Lecture 1a Flashcards
What were Robert Hooke’s achievements?
Built a microscope, discovered microorganisms, and coined the term ‘cell’. This was the first breakthrough in understanding why/how we exist.
What did Robert Hooke look at under the microscope?
Cork, a layer in tree bark. He saw “microscopic rooms” he called cells.
What did Hooke not know?
That all living things were made of cells.
Who discovered that all living things were made of cells?
Schleiden (worked with plants) and Schwann (worked with animals).
What did Schleiden also uncover about plants?
Plants start off as single cells that then divide and keep dividing to become multicellular organisms.
What is inheritance?
Instructions in cells being passed down to offspring.
What is genetics?
The study of life’s instructions and how they are altered by mutation and passed down to offspring.
What were the early theories of inheritance? Were they correct?
Theory of Pangenesis, spermists, ovists, and blending theory of inheritance. All were incorrect.
What is the theory of pangenesis?
Hippocrates said that all parts of the body make seeds that are collected and transmitted to offspring. Seeds from the arms will make arms and so on.
What did the spermists believe?
A tiny human called a homunculus is in a sperm, making the father entirely responsible for inheritance. Any resemblance to mom comes from womb influences.
What did the ovists believe?
Mom’s egg is entirely responsible for inheritance. The sperm only stimulates the egg to develop.
What is the blending theory of inheritance?
Stated that the factors that dictate inheritance blend together from generation to generation. This was a very vague idea.
Who was deemed the father of genetics?
Mendel
What can Mendel’s success be attributed to?
His boyhood experience in grafting trees and his university experience in physics and natural history.
What is a hermaphrodite?
A plant or animal that has both male and female reproductive organs.
Why did Mendel choose Pea Plants as his experimental organism?
1) Garden peas could be purchased in many varieties with distinct characteristics.
2) The structure of the garden pea allowed for easy crosses where the parents could be controlled.
What is the anther of the pea plant?
It contains the pollen grains, where the male gametes are produced.
How does pollination and fertilization work in flowering plants?
A pollen tube will grow out of the plant, where pollen grain can enter and travel to the egg.
What does the endosperm nucleus do?
Provides food for the developing embryo.
What types of crosses did Mendel carry out?
Self-fertilization and cross-fertilization.
What is self-fertilization?
When the pollen and egg are derived from the same plant.
What is cross-fertilization?
When the pollen and egg are derived from different plants.
What is hybridization?
Mating between two individuals that have different characteristics.
What are hybrids?
The offspring that results from mating between two individuals with different characteristics.
