When studying biology and involves more memorizing facts about organisms and how they live because
Answer:
plant: This Elodea leaf cell exemplifies a typical plant cell. It has a nucleus, and a stiff cell wall which gives the cell its box-like shape. The numerous green chloroplasts allow the cell to make its own food (by photosynthesis).
The central vacuole takes up most of the volume of the cell. It is transparent, but you can see where it's pressing the chloroplasts up against the cell wall, especially at the ends of the cell.
Like animal cells, the cytoplasm of this plant cell is bordered by a cell membrane. The membrane is so thin and transparent that you can't see it, but it is pressed against the inside of the cell wall.
animal :This human cheek cell is a good example of a typical animal cell. It has a prominent nucleus and a flexible cell membrane which gives the cell its irregular, soft-looking shape.
Like most eukaryotic cells, this cell is very large compared to prokaryotic cells. For scale, notice the pair of dark blue bacteria cells sticking to the right edge of the cheek cell. The bacteria are only a fraction of the size of the nucleus, but their tiny size is typical for bacteria.
The correct answer is upwelling from equatorial to Polar Regions results in bringing oxygen from the epipelagic zone to deeper oceanic zones.
It is a process in which the wind mediated motion of nutrient-rich, dense, and cooler water is moved towards the surface substituting the nutrient depleted and warmer surface water. The epipelagic zone refers to the upper layer of the ocean, which is abundant in oxygen and gets the majority of the sunlight for the procedure of photosynthesis. The upwelling of water from the equatorial to the polar region brings oxygen.
Answer and Explanation:
The retina covers the internal phase of the eye. It characterizes by its complex interaction between many morphologically and functionally different cells, which are located in many layers. The principal processing mechanism in the retina is lateral interactions among cells, and the most common lateral processing is lateral inhibition.
Photoreceptors are those cells that receive the light and translate the luminous signal into an electrical signal. These are the cones and sticks.
The horizontal cells intervene in the lateral spatial interaction between photoreceptors.
Bipolar cells receive information from the photoreceptors and from the horizontal cells and transmit it to the most internal layers in the retina.
The retina is stratified into five layers. One of these is the external plexiform layer, a contact zone between photoreceptors, horizontal cells, bipolar cells, and other cells.
In the vertebrates´ retina, the lateral inhibition is produced for the first time in the external plexiform layer, through the horizontal cells. These cells connect to photoreceptors, other horizontal cells, and bipolar cells. The connection between horizontal cells might reduce or amplify the photoreceptor answer, and this last one is transmitted by the bipolar cells to the interior of the retina. In photoreceptors, there are two connections to horizontal cells, a direct connection, and an indirect one. The connection between photoreceptors, horizontal cells, and bipolar cells is known as lateral inhibition. By this inhibition, photoreceptors allow the contrasting perception in an image. Lateral inhibition allows discriminating one stimulus from other stimuli, by enhancing contrast and definition. The inhibitory modulation is produced by the inhibitor neurotransmitter GABA.The spacial extension of lateral inhibition changes according to the adaptation to light. Gap junction between horizontal cells and between photoreceptors and horizontal cells might vary with the amount of light.
Answer:
Proportion of the F2 male with red eyes and forked bristle will be 1/4
Explanation:
forked bristles are caused by an allele (Xf) that is X linked and recessive to an allele for normal bristles (X+).
Brown eyes are caused by an allele (b) that is autosomal and recessive to an allele for red eyes (b+)
A female fly that is homozygous for normal bristles and red eyes mates with a male fly that has forked bristles and brown eyes
X+X+b+b+ x Xfbb
the F1 gives 1/2X+Xf 1/2b+b
1/2X+Y 1/2b+b
intercross of F1
Proportion of the F2 male with red eyes and forked bristle will be
forked bristle= Xfy = 1/2 and for red eyes 2/4= 1/2 = 1/2x1/2 =1/4