ACT Science : Biology
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Example Question #51 : Biology
Hormones are biochemical messengers utilized by multicellular organisms to coordinate development and behaviors. Hormones are secreted by the endocrine system and are key components in signal cascades that result in various essential activities. Plants, like animals, depend on hormonal signals for physiological adaptation and development.
There are several hormones that are primarily involved with seed germination and sprout formation. Abscisic acid, in high concentrations, prevents seed germination. Auxins are compounds that positively influence cell enlargement, the formation of buds, and the development of roots. Cytokinins influence cell division and shoot formation. Gibberellins promote seed germination as well as flowering and growth post-germination.
Study 1
Several scientists soaked Zea mays (corn) seeds in solutions rich in certain plant hormones. They observed and recorded seed germination and development over a three week period. At the end of the three week period, they measured coleoptile (the protective extension of sprout) and radicle (the primary root) growth of the seeds and plotted them in a graph (Figure 1).
Figure 1
Study 2
Scientists exposed Zea mays (corn) seeds to several hormonal treatments and measured coleoptile growth over a 14-day period and recorded their observations in a line graph (Figure 2). The groups consisted of a control exposed to saline solution, a treatment group exposed to a 0.15 millimolar solution of abscisic acid, and a treatment group exposed to a solution that included 0.15 millimoles of abscisic acid and 0.20 millimoles of gibberellins.
Figure 2
In Study 1, which of the treatments seemed to have little effect on coleoptile or radicle growth and development?
Abscisic acid
Cytokinins
Auxins
Gibberellins
Gibberellins
The second paragraph of the passage states that gibberellins kick-start the germination process; however, they do not provide impetus for growth or development until the plant is old enough to flower or produce fruit. This evidence is supported by Figure 1. The gibberellins treatment of the figure is comparable and not statistically different from the control.
Example Question #51 : Act Science
Hormones are biochemical messengers utilized by multicellular organisms to coordinate development and behaviors. Hormones are secreted by the endocrine system and are key components in signal cascades that result in various essential activities. Plants, like animals, depend on hormonal signals for physiological adaptation and development.
There are several hormones that are primarily involved with seed germination and sprout formation. Abscisic acid, in high concentrations, prevents seed germination. Auxins are compounds that positively influence cell enlargement, the formation of buds, and the development of roots. Cytokinins influence cell division and shoot formation. Gibberellins promote seed germination as well as flowering and growth post-germination.
Study 1
Several scientists soaked Zea mays (corn) seeds in solutions rich in certain plant hormones. They observed and recorded seed germination and development over a three week period. At the end of the three week period, they measured coleoptile (the protective extension of sprout) and radicle (the primary root) growth of the seeds and plotted them in a graph (Figure 1).
Figure 1
Study 2
Scientists exposed Zea mays (corn) seeds to several hormonal treatments and measured coleoptile growth over a 14-day period and recorded their observations in a line graph (Figure 2). The groups consisted of a control exposed to saline solution, a treatment group exposed to a 0.15 millimolar solution of abscisic acid, and a treatment group exposed to a solution that included 0.15 millimoles of abscisic acid and 0.20 millimoles of gibberellins.
Figure 2
In Study 1, which of the treatments seemed to favor coleoptile growth and development over radicle formation?
Abscisic acid
Auxins
Gibberellins
Cytokinins
Cytokinins
The second paragraph of the passage states that cytokinins primarily influence shoot formation. This suggests that they should enhance coleoptile growth. Figure 1 shows that this is indeed the case. The coleoptile bar of the cytokinins treatment is greatly enhanced while the radicle bar is comparable to the control.
Example Question #53 : Biology
Hormones are biochemical messengers utilized by multicellular organisms to coordinate development and behaviors. Hormones are secreted by the endocrine system and are key components in signal cascades that result in various essential activities. Plants, like animals, depend on hormonal signals for physiological adaptation and development.
There are several hormones that are primarily involved with seed germination and sprout formation. Abscisic acid, in high concentrations, prevents seed germination. Auxins are compounds that positively influence cell enlargement, the formation of buds, and the development of roots. Cytokinins influence cell division and shoot formation. Gibberellins promote seed germination as well as flowering and growth post-germination.
Study 1
Several scientists soaked Zea mays (corn) seeds in solutions rich in certain plant hormones. They observed and recorded seed germination and development over a three week period. At the end of the three week period, they measured coleoptile (the protective extension of sprout) and radicle (the primary root) growth of the seeds and plotted them in a graph (Figure 1).
