Biology Unit 4.1 Study Guide
Plants:
1. Distinguish between the root system and the shoot system – structure and function.
Root System: duh – roots…take in vital minerals, nutrients and water for the plant
Shoot System: structures within the plant(above ground) that takes nutrients throughout plant
2. Explain:
a. Phototropism: plant moves toward light (positive response) – regulated by the hormone Auxin
b. Thigmotropism: plant moves toward/away from touch (positive response: toward, negative response:
away from or closure of plant)
c. Hydrotropism: plant moves toward water (positive response)
d. Gravitropism (Geotropism): plant moves with/against gravity (positive response: roots growing down
w/gravity, negative response: plant growing up against gravity)
3. What role does Auxin play in how plants respond to light?
Plant hormone that moves away from the sun, causing cells to elongate on the shady side of the plant…causing
the plant to bend toward the sun.
4. How do the root and shoot systems work together to allow reproduction to occur?
Root system takes in nutrients needed for reproduction and the shoot system brings the nutrients to the
reproductive organs.
5. Compare/Contrast Xylem and Phloem:
Xylem: takes water and other dissolved nutrients up to the plant from the roots.
Phloem: takes sugars and other vital nutrients from the leaf (where photosynthesis occurs) to the rest of the
plant.
6. Explain how the stomata (and guard cells) help maintain homeostasis in plants – changes in water pressure and
exchange of gasses (O2 & CO2).
Stomata: pore like opening on the underside of the leaf. Takes in CO2 and releases O2. This gas exchange is
regulated by a pair of guard cells on the sides of the stomata. The guard cells open/close the stomata in
response to the environment. (water pressure, humidity, etc.)
7. Explain the process of pollination in plants Reproduction. (Self-Pollination vs Cross-Pollination)
Self-Pollination: Pollen taken in by the stigma from the same plant that produces the style – pollen(animals:
sperm) then travels down the style to the ovary where it will be germinated (animals:fertilized) with the
ovule(animals: egg)
Cross-Pollination: Pollen taken in from a secondary plant to germinate
8. Identify the parts that make up the reproductive organs of a sexually reproducing plant
Anther
Stigma
Filament
Style
Petal
Ovary
Ovule
Sepal
9. Compare gymnosperms and angiosperms:
Gymnosperm: reproduction within a cone
Angiosperm: reproduction within a flower
10. Define sporophyte & gametophyte:
Alternation of Generations – life cycle in which a diploid sporophyte generation alternates with a haploid
gametophyte generation
11. Describe the 3 plant tissue types:
a) Transport/Vascular – moves material throughout plant (animals: circulatory system)
b) Dermal – outermost layer (animals: skin <integumentary system>
c) Ground – cells that make up the “filler” between dermal and vascular tissue
Animals:
There are more than one way to explain the following…so I am not giving these to you (but we did plenty of activities in
class that can assist you in answering these) 
12. How do the circulatory and respiratory systems work together to perform daily activities?
13. How do the digestive and muscular systems work together to perform daily activities?
14. How do the reproductive and muscular systems work together to perform bodily functions?
15. How do the immune and endocrine systems work together to protect the body?
16. How do the nervous system and respiratory system work together to maintain homeostasis?
17. Compare and contrast 2 plant and animal systems (structure and function):
Homeostasis:
18. Compare and contrast positive and negative feedback:
Positive: response to a stimulus results in an increase in stimulus, eliciting a greater response (viscous cycle)
Negative: response to a stimulus results in return to homeostasis (balance)
19. Explain how these work to maintain homeostasis (negative or positive & what does the process regulate?):
a) Osmoregulation – regulation of nutrients within the bodily fluids of an organism
b) Thermoregulation – regulation of body temperature
c) Given a diagram – identify trends and describe what is being regulated by the process
Can you analyze what is happening in this diagram (or a similar one) –
20. Explain a simple reflex arc when a stimulus causes pain (negative feedback loop):
Can you relate this simple diagram to an example of pain as the stimulus –