germination of seed.
ii. State two functions of roots.
'c. (1) What is dispersal of seeds?
(11) State two characteristics of seeds dispersed by wind.
3. a. Apiece of stone has a mass of 360g. When it is put into water in a glass,
the level of water rises from 60.0cm to 90.0cm. Calculate the density of
(3r
(5
the stone.
b. i. List three benefits of vegetables to humans.
ii. Give two reasons why soil air is important.
c. 1. Define the term soil profile.
ii. State two ways in which soil profile is important in crop production

Heat is the amount of heat required to change the temperature of 1 gram of a substance by 1°c, and it is related to the chemical composition of the substance.

Which of the following is most important in making the typical seed more resistant to adverse conditions than the typical spore? a) a different type of sporopollenin b) an internal reservoir of liquid water c) integument(s) d) ability to be dispersed e) waxy cuticle

For your initial isolation of the bacterium, you simply needed to grow enough of it that you could identify some of its more general features. thus, you used a complex nutrient agar that would allow for the growth of almost any bacterial species. different bacterial species often have very specific requirements for life. this is a fact that you can utilize when you are trying to identify the bacterium to the species level. growth conditions that will permit the growth of one species but not another may allow you to select which one you would like to culture. you can utilize different selective/differential media that allow for the growth of only one type of bacteria (e.g., either gram positive or gram negative). culturing media such as phenylethyl alcohol or sodium chloride agar will be selective/differential for gram-positive bacteria. you may also want to show that it is different from other bacteria that may be present, so you could use a selective/differential agar. selective/differential media such as blood agar or phenol red sugar broths allow for the determination of whether a bacterial cell can grow and utilize specific ingredients included in the medium and turn the agar a distinct color. sheep's blood agar utilizes red blood cells to differentiate which bacterial species may have hemolytic properties.selective or differential? 1. an agar that uses a high salt concentration to limit the growth of one type of bacteria over another would be considered selective/differential. 2. if an agar contains a dye or ph indicator in the presence of a sugar, it is generally considered selective/differential for those bacteria that may ferment the sugar over those that cannot. 3. an agar that uses the dye in crystal violet agar suppresses the growth of gram-positive bacteria. this agar would be considered selective/differential. 4. the selective/differential aspect of macconkey agar allows for the determination of which bacteria are lactose fermenters and which are not. 5. a blood agar plate contains sheep red blood cells and allows for the determination of hemolytic capabilities for all bacteria that grow on the agar. this would make this type of agar selective/differential. 6. emb agar uses lactose and two dyes that allow it to be selective/differential between the blue-black colonies of e. coli and the pinkish colonies of all other enteric bacteria. 7. bile salts in macconkey agar allow for the agar to be selective/differential for the growth of enteric gram-negative bacteria over gram-positive bacteria. 8. an agar that allows for the distinction of bacteria based on metabolism would be considered selective/differential.