Figure 1
Study 2
Scientists exposed Zea mays (corn) seeds to several hormonal treatments and measured coleoptile growth over a 14-day period and recorded their observations in a line graph (Figure 2). The groups consisted of a control exposed to saline solution, a treatment group exposed to a 0.15 millimolar solution of abscisic acid, and a treatment group exposed to a solution that included 0.15 millimoles of abscisic acid and 0.20 millimoles of gibberellins.
Figure 2
In Study 1, which treatment had an inhibitive effect on both coleoptile and radicle growth?
Abscisic acid
Gibberellins
Cytokinins
Auxins
Abscisic acid
Figure 1 contains four treatment and one control. In order to find the treatment that has an inhibitive effect on plant growth, one must find the bars that are smaller in size than that of the control. Only the abscisic acid group has values less than the control group.
Example Question #54 : Biology
Hormones are biochemical messengers utilized by multicellular organisms to coordinate development and behaviors. Hormones are secreted by the endocrine system and are key components in signal cascades that result in various essential activities. Plants, like animals, depend on hormonal signals for physiological adaptation and development.
There are several hormones that are primarily involved with seed germination and sprout formation. Abscisic acid, in high concentrations, prevents seed germination. Auxins are compounds that positively influence cell enlargement, the formation of buds, and the development of roots. Cytokinins influence cell division and shoot formation. Gibberellins promote seed germination as well as flowering and growth post-germination.
Study 1
Several scientists soaked Zea mays (corn) seeds in solutions rich in certain plant hormones. They observed and recorded seed germination and development over a three week period. At the end of the three week period, they measured coleoptile (the protective extension of sprout) and radicle (the primary root) growth of the seeds and plotted them in a graph (Figure 1).
Figure 1
Study 2
Scientists exposed Zea mays (corn) seeds to several hormonal treatments and measured coleoptile growth over a 14-day period and recorded their observations in a line graph (Figure 2). The groups consisted of a control exposed to saline solution, a treatment group exposed to a 0.15 millimolar solution of abscisic acid, and a treatment group exposed to a solution that included 0.15 millimoles of abscisic acid and 0.20 millimoles of gibberellins.
Figure 2
In Study 2, what was the average length of the coleoptiles in the abscisic acid and gibberellins trial on the 5th day of the study?
0.10 cm
1.25 cm
1 cm
2 cm
1 cm
The abscisic acid and gibberellins trial is represented by the dark grey line in Figure 2. On the 5th day, the average coleoptile length was 1 cm.
Example Question #55 : Biology
In the diagram below, each point represents caloric intake and muscle mass increase for specific body types for various male participants in the study described just below:
The participants maintained specific caloric intakes (charted on the horizontal axis) which resulted in specific muscle mass increases (charted on the vertical axis).
Each participant was categorized according to body mass constitution at the start of the 40-week trial, which consisted of heavy resistance training over the course of those 40 weeks.
The body mass categories were described as such:
Type A: Long and slim limbs, narrow waist/torso, low fat storage, low muscle mass.
Type B: Medium bones, solid torso, low fat levels, narrow waist, moderate muscle mass.
Type C: High fat storage, wide waist/shoulders, large bone structure, moderate muscle mass.
Which of the the following is closest to the average muscle mass increase of the two individuals who had daily caloric intakes of 3700?
10.15 lbs
14.05 lbs
11.85 lbs
6.75 lbs
11.85 lbs
According to the chart, C9 and B7 had caloric intakes of 3700, and muscle mass increases of (about) 14 and 10 pounds respectively.
The average of 14 and 10 is 12. The closest choice to 12 is 11.85.
Example Question #51 : Biology
In the diagram below, each point represents caloric intake and muscle mass increase for specific body types for various male participants in the study described just below:
The participants maintained specific caloric intakes (charted on the horizontal axis) which resulted in specific muscle mass increases (charted on the vertical axis).
Each participant was categorized according to body mass constitution at the start of the 40-week trial, which consisted of heavy resistance training over the course of those 40 weeks.
The body mass categories were described as such:
Type A: Long and slim limbs, narrow waist/torso, low fat storage, low muscle mass.
Type B: Medium bones, solid torso, low fat levels, narrow waist, moderate muscle mass.
Type C: High fat storage, wide waist/shoulders, large bone structure, moderate muscle mass.
Of the following pairs, which two had about the same muscle mass increase, but radically different caloric intakes?
A10 and B10
C6 and B5
C2 and B3
A10 and C4
A10 and C4
A10 and C4 both had muscle mass increases of 8 lbs, but had daily caloric intakes of around 4000 and 2800 respectively.
