Unit 5 - Biology Flashcards
(34 cards)
1
Q
Cell Theory
A
- All living things are made up of +1 cells
- Cells are basic unit of life
- Cells come from pre-existing cells
2
Q
Prokaryote
A
- Cell doesn’t contain nucleus or membrane-bound organelles.
- Bacteria and archaea
- Tens to thousands of times smaller than eukaryotes
3
Q
Eukaryote
A
- Cell that contains nucleus and other organelles surrounded by thin membrane
- Protists, fungi, animals, and plants
4
Q
Organelle
A
Cell structure that performs specific function for cell
5
Q
Cytoplasm
A
- Suspends all organelles in cell and moves them around
- Mostly water, other substances cell stores until needed
- Chemical reactions take place, changing it from jelly-like to liquid
6
Q
Cell Membrane
A
- Flexible double-layered organelle surrounding cell
- Allows some substances (ex: water, oxygen) to enter, keeps others (ex: proteins) out
- “Semi-permeable membrane”
7
Q
Nucleus
A
- Roughly spherical structure containing genetic information controlling cell activities
- Stores info in chromosomes containing deoxyribonucleic acid, or coded instructions
- DNA copied when cell divides so new cell has complete DNA
8
Q
Mitochondria (s: mitochondrion)
A
- Cells store energy as glucose.
- Mitochondria contains enzymes converting stored energy for use (known as cellular respiration - requires oxygen)
9
Q
Active vs. Passive Cells
A
Active cells (muscles) have more mitochondria than others (fat-storage - may have 1-2 only) as they need faster cellular respiration
10
Q
Endoplasmic reticulum
A
- 3D branching tubes and pockets extending through cytoplasm and from nucleus to cell membrane
- Fluid-filled tubes transport material through cell
11
Q
Golgi bodies
A
- Collect materials to be removed from cell
- Make and secrete mucus.
- Cells that secrete lot of mucus (ex: cells lining intestine) have many Golgi bodies.
12
Q
Vacuole
A
- Single layer of membrane enclosing fluid in sac.
- Containing substances, removing unwanted substances from cell, maintaining internal fluid pressure (turgor) within the cell.
13
Q
Animal vs. Plant Vacuoles
A
- Animal cells have small vacuoles not visible.
- Mature plant cells have one central vacuole visible under microscope.
14
Q
Plant: Cell Wall
A
- Outside cell membrane.
- Rigid but porous structure made of cellulose.
- Holds long after plant died.
15
Q
Large Vacuole
A
- Vacuole takes most space inside cell.
- When full of water, turgor pressure keeps cells plump, keeping plant’s stems firm.
- If water level drops, vacuoles lose turgor pressure and cells become soft
16
Q
Chloroplast
A
- Plant cells exposed to light have chloroplasts
- Contain chlorophyll, absorbing light energy used in photosynthesis
17
Q
Asexual Reproduction
A
- Producing offspring from one parent cell
- Offspring is genetically identical to parent, receiving complete set of genetics
18
Q
Sexual Reproduction Details
A
- Parent cells typically have half of DNA in regular cell
- Half-cells known as “gametes”
19
Q
Cell Division
A
- Allows organisms to reproduce, grow and repair damage
- Used by all cells to reproduce
20
Q
Sexual Reproduction Process
A
- Producing offspring by fusion of two gametes
- Offspring has genetics from each parent
21
Q
Meiosis
A
Additional cell division process production of gametes entails
22
Q
Diffusion
A
- Transport for moving chemicals into and out of cell from area of higher concentration to that of lower concentration
- Chemicals enter cell across membrane to cell
23
Q
Osmosis
A
Movement of fluid across membrane toward area of high concentration
24
Q
Reason for Size of Cells
A
- Chemicals must be available to all parts of cell, in right amount of water
- Waste products must diffuse out of cell quickly
- Chemicals and water cannot move through large cells fast enough.
25
Reproduction
Transfer of genetic information from parent to offspring.
26
Cell cycle
- Three stages cell passes through
- Embryonic cells divide rapidly, some cells taking 30h for cycle
- Specialized cells (ex: adult nerve cells) never divide
27
A: Interphase
- Cell in interphase for 90% of time, growing and fulfilling normal function
- Chromatin makes identical DNA, doubling self
- Centrosomes + other organelles make identical copy as well
28
Chromatin
Long and thin strands of DNA filling nucleus
29
Mitosis A: Prophase (1st stage)
- Chromatin twists and becomes thick and short
- Identical sister chromatid attach together to make chromosome
- Nucleolus and Nuclear Membrane disappear
- Centrosomes travel to poles
30
Mitosis B: Metaphase
- Chromosomes line on equatorial plane (middle line)
- Centrosomes arrive at poles of cell and produce spindle fibers
- Spindle fibers attach to two sister chromatids in chromosome
31
Mitosis C: Anaphase
- Spindle fibers pull one sister chromatid of each chromosome to each of poles
- Ensures each cell gets copy of each chromosome
32
Mitosis D: Telophase
- Cells begin to separate
- Nucleolus and Nuclear Membrane reappear
- Chromosomes begin to unravel back into chromatin inside nuclear membrane
33
Cytokinesis
- Cytoplasm and organelles evenly distributed between two cells
- Cell divides to form two new cells
34
Body Parts by Size
Systems > Organ > Tissue > Cell
