Leader: Kirsten Karkow
Course: Biol 211 - Wilsey
Date: 2/22/2012
Worksheet 14
Supplemental Instruction
Iowa State University
Finishing Development of Vertebrates …
6. Amniotes – animals that create an amniotic egg – amnion, yolk sac, allantois, albumin,
shell.
6a. Reptilia
o Includes turtles, lizards & snakes, crocodilians, dinosaurs, and birds.
 Archaeopteryx – dinosaur fossil, original bird.
o Have scales of keratin to prevent desiccation. (Feathers = modified scales).
o Breathe via lungs.
o Are generally ectotherms. (Major exception!)
6ai. Birds
 Are endotherms. (Feathers provide warmth)
 “Honeycomb” bones, reduced organs, and wings all help with flight.
 Benefits of flight:
 More food options (insects)
 Quick escape from predators
 Migration
7. Mammalia
o
o
o
o
o
o
Named for mammary glands (produce milk).
Are endotherms.
Have hair for warmth.
Have a 4-chambered heart.
Most are viviparous – give birth to live young.
Have specialized teeth for their diet.
7a. Monotremes
o Classified as mammals that lay eggs.
o Includes echidnas (spiny anteaters) and platypuses.
7b. Marsupials
o Classified as mammals that give birth to partially developed young.
o Named for their marsupium (pouch).
7c. Eutherians
o Classified as mammals that complete embryonic development in the uterus.
o Embryo supported through a placenta.
Supplemental Instruction
1060 Hixson-Lied Student Success Center  294-6624  www.si.iastate.edu
Primate Characteristics:
1.
2.
3.
4.
5.
6.
7.
8.
Early primates lived in trees (arboreal).
Have limber shoulder joints for swinging.
Have dexterous hands with opposable thumbs.
Have improved hand-eye coordination.
Have nails instead of claws.
Have eyes close together → binocular vision → depth perception.
Nurture their offspring, providing parental care for a long time.
Usually have single births.
Human Characteristics: all of those above PLUS
1. Stand up-right (bipedal), thus have big pelvises.
2. Larger brain compared to body.
Fill in the blank:
Monkeys and apes are not the same thing. Humans and apes are most closely related. They
share a common ancestor.
Chimpanzees (bonobos) and humans share 99% of their DNA.
Modern-day humans (Homo sapiens) are hypothesized to have originated from Africa. The
evidence for this is found in mitochondrial DNA and on the Y chromosome.
Starting Cell Cycle …
Define the following terms:
Term
Cell Cycle
Interphase
Mitosis
Cytokinesis
Genome
Gene
*Chromatin
*Chromatid
*Chromosome
Somatic Cells
Gametes
Definition
From the creation of a cell to that cell’s division (division to division). Includes
interphase, mitosis, and cytokinesis.
Phase between divisions. Includes cell growth and replication of DNA.
Division of the nucleus. Exact opposite of karyogamy.
Division of the cytoplasm. Exact opposite of plasmogamy.
All of the genetic information in a cell.
A specific coding region of DNA (→ RNA → protein).
Loose DNA (+ associated proteins) present within not-currently-dividing cells.
Condensed/coiled version of chromatin present during mitosis. Refers to ONE
DNA molecule.
Whole condensed version of chromatin. May be made of ONE or TWO DNA
molecules, depending upon whether the duplicated strands have split yet.
Asexual cells (all except the reproductive cells). 2N. Formed by mitosis.
Reproductive cells – sperm and eggs. N. Formed by meiosis.
*NEED TO UNDERSTAND THE DIFFERENCES BETWEEN THESE! VERY IMPORTANT!