Example Question #51 : Biology
In the diagram below, each point represents caloric intake and muscle mass increase for specific body types for various male participants in the study described just below:
The participants maintained specific caloric intakes (charted on the horizontal axis) which resulted in specific muscle mass increases (charted on the vertical axis).
Each participant was categorized according to body mass constitution at the start of the 40-week trial, which consisted of heavy resistance training over the course of those 40 weeks.
The body mass categories were described as such:
Type A: Long and slim limbs, narrow waist/torso, low fat storage, low muscle mass.
Type B: Medium bones, solid torso, low fat levels, narrow waist, moderate muscle mass.
Type C: High fat storage, wide waist/shoulders, large bone structure, moderate muscle mass.
Which of the following claims can be made about heavy resistance training as a factor of muscle mass increase based on the results of the study?
The results of low heavy resistance training can be mitigated by high caloric intake.
None: Muscle mass increase is most readily determined by caloric intake and body type.
The effect of heavy resistance training is highly dependant on the body type of the particular participant.
None: there were no measures taken to isolate heavy resistance training as a seperate factor of determining muscle mass.
None: there were no measures taken to isolate heavy resistance training as a seperate factor of determining muscle mass.
None: there were no measures taken to isolate heavy resistance training as a seperate factor of determining muscle mass.
The only factors varied are caloric intake and body type. No variation in resistance training is specified.
Example Question #58 : Biology
In the diagram below, each point represents caloric intake and muscle mass increase for specific body types for various male participants in the study described just below:
The participants maintained specific caloric intakes (charted on the horizontal axis) which resulted in specific muscle mass increases (charted on the vertical axis).
Each participant was categorized according to body mass constitution at the start of the 40-week trial, which consisted of heavy resistance training over the course of those 40 weeks.
The body mass categories were described as such:
Type A: Long and slim limbs, narrow waist/torso, low fat storage, low muscle mass.
Type B: Medium bones, solid torso, low fat levels, narrow waist, moderate muscle mass.
Type C: High fat storage, wide waist/shoulders, large bone structure, moderate muscle mass.
From the results of the study, which can be determined as a leading detriment to muscle mass increase?
Low muscle mass.
A combination of moderate muscle mass and low fat levels.
Medium bones.
High fat storage.
Low muscle mass.
Type A showed the lowest muscle mass increase, and the only characteristic that it had seperate from the other two types is low muscle mass.
Example Question #59 : Biology
In the diagram below, each point represents caloric intake and muscle mass increase for specific body types for various male participants in the study described just below:
The participants maintained specific caloric intakes (charted on the horizontal axis) which resulted in specific muscle mass increases (charted on the vertical axis).
Each participant was categorized according to body mass constitution at the start of the 40-week trial, which consisted of heavy resistance training over the course of those 40 weeks.
The body mass categories were described as such:
Type A: Long and slim limbs, narrow waist/torso, low fat storage, low muscle mass.
Type B: Medium bones, solid torso, low fat levels, narrow waist, moderate muscle mass.
Type C: High fat storage, wide waist/shoulders, large bone structure, moderate muscle mass.
What conclusion can be made about type C muscle mass increase?
It is independant of resistance training.
There is eventually diminishing returns from increased caloric intake.
It is independant of caloric intake.
It is low at low levels of caloric intake, but, high at high levels.
There is eventually diminishing returns from increased caloric intake.
Arround just before 3300 daily calories, type C muscle mass increase starts to diplay diminished returns.
Example Question #60 : Biology
In the diagram below, each point represents caloric intake and muscle mass increase for specific body types for various male participants in the study described just below:
The participants maintained specific caloric intakes (charted on the horizontal axis) which resulted in specific muscle mass increases (charted on the vertical axis).
Each participant was categorized according to body mass constitution at the start of the 40-week trial, which consisted of heavy resistance training over the course of those 40 weeks.
The body mass categories were described as such:
Type A: Long and slim limbs, narrow waist/torso, low fat storage, low muscle mass.
Type B: Medium bones, solid torso, low fat levels, narrow waist, moderate muscle mass.
Type C: High fat storage, wide waist/shoulders, large bone structure, moderate muscle mass.
What conclusion can be made about type A muscle mass?
It is independant from caloric intake.
It is independant from resistance training.
As daily caloric intake increases, muscle mass increase for type A begins to display diminished returns.
It is low at low levels of caloric intake, but increases rapdily at high levels.
It is low at low levels of caloric intake, but increases rapdily at high levels.
Muscle mass increase is low in type A until around 3000 daily calories where it begins to increase at a more rapid rate.
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