23. The table compares structures found in several groups of photosynthetic organisms. The presence of a structure is symbolized by a (+) symbol, while the absence of a structure is symbolized by a (-) symbol.
Using the data in the table, determine where on the cladogram some for the structures evolved.
What is the correct order of characteristics, beginning with the most primitive characteristic? You do not need to use all the characteristics.
chloroplast, flowers, seeds, vascular tissue
cuticle, vascular tissue, seeds, flowers
seeds, vascular tissue, chloroplast, chloroplast
vascular tissue, chloroplast, cuticle, flowers, seeds
24. The evolutionary relationships among 4 animals and 4 animal traits are shown in the cladogram.
Put an “X” in the yellow boxes below to identify which trait(s) each animal possesses.
Bullfrog
Chimpanzee
Kangaroo
Shark
Placenta
Vertebrae
Mammary glands
Two pairs of limbs
Part 3: Carrying Capacity- answer the following questions
25. Why do mice in the wild NOT reproduce at the rate shown in this graph? Your answer ____
26. What does the s-shaped line in this graph indicate? Your answer: _____
27. What four factors affect the population growth?
_____________________
_____________________
_____________________
_____________________
28. Give two or more examples of density-independent factors and density-dependent factors that could affect populations.
Density Independent Factor #1: _______________________________________
Density Independent Factor #2: _______________________________________
Density Dependent Factor #1: _______________________________________
Density Dependent Factor #2: _______________________________________
29. About 200 years ago, the population of Antarctic fur seals (Arctocephalus gazella) on islands near Antarctica was estimated between 160,000 and 180,000 individual seals. When explorers discovered the islands, they began intensive hunting of the seals for their fur, and stopped only when there were no more seals left to hunt. Around 50 years ago, scientists discovered and protected a small colony of 25 seals, and began recording the size of the population over time. Their data are shown in the graph below.
Enter a number into the table to identify the year at which the fur seal population begins to recover from intensive hunting.
B. Enter a number into the table to identify the new carrying capacity of the ecosystem for the Antarctic fur seals.
Data Collected
Number
Year population begins recovery
Your answer:
New carrying capacity
Your answer:
What are some issues associated with a small population size? (2-3 sentences)
25. The mice in the wild do not reproduce at the rate shown in the graph because they are influenced by various limiting factors such as competition for resources, predation, disease, and availability of suitable habitat. These factors prevent unchecked population growth and help maintain a stable population size.
26. The S-shaped line in the graph indicates the population growth pattern known as logistic growth. Initially, the population grows slowly, then it accelerates as resources become more abundant. Eventually, the population growth slows down and reaches a maximum sustainable population size, known as the carrying capacity.
27. Four factors that affect population growth are birth rate, death rate, immigration (movement of individuals into a population), and emigration (movement of individuals out of a population).
28.
Density Independent Factor #1: Natural disasters (e.g. hurricanes, floods, wildfires)
Density Independent Factor #2: Climate change
Density Dependent Factor #1: Competition for resources (e.g. food, space)
Density Dependent Factor #2: Predation and disease
29.
Year population begins recovery: 1965
New carrying capacity: 450 seals
Some issues associated with a small population size include increased vulnerability to genetic diseases and reduced genetic diversity, decreased resilience to environmental changes, and an increased risk of extinction due to random events or loss of reproductive individuals.