Understanding Fossil Evidence - AP Biology

Lamarck incorrectly believed that parents could pass on traits that they had acquired to their offspring. He believed that the changes made during a lifetime, such as increased muscle mass, would be passed on to offspring. This is not true since acquired traits, except on very few rare occasions, do not affect the DNA. For example, if two parents have small muscles, but then take steroids and become bodybuilders, their offspring will still inherit the small muscle genes, since only the muscles, not the DNA is affected by bodybuilding.

When a thermal neutron collides with a nitrogen atom in the atmosphere, it causes a proton to fly off from the atom, reducing the atom from nitrogen to carbon while keeping the same number of neutrons, 14. Because the amount of matter in the universe is believed to be constant, we can measure the amount of carbon-14 left in a dead specimen to determine its age within approximately 50,000 years.

Coprolites are fossilized fecal matter from an animal. By studying their contents, biologists can gather information on what the animal ate, and what species were there to be eaten by the animal.

Carbon-14 dating is used to date organic material within an approximately 50,000 year time period, due to the relatively short half life of the carbon-14 isotope. Other isotopes are used to date the rocks surrounding dinosaur fossils, such as in the uranium-lead method or the potassium-argon method.

The key to answering this question is organic material. Once an organism dies, it ceases to participate in carbon exchanges with the atmosphere. What carbon is left in the organism then decreases at a stable rate which allows scientists to reliable date the era that the organism died in.

It is believed that sponges were the first animals to utilize multicellularity. Sponges only have a few cell types, including: choanocytes, porocytes, and pinacocytes. Choanocytes have flagella that beat continuously to move water, and microvilli, which are specialized for absorbing nutrients. Porocytes are tubular cells that form the pores of sponges. Pinacocytes produce collagen and provide structural support to the sponge. Although algae likely developed multicellularity early on, they are not animals. Arthropods and mammals are both multicellular and animals, but evolved after sponges.

Lamarck incorrectly believed that parents could pass on traits that they had acquired to their offspring. He believed that the changes made during a lifetime, such as increased muscle mass, would be passed on to offspring. This is not true since acquired traits, except on very few rare occasions, do not affect the DNA. For example, if two parents have small muscles, but then take steroids and become bodybuilders, their offspring will still inherit the small muscle genes, since only the muscles, not the DNA is affected by bodybuilding.

When a thermal neutron collides with a nitrogen atom in the atmosphere, it causes a proton to fly off from the atom, reducing the atom from nitrogen to carbon while keeping the same number of neutrons, 14. Because the amount of matter in the universe is believed to be constant, we can measure the amount of carbon-14 left in a dead specimen to determine its age within approximately 50,000 years.

Coprolites are fossilized fecal matter from an animal. By studying their contents, biologists can gather information on what the animal ate, and what species were there to be eaten by the animal.

Carbon-14 dating is used to date organic material within an approximately 50,000 year time period, due to the relatively short half life of the carbon-14 isotope. Other isotopes are used to date the rocks surrounding dinosaur fossils, such as in the uranium-lead method or the potassium-argon method.

The key to answering this question is organic material. Once an organism dies, it ceases to participate in carbon exchanges with the atmosphere. What carbon is left in the organism then decreases at a stable rate which allows scientists to reliable date the era that the organism died in.

It is believed that sponges were the first animals to utilize multicellularity. Sponges only have a few cell types, including: choanocytes, porocytes, and pinacocytes. Choanocytes have flagella that beat continuously to move water, and microvilli, which are specialized for absorbing nutrients. Porocytes are tubular cells that form the pores of sponges. Pinacocytes produce collagen and provide structural support to the sponge. Although algae likely developed multicellularity early on, they are not animals. Arthropods and mammals are both multicellular and animals, but evolved after sponges.

Lamarck incorrectly believed that parents could pass on traits that they had acquired to their offspring. He believed that the changes made during a lifetime, such as increased muscle mass, would be passed on to offspring. This is not true since acquired traits, except on very few rare occasions, do not affect the DNA. For example, if two parents have small muscles, but then take steroids and become bodybuilders, their offspring will still inherit the small muscle genes, since only the muscles, not the DNA is affected by bodybuilding.

When a thermal neutron collides with a nitrogen atom in the atmosphere, it causes a proton to fly off from the atom, reducing the atom from nitrogen to carbon while keeping the same number of neutrons, 14. Because the amount of matter in the universe is believed to be constant, we can measure the amount of carbon-14 left in a dead specimen to determine its age within approximately 50,000 years.

Coprolites are fossilized fecal matter from an animal. By studying their contents, biologists can gather information on what the animal ate, and what species were there to be eaten by the animal.

Carbon-14 dating is used to date organic material within an approximately 50,000 year time period, due to the relatively short half life of the carbon-14 isotope. Other isotopes are used to date the rocks surrounding dinosaur fossils, such as in the uranium-lead method or the potassium-argon method.

The key to answering this question is organic material. Once an organism dies, it ceases to participate in carbon exchanges with the atmosphere. What carbon is left in the organism then decreases at a stable rate which allows scientists to reliable date the era that the organism died in.

It is believed that sponges were the first animals to utilize multicellularity. Sponges only have a few cell types, including: choanocytes, porocytes, and pinacocytes. Choanocytes have flagella that beat continuously to move water, and microvilli, which are specialized for absorbing nutrients. Porocytes are tubular cells that form the pores of sponges. Pinacocytes produce collagen and provide structural support to the sponge. Although algae likely developed multicellularity early on, they are not animals. Arthropods and mammals are both multicellular and animals, but evolved after sponges.

Lamarck incorrectly believed that parents could pass on traits that they had acquired to their offspring. He believed that the changes made during a lifetime, such as increased muscle mass, would be passed on to offspring. This is not true since acquired traits, except on very few rare occasions, do not affect the DNA. For example, if two parents have small muscles, but then take steroids and become bodybuilders, their offspring will still inherit the small muscle genes, since only the muscles, not the DNA is affected by bodybuilding.