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(Chemical Reactions Part 1 : Matter and Energy in Chemical Reactions)
Why is the law of conservation of matter important in chemical reactions?

- states that matter is neither lost nor gained in traditional chemical reactions, it simply changes form
- thus, if we have a certain number of atoms of an element on the left side of the equation, we have to have the same number on the right side
- this implies that mass is also conserved during a chemical reaction.

1

(Chemical Reactions Part 1 : Matter and Energy in Chemical Reactions)
What happens during a chemical reaction?

- process in which atoms are rearranged to form new substances
- reactants : the starting materials for a chemical reaction
- products : the materials produced during a chemical reaction

2

(Chemical Reactions Part 1 : Matter and Energy in Chemical Reactions)
Why is the law of conservation of energy important in chemical reactions?

- states that atoms are neither created nor destroyed in a chemical reaction - they are just rearranged
- every atom present before a reaction must be present after the reaction - even though the groupings of atoms are different (the law of mass conservation states that a chemical equation must be balanced; meaning that each atom shown in the equation must appear on both sides the same number of times)
- endothermic : reactants have less energy than products, energy is absorbed
- exothermic : reactants have more energy than products, energy is released

3

(Chemical Reactions Part 1 : Matter and Energy in Chemical Reactions)
matter

- anything that has mass and takes up space, anything made of atoms
- examples : chicken, tree, micro organisms

4

(Chemical Reactions Part 1 : Matter and Energy in Chemical Reactions)
energy

- the ability to do work or cause change, can move through matter, has no substance
- examples : light

5

(Chemical Reactions Part 1 : Matter and Energy in Chemical Reactions)
What is the law of conservation of energy?
(A) Atoms cannot be created or destroyed during chemical reactions.
(B) Energy cannot be created or destroyed during chemical reactions.
(C) Energy can be converted from one form to another, but cannot be transferred.
(D) Atoms can be converted into energy, and energy can be converted into atoms.

ANSWER
(B) Energy cannot be created or destroyed during chemical reactions.

6

(Chemical Reactions Part 1 : Matter and Energy in Chemical Reactions)
When baking soda reacts with vinegar, it forms water, carbon dioxide, and sodium acetate. Which statement about this reaction is correct?
(A) The reactants are baking soda and vinegar; the products are water, carbon dioxide, and sodium acetate.
(B) The reactants are water, carbon dioxide, and sodium acetate; the products are baking soda and vinegar.
(C) The reactants are carbon atoms and sodium atoms; the products are hydrogen atoms and oxygen atoms.
(D) The reactants are water and vinegar; the products are baking soda, carbon dioxide, and sodium acetate.

ANSWER
(A) The reactants are baking soda and vinegar; the products are water, carbon dioxide, and sodium acetate.

7

(Chemical Reactions Part 1 : Matter and Energy in Chemical Reactions)
A chemical reaction releases energy. What MUST be true about the reaction?
(A) It involves organic substances being converted into inorganic substances.
(B) The products have more energy than the reactants.
(C) It involves plans using light energy.
(D) The reactants have more energy than the products.

ANSWER
(D) The reactants have more energy than the products.

8

(Chemical Reactions Part 1 : Matter and Energy in Chemical Reactions)
Which of these reactions absorbs energy from the environment?
(A) wood burning
(B) dynamite exploding
(C) a chemical cold pack
(D) a glow stick

ANSWER
(C) a chemical cold pack

9

(Chemical Reactions Part 2 : Reaction Rates)
Explain how the following factors affect the reaction rate of chemical reactions :
(A) concentration of reactants
(B) temperature
(C) the addition of a catalyst

(A) concentration of reactants :
- if there is a large concentration of reactants, the reaction will be fast, if there is not a lot of reactants present, the reaction will be slow.
- more molecules = more collisions = faster reaction
(B) temperature :
- higher temperature = more collisions = faster reaction
(C) the addition of a catalyst : lowers the activation energy needed which makes the reaction faster

10

(Chemical Reactions Part 2 : Reaction Rates)
What is activation energy? How do catalysts affect activation energy?

- the amount of energy required to activate atoms or molecules to a state in which they can undergo a chemical reaction
- reduces the amount of activation energy needed

11

(Chemical Reactions Part 2 : Reaction Rates)
How do enzymes speed up chemical reactions in cells?

- they are large, complex proteins in cells of living organisms that act as a catalyst
- it binds the reactants of a reaction and releases the products of the reaction
- they are not altered or destroying in the reactions they catalyze - making them available for the same reaction over and over

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(Chemical Reactions Part 2 : Reaction Rates)
catalyst

- a substance that speeds up a chemical reaction without being used up during the reaction

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(Chemical Reactions Part 2 : Reaction Rates)
enzyme

- a protein that acts as a catalyst for cellular processes

14

(Chemical Reactions Part 2 : Reaction Rates)
A student adds an effervescent antacid tablet to a cup of water. What could the student do to make the tablet react faster
(A) Increase the amount water in the cup.
(B) Increase the temperature of the water in the cup.
(C) Put the water into a larger cup.
(D) Put the tablet in the refrigerator before adding it to the water.

