Cellkärnan Flashcards
Which 4 parts make up the eukaryote cell nucleus?
Nuclear envelope. Nucleoplasm. Nucleolus. Chromatin.
Describe the parts of the nuclear envelope.
There’s two membranes, an outer nuclear membrane and a inner membrane that’s covered by the nuclear lamina. A reticular fibrous network. Transport through the nuclear envelope is managed by pores in the membrane.
Describe the nucleolus.
The nucleolus is the primary seat of ribosome-production in the cell. It comprises of the Fibrillar center (FC), The dense Fibrillar component (DFC), the granular component (GC).
What is the nucleoplasm and it’s functions?
Everything within the nucleous that’s not chromatin or the nucleolus. It’s a gel-like substance that keeps the nucleus and it’s contents structurally stabile.
What is chromatin? And it’s main function?
It is DNA wrapped around histones. To effectively package DNA.
What is the difference between Heterochromatin and Euchromatin? What conclusion can you draw from a cell with a lot of Euchromatin?
Heterochromatin that’s packed densely. Where as Euchromatin is chromatin spred out. When the chromatin is spread out it’s often a sign of activity since to be transcribed or translated the DNA needs to be readable, therefore spred out.
What is a karyosome?
It’s a gathering of chromatin. Occurs when a cell is not undergoing meiosis?(only meiosis, not mitosis?)
What are the two types of Heterochromatin called?
Facultative and constitutive.
Which is the most basic chromatin-unit?
Nucleosome
What is the difference of a haploid and diploid cell?
The Diploid cell has 46 chromosomes in homologue pairs while the haploid only has 23 single chromosomes. (Sperm- and egg-cells).