ANSWER
(B) Increase the temperature of the water in the cup.

15

(Chemical Reactions Part 2 : Reaction Rates)
A car's catalytic converter uses platinum as a catalyst to speed up the reaction between exhaust gases and oxygen. This helps produce less toxic exhaust emission. What happens to the amount of platinum in the catalytic converter over time?
(A) It decreases as the platinum is used up in reactions.
(B) It increases as the reactions deposit platinum.
(C) It stays the same as platinum speeds up the reactions.
(D) It depends on the type of gasoline that's burned.

ANSWER
(C) It stays the same as platinum speeds up the reaction.

16

(Chemical Reactions Part 2 : Reaction Rates)
Which of the following actions would decrease the rate of a chemical reaction?
(A) increasing the temperature of the reactants
(B) adding more reactant molecules
(C) introducing a catalyst to the reaction
(D) separating the reactants from each other

ANSWER
(D) separating the reactants from each other

17

(Cells Part 1 : Cell Types)
Describe the characteristics of living things (organisms).

- use energy, develop and grow, maintain themselves, can reproduce, are part of evolving populations

18

(Cells Part 1 : Cell Types)
How do plant cells differ from animal cells?

- plant cells : cell membranes, rigid cell wall, chloroplasts, large central vacuoles
- animal cells : cell membrane, no wall, no chloroplasts, no central vacuoles

19

(Cells Part 1 : Cell Types)
One difference between prokaryotic and eukaryotic cells is :
(A) Prokaryotic cells have a nucleus, whereas eukaryotic cells do not
(B) Eukaryotic cells have existed on Earth far longer than prokaryotic cells
(C) The DNA of eukaryotic cells is found in linear chromosomes, whereas DNA of prokaryotic cells is found in a single circular chromosome
(D) Eukaryotic cells are generally smaller than prokaryotic cells

ANSWER
(C) The DNA of eukaryotic cells is found in linear chromosomes, whereas DNA of prokaryotic cells is found in a single circular chromosome.

20

(Cells Part 2 : Mitosis)
What is the end result of mitosis?

- cytokinesis, the division of cytoplasm to yield two separate identical daughter cells (diploid)

21

(Cells Part 2 : Mitosis)
What is the purpose of mitosis?

- body cell division
- type of cell division that results in two daughter cells each the same as the parent nucleus, typical of ordinary tissue growth
- used for growth and repair involving body cells (somantic cells)

22

(Cells Part 2 : Mitosis)
Which of these statements is NOT correct about mitosis?
(A) Each new daughter cell is identical to the parent cell
(B) Each new daughter cell contains only one copy of each chromosome (haploid)
(C) Mitosis occurs in somatic (body) cells
(D) Each new daughter cell contains two copies of every chromosome (homologous pairs)

ANSWER
(B) Each new daughter cell contains only one copy of each chromosome (haploid)

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(Cells Part 2 : Mitosis)
In what stage of mitosis do sister chromatids separate?
(A) Prophase
(B) Metaphase
(C) Anaphase
(D) Telophase

ANSWER
(C) Anaphase

24

(Cells Part 2 : Mitosis)
In mitosis, what happens during metaphase?
(A) The cell divides up its cytoplasm and splits into two daughter cells
(B) Chromosomes line up along the center of the cell
(C) Nuclear membrane breaks down, chromosomes condense and microtubules form
(D) Sister chromatids separate

ANSWER
(B) Chromosomes line up along the center of the cell

25

(Cells Part 3 : Meiosis)
What is the end result of meiosis?

- cytokinesis occurs, producing four haploid daughter cells

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(Cells Part 3 : Meiosis)
What is the function of meiosis?

- sex cell division
- cell division that produces reproductive cells in sexually reproducing organisms
- number of chromosomes are reduced by half through the separation of chromosomes making a diploid cell

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(Cells Part 3 : Meiosis)
What is a gamete?

- a mature haploid male or female germ cell that is able to unite with another of the opposite sex in sexual reproduction to form a zygote.

28

(Cells Part 3 : Meiosis)
Which of these statements is NOT correct about meiosis?
(A) Meiosis occurs in reproductive cells (produces gametes)
(B) Each new daughter cell is NOT identical to the parent cell
(C) Meiosis results in two identical daughter cells
(D) Each new daughter cell contains only ONE copy of each chromosome (haploid)

ANSWER
(C) Meiosis results in two identical daughter cells

29

(Cells Part 3 : Meiosis)
In meiosis, what happens during anaphase I?
(A) Homologous chromosomes separate
(B) The cell divides up its cytoplasm and splits into two new daughter cells
(C) Sister chromatids separate
(D) New nuclear membranes are formed and chromosomes de condense

ANSWER
(A) Homologous chromosomes separate